Filed Pursuant to Rule 424(b)(4)
Registration No. 333-274780

PROSPECTUS

20,325,500 Ordinary Shares

(Including Ordinary Shares in the Form of American Depositary Shares)

€10.9864 per Ordinary Share

$11.60 per American Depositary Share

We are offering an aggregate of 20,325,500 ordinary shares in a global offering.

We are offering 18,699,460 ordinary shares in the form of American Depositary Shares, or ADSs, in the United States, referred to herein as the U.S. offering. Each ADS represents the right to receive one ordinary share and the ADSs may be evidenced by American Depositary Receipts, or ADRs.

We are concurrently offering 1,626,040 ordinary shares in Europe (including France) and countries outside of the United States in a private placement exclusively offered to “qualified investors,” as such term is defined in Article 2(e) of Regulation (EU) No. 2017/1129 of the European Parliament and Council of June 14, 2017, referred to herein as the European private placement.

This is our initial public offering of our ADSs in the United States. We have been approved to list our ADSs on the Nasdaq Global Market under the symbol “ABVX.” Our ordinary shares are listed on Euronext Paris under the symbol “ABVX.” On October 19, 2023, the last reported closing price of our ordinary shares on Euronext Paris was €11.78 per ordinary share, equivalent to a price of $12.44 per ADS, assuming an exchange rate of €0.9471 per U.S. dollar, the exchange rate on October 19, 2023 as reported by the European Central Bank.

The closings of the U.S. offering and the European private placement, which are together referred to as the global offering, will occur simultaneously. The total number of ordinary shares (including in the form of ADSs) in the U.S. offering and European private placement is subject to reallocation between these offerings, as permitted under applicable laws and regulations.

We are an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 and, as such, have elected to comply with certain reduced public company reporting requirements.

Investing in the ordinary shares and ADSs involves a high degree of risk. See “Risk Factors” beginning on page 17 of this prospectus.

Neither the Securities and Exchange Commission nor any U.S. state or other securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

We have granted an option to the underwriters, exercisable within 30 days from the date of this prospectus, to purchase up to an aggregate of 3,048,825 additional ADSs and/or ordinary shares (representing up to 15% of the initial size of the global offering) in the global offering to be sold to the several underwriters at the applicable offering price. If the underwriters exercise this option in full, the total underwriting commissions payable by us will be €18.0 million ($19.0 million) and the total proceeds to us, before expenses, will be €238.8 million ($252.2 million), based on the exchange rate on October 19, 2023.

The underwriters expect to deliver the ADSs to purchasers in the U.S. offering on or about October 24, 2023 through the book-entry facilities of The Depository Trust Company. The underwriters expect to deliver the ordinary shares to purchasers in the European private placement on or about October 24, 2023 through the book-entry facilities of Euroclear France.

The date of this prospectus is October 19, 2023.

TABLE OF CONTENTS

For investors outside the United States: Neither we nor any of the underwriters have done anything that would permit the global offering or possession or distribution of this prospectus in any jurisdiction where action for that purpose is required, other than in the United States. Persons outside the United States who come into possession of this prospectus must inform themselves about, and observe any restrictions relating to, the offering of the ordinary shares and ADSs and the distribution of this prospectus outside the United States.

We are incorporated in France, and under the rules of the U.S. Securities and Exchange Commission (the “SEC”), we are currently eligible for treatment as a “foreign private issuer.” As a foreign private issuer, we will not be required to file periodic reports and financial statements with the SEC as frequently or as promptly as domestic registrants whose securities are registered under the Securities Exchange Act of 1934, as amended (the “Exchange Act”).

Throughout this prospectus, references to ADSs mean ADSs or ordinary shares represented by ADSs, as the case may be.

MARKET, INDUSTRY AND OTHER DATA

Unless otherwise indicated, information contained in this prospectus concerning our industry and the markets in which we operate, including our general expectations and market position, market opportunity and market size estimates, is based on information from independent industry analysts, third-party sources and management estimates. Management estimates are derived from publicly available information released by independent industry analysts and third-party sources, as well as data from our internal research, and are based on assumptions made by us based on such data and our knowledge of such industry and market, which we believe to be reasonable. In addition, while we believe the market opportunity information included in this prospectus is reliable and is based on reasonable assumptions, such data involves risks and uncertainties and is subject to change based on various factors, including those discussed under the heading “Risk Factors.”

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PRESENTATION OF FINANCIAL INFORMATION

This prospectus includes our audited financial statements as of and for the years ended December 31, 2022 and 2021 prepared in accordance with International Financial Reporting Standards (“IFRS”), as issued by the International Accounting Standards Board (“IASB”). None of our financial statements were prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”).

Our financial statements are presented in euros and, unless otherwise stated, all monetary amounts are in euros. All references in this prospectus to “$”, “U.S. dollars” and “dollars” mean U.S. dollars, and all references to “€”, “EUR” and “euros” mean European Monetary Union euros, unless otherwise noted.

The European Union uses a flexible exchange rate system to determine the value of the euro against the U.S. dollar. The following table sets forth the rate of exchange for the euro at the end of the five most recent fiscal periods ended December 31, the average rates for the period, and the range of high and low rates for the period. The data for the six months ended June 30, 2023 is also included.

For purposes of this table, the rate of exchange means the closing daily rate used by the U.S. Department of Treasury. The table sets forth the number of euros required under that formula to buy one U.S. dollar. The average rate means the average of the exchange rates on the last day of each month during the period.

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TRADEMARKS AND SERVICE MARKS

“Abivax” and the Abivax logo and other trademarks or service marks of Abivax SA appearing in this prospectus are the property of Abivax SA. Solely for convenience, the trademarks, service marks and trade names referred to in this prospectus are listed without the ^® and ^™ symbols, but such references should not be construed as any indicator that their respective owners will not assert, to the fullest extent under applicable law, their right thereto. All other trademarks, trade names and service marks appearing in this prospectus are the property of their respective owners. We do not intend to use or display other companies’ trademarks and trade names to imply any relationship with, or endorsement or sponsorship of us by, any other companies.

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RISK FACTORS

An investment in our ordinary shares (including ordinary shares in the form of ADSs) involves a high degree of risk. You should carefully consider the risks and uncertainties described below, together with all of the information contained in this prospectus, including our financial statements and the related notes, before making an investment decision regarding the ordinary shares (including ordinary shares in the form of ADSs). If any of the following risks are realized, our business, financial condition, results of operations or prospects could be materially and adversely affected. In that event, the market price of our securities could decline, and you could lose part or all of your investment. The risks discussed below also include forward-looking statements, and our actual results may differ substantially from those discussed in these forward-looking statements. See “Cautionary Note Regarding Forward-Looking Statements.”

Risks Related to our Financial Position and Need for Additional Capital

We are a clinical-stage company with a limited operating history and no approved products and no historical product revenues, which makes it difficult to assess our future prospects and financial results.

We are a clinical-stage biopharmaceutical company with a limited operating history upon which you can evaluate our business and prospects. We were incorporated as a société anonyme (limited liability company) on December 4, 2013 and, to date, we have focused primarily on organizing and staffing our company, business planning, raising capital, identifying, acquiring and in-licensing our drug candidates, establishing our intellectual property portfolio, conducting research, preclinical studies and clinical trials, establishing arrangements with third parties for the manufacture of our drug candidates and related raw materials and providing general and administrative support for these operations. Investment in product development in the healthcare industry, including of biopharmaceutical products, is highly speculative because it entails substantial upfront capital expenditures and significant risk that any potential drug candidate will fail to demonstrate adequate effect or an acceptable safety profile, gain regulatory approval or become commercially viable. As a result, our ability to reduce our losses and reach consistent profitability from product sales is unproven, and we may never sustain profitability. We have no products approved for commercial sale and have not generated any revenue from product sales to date.

Our ability to generate revenue from product sales and achieve and maintain profitability depends on our ability, alone or with any future collaborators, to successfully complete the development of, and obtain the regulatory approvals necessary to commercialize, our lead drug candidate, obefazimod. Our prospects, including our ability to finance our operations and generate revenue from product sales, therefore will depend substantially on the development and commercialization of obefazimod, as other programs in our preclinical portfolio are still in earlier stages of development. Since our inception in 2013, the majority of our operating income has been derived from our reliance on research collaborations unrelated to obefazimod, and we do not anticipate generating revenue from product sales for the next several years, if ever. Our ability to generate revenue from product sales depends heavily on our or any future collaborators’ success in:

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We have incurred considerable losses historically, which we anticipate will continue and may increase in the future.

Since our inception, we have incurred net losses. For the six-month periods ended June 30, 2023 and 2022 and the years ended December 31, 2022 and 2021, we reported net losses of €52.0 million, €21.2 million, €60.7 million and €42.5 million, respectively. As of June 30, 2023, we carried forward accumulated tax losses of €355.4 million.

We have devoted most of our financial resources to research and development, including our clinical and preclinical development activities. Even if we obtain regulatory approval to market a drug candidate, our future revenues will depend upon the size of any markets in which our drug candidates have received approval and our ability to achieve sufficient market acceptance, reimbursement from third-party payors and adequate market share for our drug candidates in those markets. There can be no assurance that we will ever earn any revenues or revenues sufficient to offset past, current and future losses or achieve profitability, which would impair our ability to sustain our operations. Moreover, even if we achieve profitability, such profitability may not be sustainable. Any inability to generate sustained profits could have a material adverse effect on our business, prospects, financial condition, cash flows and results of operations.

We expect to continue to incur significant expenses and operating losses for the foreseeable future. We do not anticipate achieving profitability in the future unless we obtain the regulatory approvals necessary to commercialize obefazimod and any additional drug candidates that we may pursue in the future. We anticipate that our expenses will increase substantially if, and as, we:

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In addition, following the issuance of royalty certificates in September 2022 and other royalties that may become payable under our royalty agreements, the payment of royalties in the event of commercialization of obefazimod will result in a decrease in cash flows generated by sales of the product, which could have an unfavorable impact on our financial position, particularly at the beginning of the commercialization phase.

The net losses we incur may fluctuate significantly from quarter-to-quarter and year-to-year, such that a period-to-period comparison of our results of operations may not be a good indication of our future performance. In any particular period or periods, our operating results could be below the expectations of securities analysts or investors, which could cause the price of the ordinary shares (which may be in the form of ADSs) to decline. An increase in operational losses would have a material adverse effect on our business, financial position, income, growth and outlook.

Even if we consummate the offering, we will require substantial additional funding, which may not be available on acceptable terms or at all, and failure to obtain this necessary capital may force us to delay, limit or terminate our product development efforts or other operations.

Our operations have consumed substantial amounts of cash since inception. We are currently advancing obefazimod through clinical development and conducting preclinical studies with respect to other programs. Developing drug candidates is expensive, lengthy and risky, and we expect our research and development expenses to increase substantially in connection with our ongoing activities, particularly as we seek to advance obefazimod toward commercialization. If our clinical trials are successful and we obtain regulatory approval for drug candidates that we develop, we will incur commercialization expenses before these drug candidates are marketed and sold.

As of June 30, 2023, our cash and cash equivalents were €114.4 million. We believe that based on our current clinical plan and on our anticipated net proceeds from this offering, together with (a) our existing cash and cash equivalents of €114.4 million as of June 30, 2023, (b) the net proceeds of the August 2023 drawdown of the first tranches of the Kreos / Claret Financing and the Heights Financing, collectively amounting to €27.2 million (net of repayments of all outstanding amounts that remained due under the First KC Agreement, the Second KC Agreement and the OCEANE bonds), (c) the anticipated net proceeds from the drawdown of the second tranche of the Kreos / Claret Financing, amounting to €25 million (which is a portion of the total available drawdown of €65 million from the Kreos / Claret Financing and the Heights Financing) and (d) the expected Research Tax Credit (CIR) reimbursements would enable us to fund our operations through the fourth quarter of 2025. Under these assumptions and based on our current clinical plan, we would have sufficient funds to finance our operations through (i) the announcement of our top-line data from the Phase 3 ABTECT-1 and ABTECT-2 induction trials for UC and (ii) the announcement of our top-line data from the Phase 2a induction trial for CD.

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If we further draw down on the third tranche of the Kreos / Claret Financing, amounting to €25 million and the second tranche of the Heights Financing amounting to €40 million, we expect to have sufficient funds to finance our operations through the first quarter of 2026. Under these assumptions and based on our current clinical plan, we would have sufficient funds to finance our operations through the announcement of our top-line data from the Phase 3 ABTECT maintenance trial for UC. For additional details relating to the Kreos / Claret Financing and the Heights Financing, see “Business—Key Collaborations and Partners—Financing Arrangements.”

This takes into account our assumption that R&D expenditure will be substantially increased in 2023 driven by the progression of the Phase 3 clinical trials of obefazimod, which started enrollment of patients with moderately to severely active UC in October 2022. We have based this estimate on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we expect. For instance, there is no guarantee that we would be able to meet our conditions to be able to draw down on the remaining tranches of the Kreos / Claret Financing and the second tranche of the Heights Financing. We anticipate that we will require additional capital as we seek regulatory approval of our drug candidates. We intend to assess and plan for any such funding requirements and aim to regularly update the market on our financing need projections.

Until we can generate sufficient product or royalty revenue to finance our cash requirements, which we may never do, we may seek additional financing in the form of public or private equity or debt financings, government or other third-party funding, marketing and distribution arrangements and collaborations, strategic alliances and licensing arrangements or a combination of these sources.

The amount and timing of our funding needs will depend on factors that are largely outside of our control, such as:

Any additional fundraising efforts may divert our management from their day-to-day activities, which may adversely affect our ability to develop and, if approved, commercialize our drug candidates. In addition, we cannot guarantee that future financing will be available in sufficient amounts or on terms acceptable to us, if at all. Under French law, our share capital may be increased only with shareholders’ approval at an extraordinary general shareholders’ meeting on the basis of a report from the board of directors. In addition, the French Commercial Code imposes certain limitations on our ability to price certain offerings of our share capital without preferential subscription rights (droit préférentiel de souscription), which limitation may prevent us from successfully completing any such offering. See “Description of Share Capital—Rights, Preferences and Restrictions Attaching to Ordinary Shares (Articles 7, 11, 30, 31 and 32 of the By-Laws).” To the extent that we raise additional capital, the terms of any financing may adversely affect the holdings or the rights of our shareholders and the issuance of additional securities, whether equity or debt, by us, or the possibility of such issuance, may cause the market price of our ordinary shares (which may be in the form of ADSs) to decline. The sale of additional equity or convertible securities will dilute our shareholders ownership interest. The incurrence of indebtedness would result in increased fixed payment obligations and we may be required to agree to certain

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restrictive covenants, such as limitations on our ability to incur additional debt, limitations on our ability to acquire, sell or license intellectual property rights and other operating restrictions that could adversely impact our ability to conduct our business. To the extent that we raise additional funds through arrangements with research and development partners or otherwise, we may be required to relinquish some of our technologies, drug candidates or revenue streams, license our technologies or drug candidates on unfavorable terms, or otherwise agree to terms unfavorable for us. If we are unable to obtain adequate financing, we may be required to delay, reduce or eliminate the number or scope of our projects and drug candidates (including our preclinical studies and clinical trial programs). In order to obtain financing, we may be required to relinquish rights to some of our technologies or drug candidates or otherwise agree to terms unfavorable to us. If we are unable to obtain funding on a timely basis, we may be required to significantly curtail, delay or discontinue one or more of our research or development programs or the commercialization of any drug candidate or be unable to expand our operations or otherwise capitalize on our business opportunities, as desired, which could impair our prospects.

Our financial statements contain a footnote describing management’s assumption regarding our ability to continue as a going concern, which could prevent us from obtaining new financing on reasonable terms or at all.

Our independent registered public accounting firm included an emphasis of matter in its report that our financial statements, included elsewhere in this prospectus, have been prepared assuming that we will continue as a going concern. For the six-month periods ended June 30, 2023 and 2022 and the years ended December 31, 2022 and 2021, we reported net losses of €52.0 million, €21.2 million, €60.7 million and €42.5 million, respectively. As of June 30, 2023, we carried forward accumulated tax losses of €355.4 million. Recurring losses may cast significant doubt or raise substantial doubt about our ability to continue as a going concern.

There cannot be any assurance that we will be successful in obtaining necessary financing in the future to continue as a going concern or achieve profitability. We expect that we will need to raise additional capital following the completion of this equity offering in order to complete the necessary trials to achieve commercial viability of some or all of our drug candidates. If funds are not available, we may be required to delay, reduce the scope of, or eliminate research or development plans or commercialization efforts with respect to our products. The sale of additional equity may dilute existing shareholders and newly issued shares may contain senior rights and preferences compared to currently outstanding ordinary shares. Issued debt securities may contain covenants and limit our ability to pay dividends or make other distributions to our shareholders. If we are unable to obtain such additional financing, future operations (such as our clinical development programs) would need to be scaled back or discontinued. These factors may raise substantial doubt about our ability to continue as a going concern.

There are material weaknesses in our internal controls over financial reporting and if we are unable to maintain effective internal controls over financial reporting, the accuracy and timeliness of our financial reporting may be adversely affected, which could adversely affect our business, investor confidence and the market price of our securities.

Internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting for external purposes in accordance with international financial reporting standards. Internal control over financial reporting includes maintaining records that in reasonable detail accurately and fairly reflect our transactions; providing reasonable assurance that transactions are recorded as necessary for preparation of our financial statements; providing reasonable assurance that receipts and expenditures of our assets are made in accordance with management authorization; and providing reasonable assurance that unauthorized acquisition, use or disposition of our assets that could have a material effect on the financial statements would be prevented or detected on a timely basis. Because of its inherent limitations, internal control over financial reporting is not intended to provide absolute assurance that a misstatement of our financial statements would be prevented or detected.

We must maintain effective internal controls over financial reporting in order to accurately and timely report our results of operations and financial condition. In addition, as a public company listed in the United States, the

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Sarbanes-Oxley Act will require, among other things, that we assess the effectiveness of our internal controls over financial reporting at the end of each fiscal year, starting with the end of the first full fiscal year after the completion of the U.S. offering. However, our independent registered public accounting firm will not be required to attest to the effectiveness of our internal controls over financial reporting for so long as we are an “emerging growth company,” which may be up to five fiscal years following the date of this U.S. offering. An independent assessment of the effectiveness of our internal controls could detect problems that our management’s assessment might not.

Our management has not completed an assessment of the effectiveness of our internal controls over financial reporting, and our independent registered public accounting firm has not conducted an audit of our internal controls over financial reporting. In conjunction with preparing our financial statements as of and for the years ended December 31, 2022 and 2021 and as of and for the six-month period ended June 30, 2023 for this offering, material weaknesses in our internal controls over financial reporting were identified. The material weaknesses related to a lack of risk assessment as well as formal, documented and implemented processes, controls and review procedures, specifically due to a lack of a sufficient number of professionals with an appropriate level of internal control knowledge, training and experience. These material weaknesses did not result in a material misstatement to our financial statements included herein, however these material weaknesses could result in material inaccuracies in our financial statements and impair our ability to comply with applicable financial reporting requirements and related regulatory filings on a timely basis.

We are developing a remediation plan to address these material weaknesses and strengthen our controls in these areas. In this regard, we have started to reorganize our finance and accounting function by hiring additional experienced employees to provide more review and oversight over our financial processes. While we are working to remediate the material weaknesses as quickly and efficiently as possible, we cannot at this time provide the expected timeline in connection with implementing our remediation. As of June 30, 2023, we had not yet completed remediation of these material weaknesses. These remediation measures may be time-consuming and costly and might place significant demands on our financial and operational resources. There is no assurance that the actions we may take in the future will be sufficient to remediate the control deficiencies that led to these material weaknesses in our internal control over financial reporting or that they will prevent or avoid potential future material weaknesses.

The rules governing the standards that will have to be met for our management to assess our internal controls over financial reporting pursuant to Section 404 of the Sarbanes-Oxley Act are complex and require significant documentation, testing and possible remediation. These stringent standards require that our audit committee be advised and regularly updated on management’s review of internal controls over financial reporting. We have begun the process of designing, implementing, and testing the internal controls over financial reporting required to comply with this obligation. This process is time-consuming, costly, and complicated. Our management may not be able to effectively and timely implement controls and procedures that adequately respond to the increased regulatory compliance and reporting requirements that will be applicable to us as a public company listed in the United States. If we fail to staff our accounting and finance function adequately or maintain internal controls over financial reporting adequate to meet the demands that will be placed upon us as a public company listed in the United States, our business and reputation may be harmed and the price of our ordinary shares and ADSs may decline. In addition, undetected material weaknesses in our internal controls over financial reporting could lead to restatements of financial statements and require us to incur the expense of remediation. Any of these developments could result in investor perceptions of us being adversely affected, which could cause a decline in the market price of our securities.

Our management is responsible for establishing and maintaining adequate internal control over financial reporting. Our growth will place significant additional pressure on our system of internal control over financial reporting. Any failure to maintain an effective system of internal control over financial reporting could limit our ability to report our financial results accurately and timely or to detect and prevent fraud.

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Significant impairment of our goodwill could materially impact our financial position and results of our operations.

We carry a goodwill balance, which is allocated to obefazimod and ABX196 cash generating units, on our balance sheet as a result of past business acquisitions, including with respect to obefazimod and ABX196. We are required to review our goodwill for impairment on an annual basis or more frequently if events or changes in circumstances indicate evidence of impairment. For the year ended December 31, 2022, we recorded a goodwill impairment loss of €13.6 million. The goodwill impairment loss was related to an impairment test conducted with respect to the ABX196 cash-generating unit as a result of significant external changes in the hepatocellular carcinoma treatment landscape, which are expected to require a new, lengthy, heavy and risky internal development process (use of a combination of compounds). As such, due to the lack of progress made in the negotiation of a development partnership, we made the decision to freeze the development program for ABX196 in the treatment of hepatocellular cancer, which led to full impairment of ABX196 goodwill. In July 2023, we have decided to completely stop our ABX196 program, which will be reflected in our next financial statements. After full impairment of the goodwill allocated to ABX196, we continue to carry a goodwill balance allocated to obefazimod amounting to €18.4 million in the aggregate as of June 30, 2023. We have not currently identified reasons to impair the goodwill allocated to obefazimod. However, there can be no assurance that, based on the results of our annual goodwill impairment tests, we will not be required to identify further goodwill impairment losses, which could have a material adverse effect on our results of operations.

We have significant debt commitments, which require us to meet certain operating covenants, and if we fail to comply with those covenants the bondholders would be able to accelerate our repayment obligations. Additionally, the conversion of some or all of our bonds into ordinary shares would dilute the ownership interests of existing shareholders.

On August 20, 2023, we entered into the Framework Subscription Agreement with KC and Claret, as the Secured Lenders. Under this Framework Subscription Agreement, we may draw up to €75 million in structured debt financing, in three tranches of €25 million in aggregate principal amount each. The Kreos / Claret Financing provides for certain restrictive covenants (subject to customary exceptions), which include, among other things, restrictions on the incurrence of indebtedness, cross-default, the distribution of dividends and the grant of security interests. As security for the Kreos / Claret Financing, the Secured Lenders benefit from the grant of first-ranking collateral on our principal tangible and intangible assets, including pledges over our business (fonds de commerce) as a going concern and intellectual property rights in our lead drug candidate, as well as pledges over our bank accounts and receivables. Such securities apply to all tranches of the Kreos / Claret Financing.

In addition, on August 20, 2023, we entered into the Heights Subscription Agreement with Heights. Under the Heights Subscription Agreement, we may draw up to €75 million in amortizing senior convertible notes, in two tranches of €35 million and €40 million, respectively, as further described below. The terms and conditions of the Heights Convertible Notes include a negative pledge providing that any security granted in favor of other borrowed debt or debt instruments should also be granted in favor of the Heights Convertible Notes on an equal basis (with the exception of the securities issued pursuant to the Kreos / Claret Financing).

In June 2020, we obtained a non-dilutive financing in the form of a State-guaranteed loan of €5.0 million. The loan was structured with an initial maturity of 12 months at 0.25% and a five-year extension option. In March 2021, we exercised the five-year extension option with a one-year deferral of principal repayment, with the following conditions: (i) a revised interest rate of 0.58% per annum, excluding insurance and State-guaranteed premium; and (ii) a State-guaranteed premium of €0.1 million to be paid by installments over the contract period starting in June 2021.

The loan includes certain customary covenants and prepayment provisions. The negative covenants include an undertaking not to dispose of all or part of our assets for more than 50% of the gross value of our fixed assets.

There is also no guarantee that we will have sufficient cash to pay the bonds issued to the Secured Lenders or Heights at maturity, which could have a negative impact on our business as security interests have been

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granted on our principal tangible and intangible assets: in particular, on our goodwill, intellectual property rights relating to our lead drug candidates, as well as a pledge of our bank accounts and claims. There is also no guarantee that we will have sufficient cash to make the scheduled payments on the Kreos / Claret Financing, the Heights Financing or the State-guaranteed loan, which could have a material adverse effect on our business, financial position and results of operations. Any failure to make scheduled payments or trigger for early repayment of the loan could have a material adverse effect on our business, financial position, income, growth and outlook. If we breach our obligations under any of these agreements, it could result in default and trigger an early repayment of the bonds. There is no guarantee that we would have the necessary resources to fund an advance repayment of the bonds.

Our principal tangible and intangible assets serve as collateral under the terms of debt agreements for the Kreos / Claret Financing. If we default on these debt obligations, the Secured Lenders could foreclose on those assets, and we would be unable to continue our business and operations.

In August 2023, we entered into the Kreos / Claret Financing. In connection with the financing, we have granted the Secured Lenders with first-ranking collateral on our principal tangible and intangible assets, including pledges over our business (fonds de commerce) as a going concern and intellectual property rights in our lead drug candidate, as well as pledges over our bank accounts and receivables until our debt obligations thereunder are repaid in full. There can be no assurance that we will not breach the covenants or other terms of, or that an event of default will not occur under, the debt agreements for the Kreos / Claret Financing. If a breach or event of default occurs, there can be no assurance that we will be able to cure the breach within the time permitted. In the event of any failure to pay our obligations when due, any breach or default of our covenants or other obligations, or any other event that causes an acceleration of payment at a time when we do not have sufficient resources to meet these obligations, the Secured Lenders could foreclose on the collateral. If the Secured Lenders were to be successful, we would lose our intellectual property rights in our lead drug candidate and be unable to commercialize our lead drug candidate and conduct our business. Any of these consequences would have a material adverse effect on our business, financial condition and share price.

We rely on grants and subsidies, which may not continue to be available and we may be forced to repay conditional advances prematurely if we fail to comply with our contractual obligations under certain innovation grant agreements.

We have received various grants and conditional advances from Bpifrance under various development programs, in a total amount of €20.1 million as of December 31, 2022. In the event that we do not comply with the contractual conditions stipulated in the aid agreements we have entered into, we may have to repay the sums advanced early. Such premature repayment could deprive us of the necessary financial resources for our research and development projects and we cannot guarantee that we will find necessary additional financial resources, the timeline for or the possibility of replacing these financial resources with others. We cannot guarantee that we will have the necessary resources to cope with an early repayment. A material repayment would result in a material adverse effect on our business, operations, financial position, income, growth, and outlook.

In addition, the amount and date of payment of current and future grants and subsidies depend on many factors that are not in our control, including possible non-distribution decisions or the freezing of funds, as well as the achievement of key milestones previously agreed on with Bpifrance. Delays or failure in obtaining or replacing these grants and subsidies in the future could have a material adverse effect on our business, financial position, income, growth and outlook.

Current equity agreements and convertible debt instruments may dilute our equity resulting in dilution to our shareholders, including purchasers of our ordinary shares (including in the form of ADSs) in this offering.

Since our incorporation, we have issued and granted founder’s share warrants (BCE) and share warrants (BSA) and granted free shares (AGA) to persons linked to us and financing entities. We have also issued

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convertible bonds. See “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and Capital Resources.”

The theoretical exercise of all the founder’s share warrants (BCE) and share warrant (BSA) instruments giving access to our capital issued and outstanding as of June 30, 2023, excluding securities held by financing entities, would allow for the subscription of 731,893 potential new ordinary shares, resulting in a hypothetical dilution equal to 1.7% based on our existing share capital as of June 30, 2023.

The OCEANE bonds that were outstanding as of June 30, 2023 conferred an entitlement to subscribe for 769,834 ordinary shares, given the adjustment of the conversion parity on January 30, 2023 in accordance with the terms and conditions of the OCEANE bonds. The OCEANE bonds were repaid in full on August 24, 2023 and, therefore, may no longer be converted into new ordinary shares.

Furthermore, our general meeting of June 5, 2023 delegated authority to the board of directors (the “Board”) to carry out one or more capital increases and/or issues of securities giving access to our capital subject to the following limitations:

Using such delegation, we issued in August 2023 the following securities in connection with the Kreos / Claret Financing and the Heights Financing:

Our failure to maintain certain tax benefits applicable to French biopharmaceutical companies may adversely affect our operations and finances.

As a French biopharmaceutical company, we have benefited from certain tax advantages, including, for example, the Research and Development Tax Credit (crédit impôt recherche) (“CIR”), which is a French tax credit aimed at stimulating research and development. CIR can be offset against French corporate income tax due and the portion in excess, if any, may be refunded. CIR is calculated based on our claimed amount of eligible research and development expenditures in France and represents €4.5 million for 2022. The French tax authorities, with the assistance of the Higher Education and Research Ministry, may audit each research and development program in respect of which a CIR benefit has been claimed and assess whether such program qualifies in its view for the CIR benefit. The French tax authorities may challenge our eligibility for, or our calculation of, certain tax reductions or deductions in respect of our research and development activities and, should the French tax authorities be successful, our credits may be reduced, which would have a negative impact

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on our results of operations and future cash flows. Furthermore, the French Parliament may decide to eliminate, or to reduce the scope or the rate of, the CIR benefit, either of which it could decide to do at any time. If we fail to receive future CIR amounts, our business, prospects, financial condition, cash flows or results of operations could be adversely affected.

We may be unable to carry forward existing tax losses.

As of June 30, 2023, we carried forward accumulated tax losses of €355.4 million. In 2014, we acquired the companies Splicos, Wittycell and Zophis by means of a universal transfer of assets and liabilities. The tax losses carried forward of the three companies combined (Splicos, Wittycell and Zophis) amounted to €26.0 million on the date of the mergers and transfer of remaining assets. The transfer to us of these losses was subject to a post-merger approval by the French tax authorities, which approved the transfer of a total amount of €22.5 million. As a result of the transfer of these tax losses to us, our tax losses carried forward amounted to €308.8 million as at the end of 2022. To the extent we have continued conducting the business that led to these losses for a minimum period of three years, without making significant changes during this period, the transfer of such tax losses should be definitive. In France, the maximum amount of carried forward tax losses that can be written off against the tax profits of a given financial year is limited to €1 million plus 50% of the amount of taxable profits for the financial year exceeding €1 million. The outstanding tax losses remain valid and can be carried forward to be written off against tax profits of subsequent financial years subject to the same limit, for an unlimited period of time (subject to any “significant change of activity” at our level). It cannot be ruled out that regulatory or legislative changes in corporate taxation may suppress or limit all or part of the ability to use carried forward tax losses, or limit how long they can be used, to offset future profits. Changes in corporate taxation regarding the use of carried forward tax losses to offset future tax profits could have a material adverse effect on our financial position and results of operations.

Risks Related to Product Development, Regulatory Approval and Commercialization

Drug candidates under development must undergo costly, rigorous and highly regulated preclinical studies and clinical trials, whose time of completion, number and outcomes are uncertain.

The development of a drug candidate is a long and expensive process with an uncertain outcome, progressing in several phases, where the objective is to demonstrate the therapeutic benefit provided by the drug candidate for one or more indications. Any failure during the various preclinical and clinical phases for a given indication could delay development, production and commercialization of the therapeutic product concerned or even lead to discontinuing its development. Identifying potential drug candidates and conducting preclinical testing and clinical trials is a time-consuming, expensive and uncertain process that takes years to complete, and we may never generate the data or required results required to obtain regulatory approval and achieve commercialization.

During clinical trials, we may encounter difficulties determining and recruiting patients with the appropriate profile. This profile could also vary depending on the different phases of these clinical trials. Patients might then not be recruited according to a timetable compatible with our financial resources which may result in a harm to our operation results.

At each phase of clinical development, we must ask for authorization from the relevant authorities of various countries, according to our development plan, to conduct clinical trials and then present the results of the clinical trials to these authorities. The authorities may refuse to provide the authorizations necessary for clinical trials or have additional requirements (for example, relating to study protocols, patient characteristics, treatment durations, post-treatment follow-up, certain differences in interpreting results between local regulatory agencies), and in some cases may require additional studies. Any refusal or decision by health authorities to require additional trials or examinations would be likely to result in the discontinuation or delay of the development of the products concerned. An absence of or delay in therapeutic response could also result in the delay or even discontinuation of the development of our drug candidates.

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We cannot guarantee that the development of our drug candidates will ultimately be successful, especially within time frames compatible with our financial resources or market needs. Any failure or delay in the development of these products would have a material adverse effect on our business, income, financial position and outlook.

We are developing drug candidates for inflammatory diseases. To our knowledge, currently, there are no similar immunological treatments with a mechanism of action based on enhanced expression of a single microRNA miR-124, with marketing authorization granted by competent regulatory authorities. As a result, the outlook is uncertain for the development and profitability of obefazimod in the area of inflammatory diseases, its efficacy and acceptance by patients, doctors and paying agencies. Animal testing does not necessarily predict the results that will be obtained in humans. Positive results for obefazimod during Phase 1, Phase 2b or Phase 3 clinical trials or those for all the products in the portfolio during their research or preclinical phases might not be confirmed by subsequent phases. Such outcomes could have a material adverse impact on our business, income, financial position and growth.

We are heavily dependent on the success of our drug candidates, in particular obefazimod, and we cannot be certain that obefazimod or any of our other current or future drug candidates will receive regulatory approval, and, without regulatory approval, we will not be able to market our drug candidates.

We currently have no drug candidates approved for sale, and we cannot guarantee that we will ever have marketable drug candidates. Our ability to generate revenue related to sales, if any, will in the near future depend entirely on the successful development and regulatory approval of obefazimod. In Europe and the United States, as well as in many other countries, access to the drug market is controlled and marketing must be authorized by a regulatory authority. Most of the time, this registration application is filed with a national health authority, except in the case of the European Union, where a centralized procedure for reviewing marketing authorization application (“MAA”) managed by the European Medicines Agency (“EMA”) exists for specific kind of medicinal products.

The research, testing, manufacturing, safety, efficacy, labeling, approval, sale, marketing and distribution of our drug candidates are, and will remain, subject to comprehensive and extensive regulation by the EMA in the European Union, the Food and Drug Administration (“FDA”) in the United States, the Pharmaceuticals and Medical Devices Agency (“PMDA”) in Japan and regulatory authorities in other countries, with regulations differing from country to country. Subject to limited exceptions, we are not permitted to market our drug candidates in the European Union, the United States or Japan until we receive approval of an MAA from the European Commission or (a) Member State(s) authority(ies) or a new drug application (“NDA”) from the FDA or the PMDA. We have not submitted any marketing applications for any of our drug candidates. Regulators of each jurisdiction have their own procedures for approval of drug candidates. Failure to obtain regulatory approval for our drug candidates in any jurisdiction will prevent us from commercializing and marketing our drug candidates in such jurisdictions, and marketing authorizations may be granted for narrow indications which may significantly reduce the market of our drug candidates.

Obtaining and maintaining marketing authorization, by country or by geographical area in the case of the European Union, presupposes compliance with the mandatory standards imposed by the regulatory authorities and submission to the authorities of a great deal of information about the new product regarding its toxicity, dosage, quality, efficacy and safety all over its life cycle. The authorization process is long and expensive, and the result of this process remains uncertain. We are therefore careful to continuously comply with good practices in order not to jeopardize our chances of ultimately obtaining, directly or via our business partners, marketing authorization for the products we are developing. Obtaining marketing authorization in a given country or geographical area does not automatically ensure or immediately lead to obtaining marketing authorization in other countries.

In order to obtain marketing authorization for one of our products, we may have to perform preclinical animal studies and complete human clinical trials in order to demonstrate the safety and efficacy of the product.

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In the event patients are exposed to unforeseen and serious risks, we or the regulatory authorities may choose to suspend or terminate these clinical trials.

MAAs, NDAs and similar authorizations must include extensive preclinical and clinical data and supporting information to establish the drug candidate’s safety and effectiveness for each desired indication. NDAs, MAAs and similar authorizations must also include significant information regarding the chemistry, manufacturing and controls for the drug. Obtaining approval of a MAA or a NDA is a lengthy, expensive and uncertain process, and we may not be successful in obtaining approval. The EMA, Member States national authorities, FDA and PMDA review processes can take years to complete and approval is never guaranteed. If we submit an NDA to the FDA, the FDA must decide whether to accept or reject the submission for filing. We cannot be certain that any submissions will be accepted for filing and review by the FDA. Regulators of other jurisdictions, such as the EMA and the PMDA, have their own procedures for the scientific evaluation or approval of drug candidates.

Even if a drug is approved, the FDA, the EMA or the PMDA, as the case may be, may limit the indications for which the drug may be marketed, require extensive warnings on the drug labeling or require expensive and time-consuming clinical trials or reporting as conditions of approval. Regulatory authorities in countries outside the European Union, the United States and Japan also have requirements for approval of drug candidates with which we must comply prior to marketing in those countries. Obtaining regulatory approval for marketing of a drug candidate in one country does not ensure that we will be able to obtain regulatory approval in any other country. In addition, delays in approvals or rejections of marketing applications in the European Union, the United States or other countries may be based upon many factors, including regulatory requests for additional analyses, reports, data, preclinical studies and clinical trials, regulatory questions regarding different interpretations of data and results, changes in regulatory policy during the period of drug development and the emergence of new information regarding our drug candidates or other drug candidates.

Even if we receive regulatory approval for any drug candidate, we will be subject to ongoing regulatory obligations and continued regulatory review, which may result in significant additional expense

Even if we receive approval of any of our drug candidates, such regulatory approval may be withdrawn, or such approvals may be contingent on ongoing obligations and continued regulatory review, which may result in significant additional expense. As a general matter, any regulatory approvals that we may receive for our drug candidates, the manufacturing processes, labeling, packaging, distribution, adverse event reporting, storage, advertising, promotion, import, export and recordkeeping for our drug candidates will be subject to extensive and ongoing regulatory requirements. These requirements include submissions of safety and other post-marketing information and reports, registration, as well as ongoing compliance with current Good Manufacturing Practice (“GMP”) and Good Clinical Practice requirements (“GCPs”) for any clinical trials that we may continue to conduct. In addition, manufacturers of drug products and their facilities are subject to continual review and periodic, unannounced inspections by the FDA and other regulatory authorities for compliance with GMP regulations and standards. In addition, any regulatory approvals we may receive will require the submission of reports to regulatory authorities and surveillance to monitor the safety and efficacy of the drug candidate.

Additionally, our drug candidates, even if approved, may include limitations related to use restrictions for specified age groups, warnings, precautions or contraindications, and may include burdensome post-approval study or risk management requirements. For example, the FDA may require a risk evaluation and mitigation strategy (“REMS”) as a condition of approval of our drugs candidates, which could include requirements for a medication guide, physician training and communication plans or additional elements to ensure safe use, such as restricted distribution methods, patient registries and other risk minimization tools.

We may need to maintain or obtain a Good Manufacturing Practice (“GMP”) certificate in order to produce the immunotherapies that we are developing (for clinical trial purposes or during the commercialization phase). We cannot guarantee that we will obtain or be able to maintain this certificate, nor that certain additional constraints related to this certificate will not be imposed on us in the future. Any failure to follow and document

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adherence to such GMP regulations or other regulatory requirements may lead to significant delays in the availability of products for commercial sale or clinical trials, may result in the termination of or a hold on a clinical trial, or may delay or prevent filing or approval of marketing applications for our products. Failure to comply with applicable regulations could also result in the FDA or other applicable regulatory authorities taking various actions, including:

The FDA generally requires two adequate and well-controlled clinical trials to support approval. In addition, we must scale up manufacturing and complete other standard preclinical studies and clinical trials. We cannot predict whether our future trials will be successful or whether regulators will agree with our conclusions regarding the preclinical studies and clinical trials we have conducted to date and will conduct in the future.

Failure to obtain authorization for our drug candidates in one or more jurisdictions, particularly in respect of our lead drug candidate, obefazimod, would have a material adverse effect on our business, outlook, financial position, results and development.

Our drug candidates may cause undesirable side effects or have other properties that could delay or prevent their regulatory approval, or, if approval is received, require our drug candidates to be withdrawn from the market, require them to include safety warnings or otherwise limit their sales.

Undesirable side effects caused by our drug candidates could cause us or regulatory authorities to interrupt, delay or halt clinical trials, or even discontinuation and could result in a more restrictive label or the delay or denial of regulatory approval by the European Commission, FDA, PDMA or other comparable authorities in other jurisdictions. If severe side effects were to occur, or if one of our drug candidates is shown to have other unexpected characteristics, we may need to either restrict the use of such product to a smaller population or abandon development of such drug candidates.

If one or more of our drug candidates received marketing approval, and we or others later identify undesirable side effects caused by such drugs or negative interactions with other products or treatments (including, for example, as a result of interactions with other products once on the market), a number of potentially significant negative consequences could result, including:

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Any of these events could prevent us from achieving or maintaining market acceptance of the particular drug candidate, if approved, and could have a material adverse effect on our business, prospects, financial condition, cash flows or results of operations.

Clinical failure can occur at any stage of clinical development. The results of earlier clinical trials as well as data from any interim analysis of ongoing trials are not necessarily predictive of future results and any drug candidate we advance through clinical trials may not have favorable results in later clinical trials.

Clinical testing is expensive and can take many years to complete, and its outcome is inherently uncertain. Clinical failure can occur at any stage of our clinical development. Success in preclinical studies and early clinical trials, as well as data from any interim analysis of ongoing trials do not ensure that subsequent clinical trials will generate the same or similar results. A number of companies in the pharmaceuticals industry, including those with greater resources and experience than us, have suffered significant setbacks in Phase 3 clinical trials, even after seeing promising results in earlier clinical trials, and we could face similar setbacks. In some instances, there can be significant variation in safety or efficacy results between different clinical trials of the same drug candidate due to numerous factors, including changes in trial procedures set forth in protocols, differences in the size and type of the patient populations, changes in and adherence to the dosing regimen and other clinical trial protocols and the rate of dropout among clinical trial participants. Moreover, data obtained from preclinical and clinical activities is subject to varying interpretations, which may delay, limit or prevent regulatory approval. Any such delays or failures could negatively impact our business, financial condition, results of operation and prospects. The positive results generated in preclinical and clinical trials for obefazimod does not ensure that current or future trials will continue to demonstrate similar safety and/or efficacy results.

Drug candidates in later stages of clinical trials may fail to show the desired safety and efficacy traits despite having progressed through preclinical studies and earlier clinical trials. In addition to the safety and efficacy traits of any drug candidate, clinical trial failures may result from a multitude of factors including flaws in trial design, dose selection, placebo effect and patient enrollment criteria. Based upon negative or inconclusive results, we or our collaborators may decide, or regulators may require us, to conduct additional clinical trials or preclinical studies. Further, data obtained from trials and studies are susceptible to varying interpretation, and regulators may not interpret our data as favorably as we do, which may delay, limit or prevent regulatory approval.

We cannot guarantee the commercial success of the drug candidates that we develop.

If we or one or more of our commercial partners succeeds in obtaining marketing authorization, allowing us or them to market the therapeutic products developed by us, it may nevertheless take time to gain the support of the medical community, health care providers and third-party payers.

The level of market acceptance for each of our products will depend on several factors, notably on the following:

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Although the products we are developing are intended to provide a therapeutic response to a need that is presently unmet, poor market penetration resulting from one or more of the factors described above would have a negative impact on their commercialization and on our ability to generate profits, which could have a material adverse effect on our business, outlook, financial position, income and growth.

Our future may depend on our most advanced clinical development program, obefazimod, since our other drug candidates are in a less advanced stage of development.

Obefazimod is our most advanced drug candidate. Obefazimod has required, and may continue to require, significant investments of our time and financial resources, as well as the special attention of highly qualified staff. Consequently, if we were unable to obtain conclusive results in ongoing maintenance trials, Phase 3 of obefazimod in UC or Phase 2 of obefazimod in CD, it could have a material adverse effect on our business, outlook, financial position, results and development.

We may experience setbacks that could delay or prevent regulatory approval of our drug candidates or our ability to commercialize any products, including:

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We do not have complete control over many of these factors, including certain aspects of clinical development and the regulatory submission process, potential threats to our intellectual property rights and our manufacturing, marketing, distribution and sales efforts or that of any future collaborator.

We may find it difficult to enroll patients in our clinical trials. If we encounter difficulties enrolling patients in our clinical trials, our clinical development activities could be delayed or otherwise adversely affected.

Patient enrollment is a significant factor in the timing of clinical trials, and the timing of our clinical trials will depend, in part, on the speed at which we can recruit patients to participate in our trials, as well as completion of required follow-up periods. We may not be able to initiate or continue clinical trials for our drug candidates if we are unable to locate and enroll a sufficient number of eligible patients to participate in these trials to such trial’s conclusion as required by applicable regulatory authorities. The eligibility criteria of our clinical trials, once established, may further limit the pool of available trial participants.

Patient enrollment in clinical trials may be affected by other factors, including:

Additionally, other pharmaceutical companies targeting these same diseases are recruiting clinical trial patients from these patient populations, which may make it more difficult to fully enroll any clinical trials. We also rely on, and will continue to rely on, CROs and clinical trial sites to ensure proper and timely conduct of our clinical trials and preclinical studies. Though we have entered into agreements governing their services, we will have limited influence over their actual performance. Our inability to enroll a sufficient number of patients for our clinical trials would result in significant delays or may require us to abandon one or more clinical trials altogether. Enrollment delays in our clinical trials may result in increased development costs for our drug candidates and jeopardize our ability to obtain regulatory approval for the sale of our drug candidates. Furthermore, even if we are able to enroll a sufficient number of patients for our clinical trials, we may have difficulty maintaining enrollment of such patients in our clinical trials.

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We are developing certain of our drug candidates in combination with other therapies, and safety or supply issues with combination use products may delay or prevent development and approval of our therapeutic candidates.

We are developing certain of our drug candidates in combination with one or more approved or investigational therapies. Even if any drug candidate we develop were to receive marketing approval or be commercialized for use in combination with other existing therapies, we would continue to be subject to the risks that the FDA, European Commission, PDMA or similar foreign regulatory authorities could revoke approval of the therapy used in combination with our product or that safety, efficacy, manufacturing or supply issues could arise with any of those existing therapies. If the therapies we use in combination with our drug candidates are replaced as the standard of care for the indications we choose for any of our drug candidates, the EMA, FDA, PDMA or similar foreign regulatory authorities outside may require us to conduct additional clinical trials. The occurrence of any of these risks could result in our own products, if approved, being removed from the market or being less successful commercially.

We also may evaluate our drug candidates in combination with one or more therapies that have not yet been approved for marketing by the FDA, European Commission, PDMA or similar foreign regulatory authorities. We will not be able to market and sell any drug candidate we develop in combination with an unapproved therapy if that unapproved therapy does not ultimately obtain marketing approval. In addition, unapproved therapies face the same risks described with respect to our drug candidates currently in development, including the potential for serious adverse effects, delay in their clinical trials and lack of FDA, European Commission, or PDMA, or similar foreign regulatory authorities or PDMA approval.

If the FDA, European Commission or similar foreign regulatory authorities do not approve these other therapies or revoke their approval of, or if safety, efficacy, manufacturing or supply issues arise with, the therapies we choose to evaluate in combination with our drug candidates, we may be unable to obtain approval of or market any such drug candidate.

We may conduct clinical trials for our drug candidates outside of the U.S., and the FDA may not accept data from such trials, in which case our development plans may be delayed, which could materially harm our business.

We have in the past conducted clinical trials or a portion of our clinical trials for our drug candidates outside the U.S. The acceptance of study data from clinical trials conducted outside the U.S. or another jurisdiction by the FDA or comparable foreign regulatory authority may be subject to certain conditions or may not be accepted at all. In cases where data from foreign clinical trials are intended to serve as the sole basis for marketing approval in the U.S., for example, the FDA will generally not approve the application on the basis of foreign data alone unless (i) the data are applicable to the U.S. population and U.S. medical practice; (ii) the trials were performed by clinical investigators of recognized competence and pursuant to GCP regulations; and (iii) the data may be considered valid without the need for an on-site inspection by the FDA, or if the FDA considers such inspection to be necessary, the FDA is able to validate the data through an on-site inspection or other appropriate means. In addition, even where the foreign study data are not intended to serve as the sole basis for approval, the FDA will not accept the data as support for an application for marketing approval unless the study is well-designed and well-conducted in accordance with GCP requirements and the FDA is able to validate the data from the study through an onsite inspection if deemed necessary. Many foreign regulatory authorities have similar requirements for clinical data gathered outside of their respective jurisdictions. In addition, such foreign trials would be subject to the applicable local laws of the foreign jurisdictions where the trials are conducted. There can be no assurance that the FDA or any comparable foreign regulatory authority will accept data from trials conducted outside of the U.S. or the relevant jurisdiction. If the FDA or any comparable foreign regulatory authority does not accept such data, it may result in the need for additional trials, which could be costly and time-consuming, and which may result in current or future drug candidates that we may develop not receiving approval for commercialization in the applicable jurisdiction.

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Interim, “top-line” and preliminary data from our clinical trials and preclinical studies that we announce or publish from time to time may change as more patient data become available and are subject to audit and verification procedures that could result in material changes in the final data.

From time to time, we may publicly disclose interim, top-line or preliminary data from our clinical trials and preclinical studies, which is based on a preliminary analysis of then-available data, and the results and related findings and conclusions are subject to change following a more comprehensive review of the data related to the particular study or trial. We also make assumptions, estimations, calculations and conclusions as part of our analyses of data, and we may not have received or had the opportunity to fully and carefully evaluate all data. As a result, the interim, top-line or preliminary results that we report may differ from future results of the same studies or trials, or different conclusions or considerations may qualify such results, once additional data have been received and fully evaluated. Top-line and preliminary data also remain subject to audit and verification procedures that may result in the final data being materially different from the top-line or preliminary data we previously published. As a result, top-line and preliminary data should be viewed with caution until the final data are available.

Interim data from clinical trials that we may complete are further subject to the risk that one or more of the clinical outcomes may materially change as patient enrollment continues and more patient data become available. Adverse differences between interim, top-line or preliminary data and final data could significantly harm our business prospects. Further, disclosure of such data by us or by our competitors could result in volatility in the price of our securities.

Further, others, including regulatory agencies, may not accept or agree with our assumptions, estimates, calculations, conclusions or analyses or may interpret or weigh the importance of data differently, which could impact the value of the particular program, the approvability or commercialization of the particular drug candidate or product and our company in general. In addition, the information we choose to publicly disclose regarding a particular study or clinical trial is based on what is typically extensive information, and you or others may not agree with what we determine is material or otherwise appropriate information to include in our disclosure, and any information we determine not to disclose may ultimately be deemed significant with respect to future decisions, conclusions, views, activities or otherwise regarding a particular drug candidate or our business. If the interim, top-line or preliminary data that we report differ from actual results, or if others, including regulatory authorities, disagree with the conclusions reached, our ability to obtain approval for, and commercialize, our drug candidates may be harmed, which could harm our business, operating results, prospects or financial condition.

Disruptions at the FDA and other government agencies caused by funding shortages or global health concerns could hinder their ability to hire, retain or deploy key leadership and other personnel, prevent new or modified products from being developed, review, approved or commercialized in a timely manner or at all, which could negatively impact our business.

The ability of the FDA and foreign regulatory authorities to review and approve new products can be affected by a variety of factors, including government budget and funding levels, statutory, regulatory and policy changes, the FDA’s or foreign regulatory authorities’ ability to hire and retain key personnel and accept the payment of user fees, and other events that may otherwise affect the FDA’s or foreign regulatory authorities’ ability to perform routine functions. Average review times at the FDA and foreign regulatory authorities have fluctuated in recent years as a result. In addition, government funding of other government agencies that fund research and development activities is subject to the political process, which is inherently fluid and unpredictable. Disruptions at the FDA and other agencies, such as the EMA following its relocation to Amsterdam and resulting staff changes, may also slow the time necessary for new drugs or modifications to approved drugs and to be reviewed and/or approved by necessary government agencies, which would adversely affect our business. For example, over the last several years, the U.S. government has shut down several times and certain regulatory agencies, such as the FDA, have had to furlough critical FDA employees and stop critical activities.

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Separately, in response to the global COVID-19 pandemic, the FDA postponed most inspections of domestic and foreign manufacturing facilities at various points. Even though the FDA has since resumed standard inspection operations of domestic facilities where feasible, the FDA has continued to monitor and implement changes to its inspectional activities to ensure the safety of its employees and those of the firms it regulates, and any resurgence of the virus or emergence of new variants may lead to further inspectional delays. Regulatory authorities outside the United States have adopted similar policy measures in response to COVID-19. If a prolonged government shutdown occurs, or if global health concerns prevent the FDA or other regulatory authorities from conducting their regular inspections, reviews, or other regulatory activities, it could significantly impact the ability of the FDA or other regulatory authorities to timely review and process our regulatory submissions, which could have a material adverse effect on our business.

The FDA and other regulatory agencies actively enforce the laws and regulations prohibiting the promotion of off-label uses.

The FDA strictly regulates marketing, labeling, advertising and promotion of prescription drugs. These regulations include standards and restrictions for direct-to-consumer advertising, industry-sponsored scientific and educational activities, promotional activities involving the internet and off-label promotion. Any regulatory approval that the FDA grants is limited to those specific diseases and indications for which a product is deemed to be safe and effective by FDA. While physicians in the United States may choose, and are generally permitted, to prescribe drugs for uses that are not described in the product’s labeling and for uses that differ from those tested in clinical trials and approved by the regulatory authorities, our ability to promote any products will be narrowly limited to those indications that are specifically approved by the FDA.

If we are found to have promoted such off-label uses, we may become subject to significant liability. The U.S. federal government has levied large civil and criminal fines against companies for alleged improper promotion of off-label use and has enjoined several companies from engaging in off-label promotion. The FDA has also requested that companies enter into consent decrees or permanent injunctions under which specified promotional conduct is changed or curtailed. If we cannot successfully manage the promotion any drug candidates, if approved, we could become subject to significant liability, which would materially adversely affect our business and financial condition.

We may not be able to find industrial partners to pursue the clinical and commercial development of obefazimod.

We aim to enter into licensing and distribution partnerships with pharmaceutical companies in order to fund the completion of the clinical development and marketing preparation of our lead drug candidate, obefazimod. Consequently, we should find partners with sufficient capacity to perform Phase 1, 2 and/or 3 clinical trials on a national or international scale and mass-produce, distribute and market immunotherapies and anti-inflammatory treatments such as obefazimod. If we were to enter into such partnerships, the commercialization of our products would depend, in part, on the clinical, industrial, marketing and commercial development efforts of our business partners and the ability of these partners to produce and sell obefazimod. Any failure on the part of our partners could have a material adverse effect on our growth and outlook.

It is also possible that we may not be able to enter into partnerships under economically reasonable conditions or at all. This could have a material adverse effect on our business, outlook, financial position, results and development.

We may not be able to conduct, or contract others to conduct, animal testing in the future, which could harm our research and development activities.

Certain laws and regulations relating to drug development require us to test our drug candidates on animals before initiating clinical trials involving humans. Animal testing activities have been the subject of controversy

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and adverse publicity. Animal rights groups and other organizations and individuals have attempted to stop animal testing activities by pressing for legislation and regulation in these areas and by disrupting these activities through protests and other means. To the extent the activities of these groups are successful, our research and development activities may be interrupted or delayed.

Risks Related to our Operations and Strategic Development

We expect to expand our organization, and as a result, we may encounter difficulties in managing our growth, which could disrupt our operations.

In order to manage our anticipated development and expansion, including the potential commercialization of our drug candidates in Europe and the United States we must continue to implement and improve our managerial, operational and financial systems, expand our facilities and continue to recruit and train additional qualified personnel. Due to our limited financial resources and the limited experience of our management team in managing a company with such expected growth, we may not be able to effectively manage the expansion of our operations or recruit and train additional qualified personnel. The expansion of our operations may lead to significant costs and may divert the attention of our management and business development resources away from day-to-day activities and devote a substantial amount of time to managing internal or external growth. Our inability to manage growth or unexpected difficulties encountered during expansion could have a material adverse effect on our business, income, financial position, growth and outlook.

Our international operations subject us to various risks, and our failure to manage these risks could adversely affect our results of operations.

We face significant operational risks as a result of doing business internationally, such as:

The market opportunities for our drug candidates may be limited to patients who are ineligible for or have failed prior treatments and may be small or different from our estimates.

The current IBD treatment approach is influenced by multiple factors, including disease severity, previous response to treatment, side effects and co-morbidities. The current standard of care for treatment of patients with mild IBD involves the use of conventional anti-inflammatory therapies. Conventional anti-inflammatory

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therapies include: aminosalicylates (e.g., 5-ASA), immunosuppressants or immunomodulators (e.g., 6-mercaptopurine (“6-MP”), methotrexate (“MTX”)) and corticosteroids that are usually prescribed for short-term treatment to manage flare-ups. Despite these conventional therapies, patients suffering from mild IBD may evolve towards moderate and severe forms of IBD requiring the use of advanced therapies. However, available therapies often only have moderate efficacy that changes or may wane over time, as patients have the potential to stop responding or do not respond at all to these treatments and thus require new therapeutic management options.

While we hope to position obefazimod as a potential first-line advanced therapy, there is no guarantee that even if approved, it would be approved for first-line advanced therapy. This could limit our potential market opportunity. In addition, we may have to conduct additional clinical trials prior to gaining approval for first-line advanced therapy.

The estimates of market opportunity and forecasts of market growth included in this prospectus may prove to be inaccurate, and even if the markets in which we compete achieve the forecasted growth, our business may not grow at similar rates, or at all.

Market opportunity estimates and growth forecasts included in this prospectus are subject to significant uncertainty and are based on assumptions and estimates which may not prove to be accurate. The estimates and forecasts included in this prospectus relating to size and expected growth of our target market may prove to be inaccurate. Even if the markets in which we compete meet the size estimates and growth forecasts included in this prospectus, our business may not grow at similar rates, or at all. Our growth is subject to many factors, including our success in implementing our business strategy, which is subject to many risks and uncertainties.

Sales of our drug candidates could be adversely impacted by the reluctance of physicians, healthcare payors, patients or the medical community in general to adopt them and by the availability of competing drugs.

Even if we obtain regulatory approval for one or more of our drug candidates, physicians, healthcare payors, patients or the medical community in general may be reluctant to try a new drug due to the high degree of risk associated with the application of new drugs in the field of human medicine, especially if the new drug differs from the currently prevailing medication for a given complaint. We will need to expend significant sums of money to market our products to increase the public’s awareness within numerous limits set by the regulations concerning the promotion of drugs. If our products do not achieve an adequate level of acceptance, we may not generate enough revenues to become profitable or the profitability may occur much later.

Competing drug candidates in the chronic inflammatory disease field are being manufactured and marketed by other companies, including, but not limited to, AbbVie, Pfizer, Eli Lilly, Takeda and Johnson & Johnson. To compete with other drugs, particularly any that sell at lower prices, our drug candidates will have to provide medically significant advantages or be more cost-effective. Even if we can overcome physician reluctance and compete with products that are currently on the market, our competitors may succeed in developing new, safer, more accurate or more cost-effective treatments or therapeutic indications that could render our drug candidates obsolete or non-competitive.

Global economic conditions could materially adversely impact demand for our drug candidates.

Our operations and performance depend significantly on economic conditions. Global financial conditions continue to be subject to volatility arising from international geopolitical developments, such as the war in Ukraine and global economic phenomena, as well as general financial market turbulence, natural phenomena and any public health outbreak. Uncertainty about global economic conditions could result in:

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either of which could, accordingly, have a material adverse effect on our business, results of operations or financial condition.

Access to public financing and credit can be negatively affected by the effect of these events on European, U.S. and global credit markets. The health of the global financing and credit markets may affect our ability to obtain equity or debt financing in the future and the terms at which financing or credit is available to us. These instances of volatility and market turmoil could adversely affect our operations and the trading price of our ordinary shares.

Changes to trade policy, tariffs, and import/export regulations may have a material adverse effect on our business, financial condition, and results of operations.

Changes in laws and policies governing foreign trade could adversely affect our business. As a result of recent and future policy changes, there may be greater restrictions and economic disincentives on international trade. Such changes have the potential to adversely impact the global and local economies, our industry and global demand for our drug candidates and, as a result, could have a material adverse effect on our business, financial condition and results of operations.

Fluctuations in currency exchange rates may significantly impact our results of operations.

Our business is located, and our operations are conducted, in Europe. As a result, we are exposed to an exchange rate risk between the U.S. dollar and the Euro. The exchange rates between these currencies in recent years have fluctuated significantly and may continue to do so in the future. An appreciation of the Euro against the U.S. dollar could increase the relative cost of our drug candidates outside of Europe, which could have a negative effect on sales. Conversely, to the extent that we are required to pay for goods or services in U.S. dollars, the depreciation of the Euro against the U.S. dollar would increase the cost of such goods and services.

We do not hedge our currency exposure and, therefore, we incur currency transaction risk whenever we enter into either a purchase or sale transaction using a currency other than the Euro. Given the volatility of exchange rates, we might not be able to effectively manage our currency transaction risks, and volatility in currency exchange rates might have a material adverse effect on our business, financial condition or results of operations.

We rely on a small number of third-party suppliers and manufacturers, and in certain cases a single-source supplier, and we may be in a position of dependence with respect to these third parties.

We do not own or operate manufacturing facilities and have no current plans to develop our own clinical or commercial-scale manufacturing capabilities. We currently rely, and expect to continue to rely, on a small number of third-party suppliers, and in certain cases a single-source supplier, for the supply of various raw materials and chemical products and clinical batches needed for our preclinical studies and clinical trials. In the case of certain manufactured and clinical supplies, we rely on single-source suppliers. The supply of specific raw materials and products required for conducting clinical trials and manufacturing our products cannot be guaranteed.

We are dependent on third parties for the supply of various materials, including chemical or biological products that are necessary to produce drug candidates for our clinical trials and, ultimately, commercial supply for any of our drug candidates that may receive approval.

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The facilities used by our third-party manufacturers must be approved for the manufacture of our drug candidates by the FDA, the EMA and any comparable foreign regulatory authorities in other jurisdictions, pursuant to inspections that will be conducted after we submit an NDA to the FDA, MAA to the EMA, or submit a comparable marketing application to a comparable regulatory authority. We do not control the manufacturing process of, and are completely dependent on, third-party manufacturers for compliance with GMP requirements for manufacture of our drug candidates. If these third-party manufacturers cannot successfully manufacture material that conforms to our specifications and the strict regulatory requirements of any applicable regulatory authority, they will not be able to secure and/or maintain regulatory approval for the use of their manufacturing facilities.

In addition, we have no control over the ability of third-party manufacturers to maintain adequate quality control, quality assurance and qualified personnel. If any regulatory authority does not approve these facilities for the manufacture our drug candidates, or if such authorities withdraw any such approval in the future, we may be required to find alternative manufacturing facilities, which would significantly impact our ability to develop, obtain regulatory approval for or market our drug candidates, if approved. Our failure, or the failure of our third-party manufacturers, to comply with applicable regulations could result in sanctions being imposed on us, including clinical holds, fines, injunctions, civil penalties, delays, suspension or withdrawal of approvals, seizures or recalls, operating restrictions and criminal prosecutions, any of which could significantly and adversely affect our financial position.

Our or a third party’s failure to execute on our manufacturing requirements on commercially reasonable terms and in compliance with GMP or other regulatory requirements could adversely affect our business in a number of ways, including:

In addition, we do not have any long-term commitments or supply agreements with any third-party manufacturers. We may be unable to establish any long-term supply agreements with third-party manufacturers or to do so on acceptable terms, which increases the risk of failing to timely obtain sufficient quantities of our drug candidates or such quantities at an acceptable cost. Any performance failure on the part of our existing or future manufacturers or suppliers could delay clinical development or marketing approval, and any related remedial measures may be costly or time consuming to implement. We do not currently have second source for all required raw materials used in the manufacture of our drug candidates. If our existing or future third-party manufacturers cannot perform as agreed, we may be required to replace such manufacturers and we may be unable to replace them on a timely basis or at all, which would have a material adverse impact on our financial position.

We rely on third parties to conduct our preclinical studies and clinical trials. If these third parties do not successfully carry out their contractual duties or meet expected deadlines, we may not be able to obtain regulatory approval for or commercialize our drug candidates and our business could be substantially harmed.

We are dependent on third parties to conduct our clinical trials and preclinical studies. Specifically, we rely on, and will continue to rely on, medical institutions, clinical investigators, CROs and consultants to conduct preclinical studies and clinical trials, in each case in accordance with trial protocols and regulatory requirements.

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These CROs, investigators and other third parties play a significant role in the conduct and timing of these trials and subsequent collection and analysis of data. Though we expect to carefully manage our relationships with such CROs, investigators and other third parties, there can be no assurance that we will not encounter challenges or delays in the future, or that these delays or challenges will not have a material adverse impact on our business, financial condition and prospects. Further, while we have and will have agreements governing the activities of our third-party contractors, we have limited influence over their actual performance. Nevertheless, we are responsible for ensuring that each of our clinical trials is conducted in accordance with the applicable protocol and legal, regulatory and scientific standards and requirements, and our reliance on our CROs and other third parties does not relieve us of our regulatory responsibilities.

In addition, we and our CROs are required to comply with stringent standards governing the conduct of preclinical studies and clinical trials, including Good Laboratory Practice (“GLP”) and GCP requirements, which are regulations and guidelines enforced by the FDA and comparable foreign regulatory authorities, for our drug candidates in clinical development. Regulatory authorities enforce GCPs through periodic inspections of trial sponsors, principal investigators and trial sites. If we or any of our CROs or trial sites fail to comply with applicable GLP, GCP or other requirements, the data generated in our clinical trials may be deemed unreliable, and the FDA or comparable foreign regulatory authorities may require us to perform additional clinical trials before approving our marketing applications, if ever. Furthermore, our clinical trials must be conducted with materials manufactured in accordance with GMP regulations. Failure to comply with these regulations may require us to repeat clinical trials, which would delay the regulatory approval process.

There is no guarantee that any of our CROs, investigators or other third parties will devote adequate time and resources to such trials or studies or perform as contractually required. If any of these third parties fails to meet expected deadlines, adhere to our clinical protocols or meet regulatory requirements, or otherwise perform in a substandard manner, our clinical trials may be extended, delayed or terminated. In addition, many of the third parties with whom we contract may also have relationships with other commercial entities, including our competitors, for whom they may also be conducting clinical trials or other activities that could harm our competitive position. In addition, principal investigators for our clinical trials may be asked to serve as scientific advisors or consultants to us from time to time and may receive cash or equity compensation in connection with such services. If these relationships and any related compensation result in perceived or actual conflicts of interest, or the FDA concludes that the financial relationship may have affected the interpretation of the study, the integrity of the data generated at the applicable clinical trial site may be questioned and the utility of the clinical trial itself may be jeopardized, which could result in the delay or rejection by the FDA of any NDA we submit. Any such delay or rejection could prevent us from commercializing our drug candidates.

In addition, our CROs have the right to terminate their agreements with us in the event of an uncured material breach and under other specified circumstances. If any of our relationships with these third parties terminate, we may not be able to enter into arrangements with alternative third parties on commercially reasonable terms or at all. Switching or adding additional CROs, investigators and other third parties involves additional cost and requires our management’s time and focus. In addition, there is a natural transition period when a new CRO commences work. As a result, delays occur, which can materially impact our ability to meet our desired clinical development timelines. Though we work to carefully manage our relationships with our CROs, investigators and other third parties, there can be no assurance that we will not encounter challenges or delays in the future or that these delays or challenges will not have a material adverse impact on our business, financial condition and prospects.

If any of our relationships with these third parties terminate, we may not be able to enter into arrangements with alternative third parties on commercially reasonable terms or at all. Switching or adding additional CROs, investigators and other third parties involves additional cost and requires our management’s time and focus. In addition, there is a natural transition period when a new CRO commences work. As a result, delays occur, which can materially impact our ability to meet our desired clinical development timelines. Though we work to carefully manage our relationships with our CROs, investigators and other third parties, there can be no

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assurance that we will not encounter challenges or delays in the future or that these delays or challenges will not have a material adverse impact on our business, financial condition and prospects.

Our future success depends on our ability to retain our key executives and to attract, retain and motivate qualified personnel.

We are highly dependent on our management, scientific and medical personnel whose services are critical to our success. Our success depends greatly on the involvement and expertise of our senior executives and qualified scientific staff. While Dr. Philippe Pouletty, MD, our founder and Chairman of our Board since our inception in 2013, resigned from his Chairman position in August 2022, he continues to support our development as a member of our Board as the representative for Truffle Capital. We do not maintain key person insurance. The temporary or permanent unavailability of our management and scientific staff, as well as Dr. Pouletty, could lead to:

Recruiting and retaining additional qualified management and scientific, clinical, manufacturing and sales and marketing personnel will also be critical to our success, particularly as we expand in order to acquire additional skills, such as manufacturing, quality assurance and regulatory and medical affairs. The loss of the services of our senior management team or other key employees could impede the achievement of our research, development and commercialization objectives and seriously harm our ability to successfully implement our business strategy. Furthermore, replacing executive officers and key employees may be difficult and may take an extended period of time because of the limited number of individuals in our industry with the breadth of skills and experience required to successfully develop, gain regulatory approval of and commercialize drug candidates. Competition to hire from this limited pool is intense, and we may be unable to hire, train, retain or motivate these key personnel on acceptable terms given the competition among numerous pharmaceutical and biotechnology companies for similar personnel.

We also experience intense competition for the hiring of scientific and clinical personnel from other companies, universities and research institutions. We may not be able to attract or retain qualified management and scientific personnel in the future due to intense competition for a limited number of qualified personnel. Many of those that compete with us for qualified personnel have greater financial and other resources, different risk profiles and a longer history in the industry than we do. Our competitors may also provide more diverse opportunities and better chances for career advancement. An inability to attract and retain high quality personnel will have a material adverse effect on our business, prospects, financial condition, cash flow or results of operations.

In addition, we rely on consultants and advisors, including scientific and clinical advisors, to assist us in formulating our research and development and commercialization strategy. Our consultants and advisors may be employed by employers other than us and may have commitments under consulting or advisory contracts with other entities that may limit their availability to us. If we are unable to continue to attract and retain high quality personnel, the marketing and production of our drugs could be delayed or prevented, which could, in turn, have a material adverse effect on our business, prospects, financial condition, cash flows or results of operations.

Our employees, principal investigators, consultants and commercial partners may engage in misconduct or other improper activities, including noncompliance with regulatory standards and requirements and insider trading.

We are exposed to the risk of fraud or other misconduct by our employees, principal investigators, consultants and commercial partners. Misconduct by these parties could include intentional failures, reckless and/

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or negligent conduct or unauthorized activity that violates (i) the laws and regulations of the European Economic Area (“EEA”) countries, the European Commission, FDA and other regulatory authorities, including those laws requiring the reporting of true, complete and accurate information to such authorities, (ii) manufacturing standards, (iii) federal and state data privacy, security, fraud and abuse and other healthcare laws and regulations in Europe, the United States and elsewhere and (iv) laws that require the true, complete and accurate reporting of financial information or data. In particular, sales, marketing and business arrangements in the healthcare industry are subject to extensive laws and regulations intended to prevent fraud, misconduct, kickbacks, self-dealing and other abusive practices. These laws and regulations restrict or prohibit a wide range of pricing, discounting, marketing and promotion, sales commission, customer incentive programs and other business arrangements. Such misconduct also could involve the improper use of individually identifiable information, including, without limitation, information obtained in the course of clinical trials, creating fraudulent data in our preclinical studies or clinical trials or illegal misappropriation of drug product, which could result in regulatory sanctions and cause serious harm to our reputation. It is not always possible to identify and deter misconduct by employees and other third parties, and the precautions we take to detect and prevent this activity may not be effective in controlling unknown or unmanaged risks or losses or in protecting us from government investigations or other actions or lawsuits stemming from a failure to comply with these laws or regulations. Additionally, we are subject to the risk that a person or government could allege such fraud or other misconduct, even if none occurred. If any such actions are instituted against us and we are not successful in defending ourselves or asserting our rights, those actions could result in significant civil, criminal and administrative penalties, damages, fines, disgorgement, imprisonment, exclusion from participating in government-funded healthcare programs, such as Medicare and Medicaid, additional reporting requirements and oversight if we become subject to a corporate integrity agreement or similar agreement to resolve allegations of noncompliance with these laws, contractual damages, reputational harm and the curtailment or restructuring of our operations, any of which could have a negative impact on our business, financial condition, results of operations and prospects.

We have limited infrastructure in market access, sales, marketing and distribution.

We lack infrastructure and resources in the fields of sales, marketing and distribution. We need to develop our own marketing and sales capacity, either alone or with partners once marketing authorizations have been obtained. As part of setting up our sales and marketing infrastructure, we will need to incur additional expenses, mobilize management resources, implement new skills and take the time necessary to set up the appropriate organization and structure to support the products in accordance with current legislation and, more generally, optimize commercialization efforts. We compete with many companies that currently have extensive, experienced and well-funded market access, marketing and sales operations to recruit, hire, train and retain marketing and sales personnel, and will have to compete with those companies to recruit, hire, train and retain any of our own market access, marketing and sales personnel. If we are unable to expand our sales and marketing team, we may be unable to compete successfully against these more established companies. Alternatively, if we choose to collaborate, either globally or on a territory-by-territory basis, with third parties that have direct sales forces and established distribution systems, either to augment our own sales force and distribution systems or in lieu of our own sales force and distribution systems, we will be required to negotiate and enter into arrangements with such third parties relating to the proposed collaboration. If we are unable to enter into such arrangements when needed, on acceptable terms, or at all, we may not be able to successfully commercialize any of our drug candidates that receive regulatory approval or any such commercialization may experience delays or limitations. Factors that may inhibit our efforts to build a sales, marketing and distribution organization:

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There are numerous competitors in the market for therapeutic treatments of inflammatory diseases.

The biotechnology and pharmaceutical industries are highly competitive and subject to significant and rapid technological change as researchers learn more about diseases and develop new technologies and treatments. Many pharmaceutical companies, biotech companies, institutions, universities and other research organizations are actively engaged in the research, discovery, development and commercialization of therapeutic responses for the treatment of the diseases targeted by us. Significant competitive factors in our industry include: (i) product efficacy and safety; (ii) quality and breadth of an organization’s technology; (iii) skill of an organization’s employees and its ability to recruit and retain key employees; (iv) timing and scope of regulatory approvals; (v) government reimbursement rates for, and the average selling price of, pharmaceutical products; (vi) the availability of raw materials and qualified manufacturing capacity; (vii) manufacturing costs; (viii) intellectual property and patent rights and their protection; and (ix) sales and marketing capabilities. Given the intense competition in our industry, we cannot assure you that any of the products that we successfully develop will be clinically superior or scientifically preferable to products developed or introduced by our competitors. In addition, significant delays in the development of our drug candidates could allow our competitors to succeed in obtaining European Commission, FDA, PMDA or other regulatory approvals for their drug candidates more rapidly than us, which could place us at a significant competitive disadvantage or deny us marketing exclusivity rights.

Our competitors in the chronic inflammatory disease field are primarily large pharmaceuticals companies including, but not limited to AbbVie, Pfizer, Eli Lilly, Takeda and Johnson & Johnson. Several lines of research are being developed to improve the treatment of IBD. Many companies are working to develop new, more effective and better tolerated treatments with more practical formulations, especially small molecules administered orally, better accepted than monoclonal antibodies that require administration by injection. See “Business—Competition.”

Further, our competitors may be more effective at using their technologies to develop commercial products. Many of the organizations competing with us have significantly greater financial resources and expertise in research and development, manufacturing, preclinical studies, conducting clinical trials, obtaining regulatory approvals and marketing. Mergers and acquisitions in the pharmaceutical and biotechnology industries may result in even more resources being concentrated among a smaller number of our competitors. Smaller or early-stage companies may also prove to be significant competitors, particularly through partnership arrangements with large and established companies. These companies also compete with us in recruiting and retaining qualified scientific and management personnel and establishing clinical trial sites and patient registration for clinical trials, as well as in acquiring technologies complementary to, or necessary for, our programs.

The development potential in the markets in which we operate is such that the arrival of new competition is probable. New market entrants, increased competition in specific areas, or in general, would have a material adverse effect on our business, income, financial position and outlook for growth.

We depend on, and will continue to depend on, collaboration and strategic alliances with third partners. To the extent we are able to enter into collaborative arrangements or strategic alliances, we will be exposed to risks related to those collaborations and alliances.

An important element of our strategy for developing, manufacturing and commercializing our drug candidates is entering into partnerships and strategic alliances with other pharmaceutical companies or other

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industry participants. The collaboration agreements that we have established, and any collaboration arrangements that we may enter into in the future, may not be successful, which would have a negative impact on our business, results of operations, financial condition and growth prospects.

Any partnerships or alliance we have or may have in the future may be terminated for reasons beyond our control or we may not be able to negotiate future alliances on acceptable terms, if at all. These arrangements may result in us receiving less revenue than if we sold our products directly, may place the development, sales and marketing of our products outside of our control, may require us to relinquish important rights or may otherwise be on unfavorable terms. Collaborative arrangements or strategic alliances will also subject us to a number of risks, including the risk that:

Our partnerships and licensing agreements relating to the technologies belonging to us may not be successful.

The various drug candidates developed by us arise from proprietary or licensed technologies with leading academic partners, including Scripps Research Institute, University of Chicago, Brigham Young University, the Montpellier Institute of Molecular Genetics at the Centre National de la Recherche Scientifique (“CNRS”) and the Institut Curie. If the clinical trials conducted by us were to reveal safety and/or therapeutic efficacy problems or if the use of one of the platforms were to violate an intellectual property right held by a third party, this could threaten the use and operation of some of our technology platforms and require additional research and development efforts and additional time and expense to address these difficulties, with success not being guaranteed. The development of a portion of our product portfolio would be affected, which would have a material adverse effect on our business, outlook, growth, financial position and income.

The reimbursement of drugs and treatments is beyond our control.

After achieving regulatory authorization and once marketing authorization is granted, the process of setting the sales price of drugs and their reimbursement rates begins. The conditions for setting the sales price and reimbursement rate for drugs are beyond the control of pharmaceutical companies. They are decided by competent public committees and bodies and by social security or private insurance companies. In this context, we or our partners could be asked to perform additional studies on our products. These studies could generate additional costs for us or our partners and lead to delays in marketing the drug, which could have an impact on our financial position.

There is significant uncertainty related to the reimbursement of newly-approved drugs. The level of reimbursement will impact market acceptance and sale of our drug candidates. Reimbursement by a third-party is

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dependent on a number of factors, including, without limitation, the third-party payor’s determination that use of a product is:

The possibility that we could receive royalties from our industrial partner or partners on the sale of some of our products and our ability to make sufficient profits on the marketing of our treatments or those for which we have entered into distribution contracts will depend on these reimbursement conditions. If delays in the price negotiation procedure result in a significant delay in marketing, if our product does not obtain an appropriate level of reimbursement, or if the accepted price level and reimbursement rate of the treatments we market are changed, our profitability will be reduced.

We are also unable to guarantee that we will succeed in maintaining, over time, the price level of our products or those for which licenses have been granted, or the accepted reimbursement rate. Under these conditions, there could be a material adverse effect on our business, financial position and results of operations.

The pricing, insurance coverage and reimbursement status of newly-approved products is uncertain. Failure to obtain or maintain adequate coverage and reimbursement for our drug candidates, if approved, could limit our ability to market those products and decrease our ability to generate product revenue.

Successful sales of our drug candidates, if approved, depend on the availability of coverage and adequate reimbursement from third-party payors including governmental healthcare programs, such as Medicare and Medicaid in the United States, managed care organizations and commercial payors, among others. Significant uncertainty exists as to the coverage and reimbursement status of any drug candidates for which we obtain regulatory approval.

In the United States, no uniform policy for coverage and reimbursement exists, and coverage and reimbursement for drug products can differ significantly from payor to payor. Therefore, one payor’s determination to provide coverage for a drug product does not assure that other payors will also provide coverage for the drug product. Third-party payors often follow Medicare coverage policy and payment limitations in setting their own reimbursement rates, but also have their own methods and approval process apart from Medicare determinations. As a result, the coverage determination process is often a time-consuming and costly process that will require us to provide scientific and clinical support for the use of our products to each payor separately, with no assurance that coverage and adequate reimbursement will be applied consistently or obtained in the first instance. Moreover, coverage policies and third-party reimbursement rates may change at any time. Even if favorable coverage and reimbursement status is attained for one or more products for which we receive regulatory approval, less favorable coverage policies and reimbursement rates may be implemented in the future.

Reimbursement may impact the demand for, and/or the price of, any product for which we obtain marketing approval. Assuming we obtain coverage for a given product by a third-party payor, the resulting reimbursement payment rates may not be adequate or may require co-payments that patients find unacceptably high. Patients who are prescribed medications for the treatment of their conditions, and their prescribing physicians, generally rely on third-party payors to reimburse all or part of the costs associated with their prescription drugs. Patients are unlikely to use our products unless coverage is provided, and reimbursement is adequate to cover all or a significant portion of the cost of our products. Therefore, coverage and adequate reimbursement is critical to new product acceptance.

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Additionally, we or our collaborators may develop companion diagnostic tests for use with our drug candidates. We or our collaborators will be required to obtain coverage and reimbursement for these tests separate and apart from the coverage and reimbursement we seek for our drug candidates, once approved. Similar challenges to obtaining coverage and reimbursement, applicable to pharmaceutical or biological products, will apply to companion diagnostics. Our inability to promptly obtain coverage and adequate reimbursement from both third-party payors for the drug candidates and companion diagnostic tests that we or our collaborators develop and for which we obtain regulatory approval could have a material and adverse effect on our business, financial condition, results of operations and prospects.

In the EU, pricing and reimbursement schemes vary widely from country to country. Some countries provide that products may be marketed only after a reimbursement price has been agreed. Some countries may require the completion of additional studies that compare the cost-effectiveness of a particular drug candidate to currently available therapies. EU member states may approve a specific price for a product or it may instead adopt a system of direct or indirect controls on the profitability of the company placing the product on the market. Other member states allow companies to fix their own prices for products, but monitor and control company profits. The downward pressure on health care costs has become intense. As a result, increasingly high barriers are being erected to the entry of new products. In addition, in some countries, cross-border imports from low-priced markets exert competitive pressure that may reduce pricing within a country. Any country that has price controls or reimbursement limitations may not allow favorable reimbursement and pricing arrangements, and prices are usually revised periodically, such that any given price may decrease upon various occurrences.

Additionally, the containment of healthcare costs has become a priority of federal and state governments, and the prices of drugs have been a focus of this effort. The U.S. government, state legislatures and foreign governments have shown significant interest in implementing cost-containment programs, including price controls, restrictions on reimbursement and requirements for substitution of generic products. Adoption of price controls and cost-containment measures, and adoption of more restrictive policies in jurisdictions with existing controls and measures, could further limit our net revenue and results.

Price controls may be imposed in markets in which we operate, which may negatively affect our future profitability.

In some countries, particularly EU member states, Japan, Australia and Canada, the pricing of prescription drugs is subject to governmental control. In these countries, pricing negotiations with governmental authorities can take considerable time after receipt of marketing approval for a product. In addition, there can be considerable pressure by governments and other stakeholders on prices and reimbursement levels, including as part of cost containment measures. Political, economic and regulatory developments may further complicate pricing negotiations, and pricing negotiations may continue after reimbursement has been obtained. Reference pricing used by various EU member states and parallel distribution, or arbitrage between low-priced and high-priced member states, can further reduce prices. In some countries, we or our collaborators may be required to conduct a clinical trial or other studies that compare the cost-effectiveness of our drug candidates to other available therapies in order to obtain or maintain reimbursement or pricing approval. Publication of discounts by third-party payors or authorities may lead to further pressure on the prices or reimbursement levels within the country of publication and other countries. If reimbursement of our drug candidates is unavailable or limited in scope or amount, or if pricing is set at unsatisfactory levels, there could be a material adverse effect on our business, financial condition or results of operations.

The COVID-19 pandemic has been highly disruptive to our business, industry and in general. An outbreak of other communicable diseases around the world may cause further disruption.

Any public health outbreak may cause any of the following:

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In addition to the risks listed above, and as part of our clinical trials in countries in pandemic zones, we may also experience the following adverse effects:

If one or more of the above risks were to materialize, the planned and ongoing clinical trials and, therefore, the publication of the data and results of these studies and all subsequent steps leading to the commercialization of drug candidates being studied, could be significantly delayed. Such a situation could have a material adverse effect on our business, income, financial position and growth.

The extent to which the outbreak of communicable diseases around the world may impact our activity and clinical trials will depend on future developments, which cannot be predicted with certainty, such as the emergence of diseases that may be resistant to the vaccines or treatments currently available, access to vaccines and treatments for the various populations worldwide, the final geographical spread of the disease, its duration, travel restrictions and social distancing measures in the European Union, the United States and other countries, business closures or disruptions, and the effectiveness of measures taken in those countries to contain and treat the disease. There can be no assurance that the outbreak of communicable diseases around the world will not result in an adverse effect on financial markets, our share price and our ability to obtain finance.

The war between Ukraine and Russia may affect our business, industry and the markets in which we operate.

In February 2022, Russia invaded Ukraine. The conflict has already had major implications for the global economy and the rate of inflation, particularly in relation to the supply of energy, raw materials and food products. It has also caused intense volatility on the financial markets, something that is still ongoing at the reporting date and has pushed down stock market prices around the world.

Given these developments, we have decided not to include Russia and Belarus in our global Phase 3 program for obefazimod in UC. However, the global scale of this conflict cannot be predicted at this stage. We, therefore, cannot rule out an adverse impact of this conflict on our business, including in terms of access to raw materials, logistics, the performance of clinical trials and in relation to any future financing we may seek.

The Phase 2b maintenance trial of obefazimod in moderately to severely active UC is our only clinical trial currently in progress in Ukraine. We have, however, terminated a few trial sites since the Russia/Ukraine war

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began. The 12-month assessment was carried out in all the Ukrainian patients before the war broke out and these patients are therefore included in the one-year maintenance results that were reported on April 6, 2022. Ukrainian patients who completed the two-year Phase 2b maintenance trial have been transitioned to the long-term safety and efficacy trial that is still on-going. None of these sites are located in the Crimea Region of Ukraine, the so-called Donetsk People’s Republic, or the so-called Luhansk People’s Republic. We are also evaluating the possibility to include a few Ukrainian sites in the western part of Ukraine in the ABTECT Phase 3 clinical trials.

Risks Related to Intellectual Property

Our ability to exclusively commercialize our drug candidates may decrease if we are unable to protect our intellectual property rights or if these rights are insufficient for our purposes.

Our commercial success depends in part on our ability and the ability of our partners to obtain, maintain and ensure, against third parties, the protection of our patents, trademarks and related applications and other intellectual property rights or similar rights (such as trade secrets, business secrets and know-how) or those we are authorized to use in the course of our business in Europe, the United States, Asia and other key countries. We dedicate substantial financial and human resources to this and intend to continue our policy of protection through new patent applications as soon as we deem it appropriate.

Our technology is currently protected by patents and patent applications that we have filed or for which we have an exclusive license. However, we or our partners might not be able to maintain the protection of our intellectual property rights and we could, thereby, lose our technological and competitive advantage in whole or in part.

Firstly, our intellectual property rights and those of our partners offer protection for a period that may vary from one territory to another. The term of individual patents depends upon the legal term of the patents in the countries in which they are obtained. In most countries in which we have obtained or are seeking patent protection for our drug candidates, the patent term is 20 years from the earliest filing date of a non-provisional patent application. In the United States, the term of a patent may be lengthened by a patent term adjustment, which provides for term extension in the case of administrative delays at the United States Patent and Trademark Office (“USPTO”) in granting a patent, or may be shortened if a patent is terminally disclaimed over another patent with an earlier expiration date. Furthermore, in the United States, the term of a patent covering an FDA approved drug may be eligible for a patent term extension under the Hatch-Waxman Amendments as compensation for the loss of patent term during the FDA regulatory review process. The period of extension may be up to five years beyond the expiration of the patent but cannot extend the term of a patent beyond a total of 14 years from the date of product approval. Only one patent covering a single FDA-approved product among those eligible for an extension may be extended. In the future, if any of our drug candidates receives FDA approval, we expect to apply for a patent term extension, if available, to extend the term of the patent covering such approved drug product. In France and the rest of Europe generally, the term of a patent is 20 years from the date the patent application is filed, with the understanding that this period may be extended up to another five years if a supplementary protection certificate is filed and an additional six months if a pediatric investigation plan is applied. We expect to seek patent term extensions in any jurisdictions where they are available, however, there is no guarantee that the applicable authorities, including the FDA, will agree with our assessment of whether such an extension should be granted, and even if granted, the length of such an extension.

Secondly, we and our partners could encounter difficulties in the filing or examination of some of our patent, trademark or other intellectual property rights applications currently being examined/registered. During the patent application process, we may receive Office Actions from the USPTO or from comparable agencies in foreign jurisdictions rejecting the claims of the patent application. Although we would be given an opportunity to respond to those objections, we may be unable to overcome such rejections. At the time a patent application is filed, there may be other patents that could constitute opposable prior art that may have not yet been published. Despite prior art searches and monitoring, we cannot be certain that we are the first to conceive of an invention

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and file a patent application relating thereto; in particular, it should be noted that in most countries, the publication of patent applications takes place 18 months after the earliest priority date of patent filing, or in some cases not at all, and that discoveries are sometimes only the subject of publication or patent application months or even years later. Likewise, when filing one of our trademarks in a country where it is not covered, we could find that the trademark in question is not available in that country. A new trademark would then need to be sought for the country in question or an agreement negotiated with the prior holder of the trademark. We may not be able to prevent a disclosure of information to third parties that could have an impact on our future intellectual property rights. Therefore, it is in no way certain that our current and future applications for patents, trademarks and other intellectual property rights will result in registrations.

Thirdly, the simple granting or registration of a patent, trademark or other intellectual property right does not guarantee validity or enforceability. Our competitors may at any time contest the validity or enforceability of our or our partners’ patents, trademarks or applications relating thereto before a court or in the context of other specific procedures which, depending on the outcome of such disputes, could reduce their scope, result in their invalidation or allow them to be circumvented by competitors. In addition, developments, changes or divergences in the interpretation of the legal framework governing intellectual property in Europe, the United States or other countries could allow competitors to use our or our partners’ inventions or intellectual property rights to develop or market our products or technologies without financial compensation. Moreover, there are still certain countries that do not protect intellectual property rights in the same way as in Europe and the United States, and the effective procedures and rules necessary to ensure the defense of our rights may not exist in these countries. There is therefore no certainty that our existing and future patents, trademarks and other intellectual property rights will not be disputed, invalidated or circumvented, or that they will provide effective protection against competition.

Consequently, our rights to our owned or licensed patents, trademarks and related applications and other intellectual property rights may not confer the protection expected against competition. We therefore cannot guarantee with certainty that:

Were these eventualities to occur, they could have a material adverse effect on our business and growth.

In addition, third parties (or even our employees) could use or attempt to use elements of our technologies protected by an intellectual property right, which would create a detrimental situation for us. We may therefore be compelled to bring legal or administrative proceedings against these third parties in order to enforce our intellectual property rights (patents, trademarks, designs and models or domain names) in court.

Enforcing a claim that a party illegally infringed or misappropriated our intellectual property is difficult, expensive and time-consuming, and the outcome is unpredictable. Any litigation or dispute, regardless of the outcome, could lead to substantial costs, affect our reputation, negatively influence our income and financial position and possibly not lead to the desired protection or sanction. Some competitors with more substantial resources than us may be able to bear the costs of litigation more easily.

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If we fail to comply with our obligations in any agreements under which we may license intellectual property rights from third parties or otherwise experience disruptions to our business relationships with our licensors, we could lose rights that are important to our business.

Our ability to pursue the development of some of our drug-based candidates depends on the maintenance in force of the licensing agreements entered into with various institutes. We have licenses granted by the CNRS, the University of Montpellier and/or the Institut Curie for certain patents or patent co-ownership rights resulting from cooperation with the CNRS, the University of Montpellier and the Institut Curie, which allowed obefazimod to be developed and a chemical library of more than 2,200 small molecules to be generated.

These license contracts provide the possibility for the licensor to end an agreed exclusivity or terminate the contracts in certain events, including the event of non-payment of fees, a dispute over the validity of the patents licensed or a violation by us of our obligations.

We may from time to time be party to license or collaboration agreements with third parties to advance our research or allow commercialization of current or future drug candidates. Such agreements may impose numerous obligations, such as development, diligence, payment, commercialization, funding, milestone, royalty, sublicensing, insurance, patent prosecution, enforcement and other obligations on us and may require us to meet development timelines, or to exercise commercially reasonable efforts to develop and commercialize licensed products, in order to maintain the licenses. In spite of our best efforts, our licensors might conclude that we have materially breached our license agreements and might therefore terminate the license agreements, thereby removing or limiting our ability to develop and commercialize products and technologies covered by these license agreements.

Any termination of these licenses, or if the underlying licensed rights fail to provide the intended exclusivity, could result in the loss of significant rights and could harm our ability to commercialize our current or future drug candidates, and competitors or other third parties would have the freedom to seek regulatory approval of, and to market, products identical to ours and we may be required to cease our development and commercialization of certain of our current or future drug candidates. Any of the foregoing could have a material adverse effect on our competitive position, business, financial conditions, results of operations, and prospects.

Disputes may also arise between us and our licensors regarding intellectual property subject to a license agreement, including:

In addition, the agreements under which we may license intellectual property or technology from third parties are likely to be complex, and certain provisions in such agreements may be susceptible to multiple interpretations. The adverse resolution of any contract interpretation disagreement that may arise could narrow what we believe to be the scope of our rights to the relevant intellectual property or technology or increase what

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we believe to be our financial or other obligations under the relevant agreement, either of which could have a material adverse effect on our business, financial condition, results of operations and prospects. Moreover, if disputes over intellectual property that we have licensed or may license prevent or impair our ability to maintain future licensing arrangements on acceptable terms, we may be unable to successfully develop and commercialize the affected current or future drug candidates, which could have a material adverse effect on our business, financial conditions, results of operations and prospects.

We may be sued for infringing or misappropriating the intellectual property rights of third parties, and if we are, such litigation could be costly and time consuming and could prevent or delay us from developing or commercializing our drug candidates.

Our commercial success will also depend on our ability to develop products and technologies that do not infringe the patents or other rights of third parties. It is important for the success of our business that we are able to use our products and conduct research and development efforts leading to commercialization of our products without infringing patents or other third-party rights.

We continue to carry out, as we have done to date, the preliminary studies that we consider necessary in view of the above risks, before investing in the development of our various products and technologies. With the help of intellectual property consulting and law firms, we monitor our competitors’ activity (particularly with respect to patent filings).

We therefore cannot guarantee with certainty that:

In the event of intellectual property litigation, we may have to:

Litigation can also result in an order to pay damages (including treble damages) and being subject to injunctions.

Patent terms may be inadequate to protect our competitive position on our drugs for an adequate amount of time, and we may seek to rely, but may not be able to rely, on other forms of protection, such as regulatory exclusivity.

Given the amount of time required for the development, testing and regulatory review of new drug candidates, patents protecting such candidates might expire before or shortly after such candidates are

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commercialized. For example, the certain patents protecting obefazimod’s composition of matter expire in 2030 and the certain patents protecting obefazimod methods of use expire in 2035 which pose a risk to its successful commercialization. We expect to seek extensions of patent terms in the United States and, if available, in other countries where we are prosecuting patents. In the United States, the Drug Price Competition and Patent Term Restoration Act of 1984 permits a patent term extension of up to five years beyond the normal expiration of the patent, which is limited to the approved indication (or any additional indications approved during the period of extension). However, the applicable authorities, including the FDA and the USPTO in the United States, and any equivalent regulatory authority in other countries, may not agree with our assessment of whether such extensions are available, and may refuse to grant extensions to our patents, or may grant more limited extensions than we request. We may also seek to rely on other forms of protection, such as regulatory exclusivity, but there can be no assurance that such other forms of protection will be available or sufficient.

We will not seek to protect our intellectual property rights in all jurisdictions throughout the world and we may not be able to adequately enforce our intellectual property rights even in the jurisdictions where we seek protection.

Filing, prosecuting and defending patents on our drug candidates in all countries and jurisdictions throughout the world would be prohibitively expensive, and our intellectual property rights in some countries outside the United States could be less extensive than those in the United States, assuming that rights are obtained in the United States. Competitors may use our technologies in jurisdictions where we do not pursue and obtain patent protection to develop their own products and further, may export otherwise infringing products to territories where we have patent protection, but enforcement is not as strong as that in the United States. These products may compete with our drugs and our patents or other intellectual property rights may not be effective or sufficient to prevent them from competing. Even if we pursue and obtain issued patents in particular jurisdictions, our patent claims or other intellectual property rights may not be effective or sufficient to prevent third parties from so competing.

In addition, the laws of some foreign countries do not protect intellectual property rights to the same extent as the federal and state laws in the United States. Many companies have encountered significant problems in protecting and defending intellectual property rights in certain foreign jurisdictions. The legal systems of some countries, particularly developing countries, do not favor the enforcement of patents and other intellectual property protection, especially those relating to biopharmaceuticals or biotechnologies. This could make it difficult for us to stop the infringement of our patents, if obtained, or the misappropriation of our other intellectual property rights. For example, many foreign countries have compulsory licensing laws under which a patent owner must grant licenses to third parties. In addition, many countries limit the enforceability of patents against third parties, including government agencies or government contractors. In these countries, patents may provide limited or no benefit. Patent protection must ultimately be sought on a country-by-country basis, which is an expensive and time-consuming process with uncertain outcomes. Accordingly, we may choose not to seek patent protection in certain countries, and we will not have the benefit of patent protection in such countries.

Proceedings to enforce our patent rights in foreign jurisdictions could result in substantial costs and divert our efforts and attention from other aspects of our business, could put our patents at risk of being invalidated or interpreted narrowly, could put our patent applications at risk of not being issued and could provoke third parties to assert claims against us. We may not prevail in any lawsuits that we initiate and the damages or other remedies awarded, if any, may not be commercially meaningful. In addition, changes in the law and legal decisions by courts in the United States and foreign countries may affect our ability to obtain adequate protection for our technology and the enforcement of our intellectual property. In addition, monitoring the unauthorized use of our products and technology and the infringement of our intellectual property rights is challenging. We cannot guarantee with certainty that we will be able to prevent, take legal action against and obtain compensation for infringement, misappropriation or unauthorized use of our products and technologies, particularly in foreign countries where our rights are less well protected because of the territorial scope of intellectual property rights. Accordingly, our efforts to enforce our intellectual property rights around the world may be inadequate to obtain a significant commercial advantage from the intellectual property that we develop or license.

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Further, in Europe, a new unitary patent system took effect June 1, 2023, which significantly impacts European patents, including those granted before the introduction of such a system. Under the unitary patent system, European applications have the option, upon grant of a patent, of becoming a Unitary Patent which will be subject to the jurisdiction of the Unitary Patent Court, or the UPC. As the UPC is a new court system, there is no precedent for the court, increasing the uncertainty of any litigation. Patents granted before the implementation of the UPC will have the option of opting out of the jurisdiction of the UPC and remaining as national patents in the UPC countries. Patents that remain under the jurisdiction of the UPC will be potentially vulnerable to a single UPC-based revocation challenge that, if successful, could invalidate the patent in all countries who are signatories to the UPC. We cannot predict with certainty the long-term effects of any potential changes.

In addition, geo-political actions in the United States and in foreign countries could increase the uncertainties and costs surrounding the prosecution or maintenance of our patent applications and the maintenance, enforcement or defense of our issued patents. For example, the United States and foreign government actions related to Russia’s invasion of Ukraine may limit or prevent filing, prosecution, and maintenance of patent applications in Russia. Government actions may also prevent maintenance of issued patents in Russia. These actions could result in abandonment or lapse of our patents or patent applications, resulting in partial or complete loss of patent rights in Russia. If such an event were to occur, it could have a material adverse effect on our business. In addition, a decree was adopted by the Russian government in March 2022, allowing Russian companies and individuals to exploit inventions owned by patentees from the United States without consent or compensation. Consequently, we would not be able to prevent third parties from practicing our inventions in Russia or from selling or importing products made using our inventions in and into Russia. Accordingly, our competitive position may be impaired, and our business, financial condition, results of operations and prospects may be adversely affected.

If our trademarks and trade names are not adequately protected by us or our partners that develop trademarks for our future products, then we may not be able to build name or brand recognition in our markets of interest, and our business may be adversely affected.

Our registered or unregistered trademarks and trade names and the registered or unregistered trademarks and trade names that our partners will develop may be challenged, infringed, diluted, circumvented or declared generic or determined to be infringing on other marks. We and our partners may not be able to protect our rights to these trademarks and trade names, which we need to build name and brand recognition among potential partners or customers in our markets of interest. We expect to rely on our partners to protect the trade names and trademarks that they will develop, and they may not adequately protect such tradenames and trademarks, and we may have little or no recourse in respect thereof. At times, competitors may adopt trademarks and trade names similar to ours, thereby impeding our ability to build brand identity and possibly leading to market confusion. During the trademark registration process, we may receive Office Actions from the USPTO or from comparable agencies in foreign jurisdictions objecting to the registration of our trademark. Although we would be given an opportunity to respond to those objections, we may be unable to overcome such rejections. In addition, in the USPTO and in comparable agencies in many foreign jurisdictions, third parties are given an opportunity to oppose pending trademark applications and/or to seek the cancellation of registered trademarks. Opposition or cancellation proceedings may be filed against our trademark applications or registrations, and our trademark applications or registrations may not survive such proceedings. In addition, there could be potential trademark infringement claims brought by owners of other registered trademarks or trademarks that incorporate variations of our registered or unregistered trademarks. Over the long term, if we are unable to establish name and brand recognition based on our trademarks, then we may not be able to compete effectively and our business may be adversely affected.

Obtaining and maintaining patent protection depends on compliance with various procedural, document submission, fee payment and other requirements imposed by governmental patent agencies, and our patent protection could be reduced or eliminated for non-compliance with these requirements.

Periodic maintenance fees, renewal fees, annuity fees and various other governmental fees on patents and applications are required to be paid to the USPTO and various governmental patent agencies outside of the

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United States in several stages over the lifetime of the patents and applications. The USPTO and various non-U.S. governmental patent agencies require compliance with a number of procedural, documentary, fee payment and other similar provisions during the patent application process and after a patent has issued. There are situations in which non-compliance can result in abandonment or lapse of the patent or patent application, resulting in partial or complete loss of patent rights in the relevant jurisdiction.

If we are unable to protect the confidentiality of our trade secrets and know-how, our business and competitive position could be harmed.

In addition to seeking patent protection for our drug candidates, we also rely on trade secrets, including unpatented know-how, technology and other proprietary information, to establish and maintain our competitive position.

It is also important for us to protect against the unauthorized use and disclosure of our confidential information, know-how and trade secrets. Unpatented and/or unpatentable technologies, processes, methods, know-how and data are considered trade secrets that we seek to protect, in part, by entering into non-disclosure and confidentiality agreements with parties who have access to them, such as our employees, collaborators, consultants, advisors, university and/or institutional researchers and other third parties. We also have entered or seek to enter into confidentiality and invention or patent assignment agreements with our employees, advisors and consultants.

In the context of collaboration, partnership or research contracts, or other types of cooperation between us and researchers from academic institutions, and with other public or private entities, subcontractors, or any co-contracting third parties, various information and/or products may be entrusted to them in order to conduct certain tests and clinical trials. In such cases, we require that confidentiality agreements be signed. Furthermore, as a general rule, we take care that the collaboration or research contracts that we are party to give us access to full ownership or co-ownership of results and/or inventions resulting from the collaboration, or to an exclusive license based on these results and/or inventions resulting from the collaboration.

Despite these efforts, counterparties may breach our agreements and disclose our proprietary information, including our trade secrets, and we may not be able to obtain adequate remedies for such breaches. Our trade secrets may also be obtained by third parties by other means, such as breaches of our physical or computer security systems. Enforcing a claim that a party illegally disclosed or misappropriated a trade secret is difficult, expensive and time-consuming, and the outcome is unpredictable. In addition, some courts inside and outside the United States are less willing or unwilling to protect trade secrets. Moreover, if any of our trade secrets were to be lawfully obtained or independently developed by a competitor, we would have no right to prevent them, or those to whom they communicate it, from using that technology or information to compete with us. If any of our trade secrets were to be disclosed to, or independently developed by, a competitor, our competitive position would be harmed and our business may be adversely affected.

There can be no assurance that the agreements put in place to protect our technology and trade secrets and/or the know-how being used will provide the protection sought or will not be violated, that we will have appropriate solutions for such violations, or that our trade secrets will not be disclosed to or independently developed by our competitors. In the context of contracts that we enter into with third parties, we sometimes take the precaution of providing that they are not authorized to use third-party services or that they may only do so with our prior approval. However, it cannot be ruled out that some of these co-contractors may nevertheless use third parties. In this event, we have no control over the conditions under which third parties with which we do not contract protect their confidential information, irrespective of whether we provide in our agreements with our co-contractors that they undertake to pass on confidentiality obligations to their own co-contractors.

Such contracts therefore expose us to the risk of having the third parties concerned (i) claim the benefit of intellectual property rights on our inventions or other intellectual property rights, (ii) fail to ensure the confidentiality of unpatented innovations or improvements of our confidential information and know-how,

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(iii) disclose our trade secrets to our competitors or independently develop these trade secrets and/or (iv) violate such agreements, without our having an appropriate solution for such violations.

Consequently, our rights to our confidential information, trade secrets and know-how may not confer the expected protection against competition and we cannot guarantee with certainty that:

The occurrence of one or more of these risks could have a material adverse effect on our business, outlook, financial position, income and growth.

We are subject to cyber risks.

We are dependent upon the availability, capacity, reliability and security of our information technology infrastructure to conduct daily operations. We depend on various information technology systems to process and record financial data, research data and confidential information, process clinical data, manage financial resources and communicate with employees and third parties. In particular, we store information about drug candidates, which is critical to our research and development, on our computer systems.

Third parties on which we rely have in the past been affected by cyberattacks and may in the future fail, or are perceived to have failed, to maintain sufficient cyber-security safeguards, which could compromise data they hold on our behalf. If our suppliers or other third parties we collaborate with suffer from cyberattacks or cybersecurity breaches, we could face significant consequences, including but not limited to: government enforcement actions (e.g., investigations, fines, penalties, audits, inspections, and similar); litigation (including class-action claims); additional reporting requirements and/or oversight; bans on processing personal data; and orders to destroy or not use personal data.

Although we maintain industry-standard backups and procedures, we are at risk of financial loss, reputational damage and general disruption from a failure of our information technology infrastructure or an attack for the purposes of espionage, extortion, terrorism or to cause embarrassment. Any failure of, or attack against, our information technology infrastructure may be difficult to prevent or detect, and our internal policies to mitigate these risks may be inadequate or ineffective. We may not be able to recover any losses that may arise from such a failure or attack, which could have a material adverse effect on our business, outlook, financial position, income and growth.

Intellectual property rights do not address all potential threats to our competitive advantage.

The degree of future protection afforded by our intellectual property rights is uncertain because intellectual property rights have limitations, and may not adequately protect our business, or permit us to maintain our competitive advantage. The following examples are illustrative.

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Risks Related to Legal and Compliance

Our business is subject to a restrictive and changing regulatory framework.

One of the major issues for a growing company like ours is to successfully develop, alone or with the help of partners, products incorporating our technologies in an increasingly restrictive regulatory environment. The pharmaceutical industry faces constant changes in its legal and regulatory environment and increased oversight by the competent authorities, such as the National Agency for Medicines and Health Products Safety (“ANSM”) in France, the EMA in the European Union, the FDA in the United States or the PMDA in Japan, and other regulatory authorities in the rest of the world. At the same time, the public is demanding more guarantees regarding drug safety and efficacy. This may at any time lead to a more restrictive regulatory environment for our drug candidates which may have a material adverse effect on business, financial position, income, growth and outlook.

Health authorities oversee research and development, preclinical studies, clinical trials, the regulation of pharmaceutical companies, and drug manufacturing and commercialization. This increasing stringency of the legislative and regulatory framework is common worldwide; however, requirements may vary from country to country. In particular, health authorities, especially the ANSM, EMA, FDA and PMDA, have imposed increasingly burdensome requirements in terms of the volume of data required to demonstrate the efficacy and safety of a product. These increased requirements may have thus reduced the number of products authorized in comparison to the number of applications filed. Products on the market are also subject to regular reassessment of the risk/benefit ratio after their authorization. The delayed discovery of problems not identified at the research stage can lead to marketing restrictions, suspension or withdrawal of the product, and to an increased risk of litigation.

Therefore, the authorization process is long and expensive; it can take many years and the result is not predictable. Insofar as new legal or regulatory provisions would result in an increase in the cost of obtaining and maintaining product marketing authorizations or limit the targeted indications for a product that a product targets or the economic value of a new product to its inventor, the growth prospects for the pharmaceutical industry, and us, could be reduced. If we experience delays completing, or if we terminate, any of our clinical trials, or if we are required to conduct additional clinical trials, the commercial prospects for our drug candidates may be harmed and our ability to generate product revenue will be delayed. The occurrence of one or more of these risks could have a material adverse effect on our business, outlook, financial position, income and growth.

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We are subject to healthcare laws and regulations which may require substantial compliance efforts and could expose us to criminal sanctions, civil and administrative penalties, contractual damages, reputational harm and diminished profits and future earnings, among other penalties.

Healthcare providers, including physicians, and others will play a primary role in the recommendation and prescription of our products, if approved. Our arrangements with such persons and third-party payors and our general business operations will expose us to broadly applicable fraud and abuse and other healthcare laws and regulations that may constrain the business or financial arrangements and relationships through which we research, market, sell and distribute our drugs, if we obtain marketing approval. Restrictions under applicable U.S. federal, state and foreign healthcare laws and regulations include, but are not limited to, the following:

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Ensuring that our business arrangements with third parties comply with applicable healthcare laws and regulations will likely be costly. It cannot be excluded that governmental authorities will conclude that our business practices do not comply with current or future statutes, regulations or case law involving applicable fraud and abuse or other healthcare laws and regulations. If our operations were found to be in violation of any of these laws or any other governmental regulations that may apply to us, we may be subject to significant civil, criminal and administrative penalties, damages, fines, disgorgement, imprisonment, possible exclusion from government funded healthcare programs, such as Medicare and Medicaid, contractual damages, reputational harm, diminished profits and future earnings and curtailment of our operations, any of which could substantially disrupt our operations. If the physicians or other providers or entities with whom we expect to do business are found not to be in compliance with applicable laws, they may be subject to criminal, civil or administrative sanctions, including exclusions from government funded healthcare programs. We may incur significant costs achieving and maintaining compliance with applicable federal and state privacy, security, and fraud laws. Any action against us for violation of these laws, even if we successfully defend against it, could cause us to incur significant legal expenses and divert our management’s attention from the operation of our business.

Current and future health reform measures could adversely affect our business operations.

In the United States and some foreign jurisdictions there have been, and we expect there will continue to be, several legislative and regulatory changes and proposed reforms of the healthcare system to contain costs, improve quality, and expand access to care. For example, in March 2010, President Obama signed the ACA into law, which substantially changed the way healthcare is financed by both governmental and private insurers and continues to significantly impact the United States pharmaceutical industry.

There have been judicial, congressional and executive branch challenges to certain aspects of the ACA. For example, on June 17, 2021, the United States Supreme Court dismissed a challenge on procedural grounds that argued the ACA is unconstitutional in its entirety because the individual mandate was repealed by Congress. Moreover, there have been a number of health reform initiatives by the Biden administration that have impacted the ACA. For example, on August 16, 2022, President Biden signed the Inflation Reduction Act of 2022 (“IRA”), into law, which among other things, extends enhanced subsidies for individuals purchasing health insurance coverage in ACA marketplaces through plan year 2025. The IRA also eliminates the “donut hole” under the Medicare Part D program beginning in 2025 by significantly lowering the beneficiary maximum out-of-pocket cost through a newly-established manufacturer discount program. It is unclear how other healthcare reform measures, if any, will impact our business.

In addition, other legislative changes have been proposed and adopted in the United States since the ACA was enacted. For example, on August 2, 2011, the Budget Control Act of 2011 was signed into law which among other things, led to aggregate reductions in Medicare payments to providers. These reductions went into effect on April 1, 2013, and, due to subsequent legislative amendments, will remain in effect until 2032, with the exception of a temporary suspension from May 1, 2020, through March 31, 2022, due to the COVID-19 pandemic, unless additional Congressional action is taken.

Additionally, there have been several recent U.S. presidential executive orders, congressional inquiries and proposed and enacted legislation at the federal and state levels designed to, among other things, bring more

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transparency to drug pricing, review the relationship between pricing and manufacturer patient programs, reduce the cost of drugs under Medicare, and reform government program reimbursement methodologies for drugs. For example, on March 11, 2023, the American Rescue Plan Act of 2021 was signed into law, which eliminates the statutory Medicaid drug rebate cap, currently set at 100% of a drug’s average manufacturer price, beginning January 1, 2024. In addition, the IRA, among other things, (1) directs HHS to negotiate the price of certain single-source drugs and biologics covered under Medicare and (2) imposes rebates under Medicare Part B and Medicare Part D to penalize price increases that outpace inflation. The IRA permits HHS to implement many of these provisions through guidance, as opposed to regulation, for the initial years. HHS has and will continue to issue and update guidance as these programs are implemented. These provisions took effect progressively starting in fiscal year 2023, although the Medicare drug price negotiation program is currently subject to litigation. It is currently unclear how the IRA will be implemented but is likely to have a significant impact on the pharmaceutical industry. Further, in response to the Biden administration’s October 2022 executive order, on February 14, 2023, HHS released a report outlining three new models for testing by the CMS Innovation Center which will be evaluated on their ability to lower the cost of drugs, promote accessibility and improve quality of care. It is unclear whether the models will be utilized in any health reform measures in the future. We expect that additional U.S. federal healthcare reform measures will be adopted in the future, any of which could limit the amounts that the U.S. federal government will pay for healthcare products and services, which could result in reduced demand for our drug candidates or additional pricing pressures.

At the state level, legislatures have increasingly passed legislation and implemented regulations designed to control pharmaceutical and biological product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing. If healthcare policies or reforms intended to curb healthcare costs are adopted, or if we experience negative publicity with respect to the pricing of our products or the pricing of pharmaceutical drugs generally, the prices that we charge for any approved products may be limited, our commercial opportunity may be limited and/or our revenues from sales of our products may be negatively impacted.

We expect that other healthcare reform measures that may be adopted in the future, may result in more rigorous coverage criteria and in additional downward pressure on the price that we receive for any approved product. Any reduction in reimbursement from Medicare or other government programs may result in a similar reduction in payments from private payors. The implementation of cost containment measures or other healthcare reforms may prevent us from being able to generate revenue, attain profitability, or commercialize our drug candidates.

We are subject to anti-corruption laws, as well as export control laws, customs laws, sanctions laws and other laws governing our operations. If we fail to comply with these laws, we could be subject to civil or criminal penalties, other remedial measures and legal expenses, which could adversely affect our business, results of operations and financial condition.

We are subject to other laws and regulations governing our international operations, including regulations administered by the governments of the United States, and authorities in the European Union and in Japan, including applicable export control regulations, economic sanctions on countries and persons, customs requirements and currency exchange regulations, collectively referred to as the trade control laws.

We are also subject to anti-corruption laws, including the U.S. Foreign Corrupt Practices Act of 1977, as amended (“FCPA”), which prohibits any U.S. individual or business from paying, offering, or authorizing payment or offering of anything of value, directly or indirectly, to any foreign official, political party, or candidate for the purpose of influencing any act or decision of the foreign entity in order to assist the individual or business in obtaining or retaining business, and other state and national anti-bribery and anti-money laundering laws in the countries in which we conduct activities, including the French anti-corruption laws:

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The FCPA also obligates companies whose securities are listed in the United States to comply with accounting provisions requiring the company to maintain books and records that accurately and fairly reflect all transactions of the corporation, including international subsidiaries, and to devise and maintain an adequate system of internal accounting controls for international operations. Activities that violate the FCPA, even if they occur wholly outside the United States, can result in criminal and civil fines, imprisonment, disgorgement, oversight, and debarment from government contracts. The scope and enforcement of these laws is uncertain and subject to rapid change. Further, enforcement bodies have increased their scrutiny of interactions between healthcare companies and healthcare providers. This has resulted in an increase in the number of investigations, prosecutions, convictions and settlements in the healthcare industry. Responding to investigations can be both resource and time consuming and can divert management’s attention from the business. Any such investigation or settlement could increase our costs or otherwise have a material adverse effect on our business, outlook, financial position, income and growth.

The FCPA and other anti-corruption laws are interpreted broadly and prohibit companies and their employees, agents, contractors, and other collaborators from authorizing, promising, offering, or providing, directly or indirectly, improper payments or anything else of value to recipients in the public or private sector. We may engage third parties to sell our products outside the United States, to conduct clinical trials and/or to obtain necessary permits, licenses, patent registrations, and other regulatory approvals. We have direct or indirect interactions with officials and employees of government agencies or government-affiliated hospitals, universities, and other organizations. We can be held liable for the corrupt or other illegal activities of our employees, agents, contractors, and other collaborators, even if we do not explicitly authorize or have actual knowledge of such activities.

There is no complete assurance that we will be effective in ensuring our compliance with all applicable anti-corruption laws, including the FCPA, the French anti-corruption laws or other legal requirements, including trade control laws. If we are not in compliance with the FCPA, the French anti-corruption laws and other anti-corruption laws or trade control laws, we may be subject to criminal and civil penalties, disgorgement and other sanctions and

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remedial measures and legal expenses, which could have an adverse impact on our business, financial condition, results of operations and liquidity. Likewise, any investigation of any potential violations of the FCPA, the French anti-corruption laws, other anti-corruption laws or trade control laws by U.S. or other authorities could also have an adverse impact on our reputation, our business, results of operations and financial condition.

In addition, changes in our products and drug candidates or changes in applicable export or import laws and regulations may create delays in the introduction or provision of our products and drug candidates in other jurisdictions, prevent others from using our products and drug candidates or, in some cases, prevent the export or import of our products and drug candidates to certain countries, governments or persons altogether. Any limitation on our ability to export or provide our products and drug candidates could adversely affect our business, financial condition and results of operations.

Product liability and other lawsuits could divert our resources, result in substantial liabilities and reduce the commercial potential of our drug candidates.

The risk that we may be sued on product liability claims is inherent in the development and commercialization of our drug candidates. Side effects of, or manufacturing defects in, drugs that we develop could result in the deterioration of a patient’s condition, injury or even death. For example, our liability could be sought after by patients participating in the clinical trials in the context of the development of the therapeutic products tested and unexpected side effects resulting from the administration of these drugs. In addition, we could face liability due to undetected side-effects caused by the interaction of our drugs with other drugs following release of the drug candidate to the market. Once a product is approved for sale and commercialized, the likelihood of product liability lawsuits increases. Criminal or civil proceedings might be filed against us by patients, regulatory authorities, biopharmaceutical companies and any other third party using or marketing our drugs. These actions could include claims resulting from actions by our partners, licensees and subcontractors, over which we have little or no control. These lawsuits may divert our management from pursuing our business strategy and may be costly to defend. In addition, if we are held liable in any of these lawsuits, we may incur substantial liabilities, may be forced to limit or forgo further commercialization of the affected products and may suffer damage to our reputation.

We could be exposed to the risk of liability claims during the clinical development of our products, in particular product liability claims, related to the manufacture of therapeutic products and trials in humans and animals. We could be held liable by patients participating in clinical trials as part of the development of the therapeutic products tested for unexpected side effects resulting from the administration of these products.

We could also be held liable during the commercialization phase of our products. Criminal complaints or lawsuits could be filed or brought against us by patients, regulatory agencies, pharmaceutical companies and any other third parties using or marketing our products. These actions may include claims arising from acts of our partners, licensees or subcontractors, over which we have little or no control. Physicians and patients may not comply with any warnings that identify known potential adverse effects and patients who should not use our drug candidates.

We maintain product liability insurance coverage for our clinical trials at levels which we believe are appropriate for our clinical trials. Nevertheless, we cannot guarantee that the insurance policy taken out or the contractually limited indemnification, if applicable, granted by our subcontractors will be sufficient to cover the claims that could be brought against us or losses we may suffer.

If our liability, or that of our partners, licensees and subcontractors, was thereby activated, if we or our partners, licensees and subcontractors were unable to obtain and maintain appropriate insurance coverage at an acceptable cost or protect ourselves in any way against liability claims, this would seriously affect the commercialization of our products and, more generally, have a material adverse effect on our business, income, financial position and outlook for growth.

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We are subject to stringent and evolving U.S. and foreign laws, regulations, rules, contractual obligations, policies and other obligations related to data privacy and security. Our actual or perceived failure to comply with such obligations could lead to regulatory investigations or actions; litigation; fines and penalties; disruptions of our business operations; reputational harm; loss of revenue or profits; and other adverse business consequences.

In the ordinary course of business, we collect, receive, store, process, generate, use, transfer, disclose, make accessible, protect, secure, dispose of, transmit, and share (collectively, processing) personal data and other sensitive information, including proprietary and confidential business data, trade secrets, intellectual property, sensitive third-party data, business plans, transactions, and financial information (collectively, sensitive data).

Our data processing activities may subject us to numerous data privacy and security obligations, such as various laws, regulations, guidance, industry standards, external and internal privacy and security policies, contractual requirements, and other obligations relating to data privacy and security.

In the United States, federal, state, and local governments have enacted numerous data privacy and security laws, including data breach notification laws, personal data privacy laws, consumer protection laws (e.g., Section 5 of the Federal Trade Commission Act), and other similar laws (e.g., wiretapping laws). For example, the California Consumer Privacy Act of 2018 (“CCPA”) requires businesses to provide specific disclosures in privacy notices and honor requests of California residents to exercise certain privacy rights. The CCPA provides for civil penalties of up to $7,500 per violation and allows private litigants affected by certain data breaches to recover significant statutory damages. In addition, the California Privacy Rights Act of 2020 (“CPRA”), which becomes operative January 1, 2023, will expand the CCPA’s requirements, including applying to personal information of business representatives and employees and establishing a new regulatory agency to implement and enforce the law.

Other states, such as Virginia, Colorado, Utah and Connecticut have also passed comprehensive privacy laws, and similar laws are being considered in several other states, as well as at the federal and local levels. These developments may further complicate compliance efforts and may increase legal risk and compliance costs for us and the third parties upon whom we rely.

Outside the United States, an increasing number of laws, regulations, and industry standards may govern data privacy and security. For example, the European Union’s Regulation (EU) 2016/679 of 27 April 2016 on the protection of natural persons with regard to the processing of personal data and on the free movement of such data, as amended (“EU GDPR”), the United Kingdom’s GDPR (“UK GDPR”), Brazil’s General Data Protection Law (Lei Geral de Proteção de Dados Pessoais, or “LGPD”) (Law No. 13,709/2018), and China’s Personal Information Protection Law (“PIPL”) impose strict requirements for processing personal data.

Furthermore, we seek to obtain marketing authorization from the European Union for our drug candidates. Moreover, a significant portion of the personal data that we may use is managed by third parties (primarily clinical sites and CROs in clinical trials). The collection and use of personal health data in the European Union is governed by the provisions of the EU GDPR. Under the EU GDPR, companies may face temporary or definitive bans on data processing and other corrective actions; fines of up to €20 million or 4% of annual global revenue, whichever is greater; or private litigation related to processing of personal data brought by classes of data subjects or consumer protection organizations authorized at law to represent their interests.

In addition, we may be unable to transfer personal data from Europe and other jurisdictions to the United States or other countries due to data localization requirements or limitations on cross-border data flows. Europe and other jurisdictions have enacted laws requiring data to be localized or limiting the transfer of personal data to other countries. In particular, the EEA and the United Kingdom (“UK”) have significantly restricted the transfer of personal data to countries whose privacy laws it believes are inadequate. Other jurisdictions may adopt similarly stringent interpretations of their data localization and cross-border data transfer laws. Although there

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are currently various mechanisms that may be used to transfer personal data from the EEA and UK to the United States in compliance with law, such as the Trans-Atlantic Data Privacy Framework or the EEA and UK’s standard contractual clauses, being specified that these mechanisms of standard contractual clauses are subject to legal challenges, and there is no assurance that we can satisfy or rely on these measures to lawfully transfer personal data to the United States. If there is no lawful manner for us to transfer personal data from the EEA, the UK, or other jurisdictions to the United States, or if the requirements for a legally-compliant transfer are too onerous, we could face significant adverse consequences, including the interruption or degradation of our operations, the need to relocate part of or all of our business or data processing activities to other jurisdictions at significant expense, increased exposure to regulatory actions, substantial fines and penalties, the inability to transfer data and work with partners, vendors and other third parties, and injunctions against our processing or transferring of personal data necessary to operate our business. Some European regulators have prevented companies from transferring personal data out of Europe for allegedly violating the EU GDPR’s cross-border data transfer limitations.

In addition to data privacy and security laws, we may be contractually subject to industry standards adopted by industry groups and may become subject to such obligations in the future. We may also be bound by other contractual obligations related to data privacy and security, and our efforts to comply with such obligations may not be successful.

We may publish privacy policies, marketing materials, and other statements, such as compliance with certain certifications or self-regulatory principles, regarding data privacy and security. If these policies, materials or statements are found to be deficient, lacking in transparency, deceptive, unfair, or misrepresentative of our practices, we may be subject to investigation, enforcement actions by regulators, or other adverse consequences.

Obligations related to data privacy and security are quickly changing, becoming increasingly stringent, and creating regulatory uncertainty. Additionally, these obligations may be subject to differing applications and interpretations, which may be inconsistent or conflict among jurisdictions. Preparing for and complying with these obligations requires us to devote significant resources and may necessitate changes to our services, information technologies, systems, and practices and to those of any third parties that process personal data on our behalf.

We may at times fail (or be perceived to have failed) in our efforts to comply with our data privacy and security obligations. Moreover, despite our efforts, our personnel or third parties on whom we rely may fail to comply with such obligations, which could negatively impact our business operations. If we or the third parties on which we rely fail, or are perceived to have failed, to address or comply with applicable data privacy and security obligations, we could face significant consequences, including but not limited to: government enforcement actions (e.g., investigations, fines, penalties, audits, inspections, and similar); litigation (including class-action claims); additional reporting requirements and/or oversight; bans on processing personal data; and orders to destroy or not use personal data. Any of these events could have a material adverse effect on our reputation, business, or financial condition, including but not limited to: loss of customers; inability to process personal data or to operate in certain jurisdictions; limited ability to develop or commercialize our products; expenditure of time and resources to defend any claim or inquiry; adverse publicity; or substantial changes to our business model or operations.

If our information technology systems or data, or those of third parties upon which we rely, are or were compromised, we could experience adverse consequences resulting from such compromise, including but not limited to regulatory investigations or actions; litigation; fines and penalties; disruptions of our business operations; reputational harm; loss of revenue or profits; and other adverse consequences.

In the ordinary course of our business, we and the third parties upon which we rely may process sensitive data, and, as a result, we and the third parties upon which we rely face a variety of evolving threats, including but not limited to ransomware attacks, which could cause security incidents. Cyber-attacks, malicious internet-based

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activity, online and offline fraud and other similar activities threaten the confidentiality, integrity and availability of our sensitive data and information technology systems, and those of the third parties upon which we rely. Such threats are prevalent and continue to rise, are increasingly difficult to detect, and come from a variety of sources, including traditional computer “hackers,” threat actors, “hacktivists,” organized criminal threat actors, personnel (such as through theft or misuse), sophisticated nation states and nation-state-supported actors.

Some actors now engage and are expected to continue to engage in cyber-attacks, including without limitation nation-state actors for geopolitical reasons and in conjunction with military conflicts and defense activities. During times of war and other major conflicts, we and the third parties upon which we rely may be vulnerable to a heightened risk of these attacks, including retaliatory cyber-attacks, that could materially disrupt our systems and operations, supply chain and ability to produce, sell and distribute our services.

We and the third parties upon which we rely may be subject to a variety of evolving threats, including but not limited to social-engineering attacks (including through phishing attacks), malicious code (such as viruses and worms), malware (including as a result of advanced persistent threat intrusions), denial-of-service attacks (such as credential stuffing), credential harvesting, personnel misconduct or error, ransomware attacks, supply-chain attacks, software bugs, server malfunctions, software or hardware failures, loss of data or other information technology assets, adware, telecommunications failures, earthquakes, fires, floods and other similar threats.

In particular, severe ransomware attacks are becoming increasingly prevalent and can lead to significant interruptions in our operations, loss of sensitive data and income, reputational harm, and diversion of funds. Extortion payments may alleviate the negative impact of a ransomware attack, but we may be unwilling or unable to make such payments due to, for example, applicable laws or regulations prohibiting such payments.

Remote work has become more common and has increased risks to our information technology systems and data, as more of our employees utilize network connections, computers, and devices outside our premises or network, including working at home, while in transit and in public locations. Additionally, future or past business transactions (such as acquisitions or integrations) could expose us to additional cybersecurity risks and vulnerabilities, as our systems could be negatively affected by vulnerabilities present in acquired or integrated entities’ systems and technologies.

In addition, our reliance on third-party service providers could introduce new cybersecurity risks and vulnerabilities, including supply-chain attacks, and other threats to our business operations. We may rely on third-party service providers and technologies to operate critical business systems to process sensitive data in a variety of contexts, including, without limitation, cloud-based infrastructure, data center facilities, employee email, and other functions. We may also rely on third-party service providers to provide other products, services, parts, or otherwise to operate our business. Our ability to monitor these third parties’ information security practices is limited, and these third parties may not have adequate information security measures in place. If our third-party service providers experience a security incident or other interruption, we could experience adverse consequences. While we may be entitled to damages if our third-party service providers fail to satisfy their privacy or security-related obligations to us, any award may be insufficient to cover our damages, or we may be unable to recover such award. In addition, supply-chain attacks have increased in frequency and severity, and we cannot guarantee that third parties’ infrastructure in our supply chain or our third-party partners’ supply chains have not been compromised. One of our CROs has experienced a data breach that involved personal data being compromised, affecting all the CRO’s customers, including fully pseudonymized and encoded electronic case report forms relating to 14 of our trials. While our Data Protection Committee concluded in October 2021 that there is no critical risk to the privacy of data subjects, we have conducted additional corrective and preventive measures to ensure any such data breach incident can be prevented in the future (including root cause analysis audits and risk analysis).

Any of the previously identified or similar threats could cause a security incident or other interruption that could result in unauthorized, unlawful, or accidental acquisition, modification, destruction, loss, alteration, encryption, disclosure of, or access to our sensitive data or our information technology systems, or those of the

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third parties upon whom we rely. A security incident or other interruption could disrupt our ability (and that of third parties upon whom we rely) to provide our services.

We may expend significant resources or modify our business activities to try to protect against security incidents. Additionally, certain data privacy and security obligations may require us to implement and maintain specific security measures or industry-standard or reasonable security measures to protect our information technology systems and sensitive data.

While we have implemented security measures designed to protect against security incidents, there can be no assurance that these measures will be effective. We may be unable in the future to detect vulnerabilities in our information technology systems because such threats and techniques change frequently, are often sophisticated in nature, and may not be detected until after a security incident has occurred. Further, we may experience delays in developing and deploying remedial measures designed to address any such identified vulnerabilities.

Applicable data privacy and security obligations may require us to notify relevant stakeholders of security incidents. Such disclosures are costly, and the disclosure or the failure to comply with such requirements could lead to adverse consequences.

If we (or a third party upon whom we rely) experience a security incident or are perceived to have experienced a security incident, we may experience adverse consequences. These consequences may include: government enforcement actions (for example, investigations, fines, penalties, audits, and inspections); additional reporting requirements and/or oversight; restrictions on processing sensitive data (including personal data); litigation (including class claims); indemnification obligations; negative publicity; reputational harm; monetary fund diversions; interruptions in our operations (including availability of data); financial loss; and other similar harms. Security incidents and attendant consequences may cause customers to stop using our services, deter new customers from using our services, and negatively impact our ability to grow and operate our business.

Our contracts may not contain limitations of liability, and even where they do, there can be no assurance that limitations of liability in our contracts are sufficient to protect us from liabilities, damages, or claims related to our data privacy and security obligations. We cannot be sure that our insurance coverage will be adequate or sufficient to protect us from or to mitigate liabilities arising out of our privacy and security practices, that such coverage will continue to be available on commercially reasonable terms or at all, or that such coverage will pay future claims.

Risks Related to the Offering, Ownership of Our ADSs and Our Status as a Non-U.S. Company with Foreign Private Issuer Status

There has been no market for our ADSs prior to the U.S. offering and an active and liquid market for our securities may fail to develop, which could harm the market price of our ADSs.

Although our ordinary shares have been traded on Euronext Paris since mid-2015, there has been no public market on a U.S. national securities exchange for our ADSs in the United States. Although we anticipate that our ADSs will be approved for listing on the Nasdaq Global Market, an active trading market for our ADSs may never develop or be sustained following the offering. The offering price of our ADSs was determined through negotiations between us and the underwriters based on a number of factors. This offering price may not be indicative of the market price of our ADSs after the offering. In the absence of an active trading market for our ADSs, investors may not be able to sell their ADSs at or above the offering price or at the time that they would like to sell.

If we do not achieve our projected development and commercialization goals in the timeframes we announce and expect, our business will be harmed, and the price of our securities could decline as a result.

We sometimes estimate for planning purposes the timing of the accomplishment of various scientific, clinical, regulatory and other product development objectives. These milestones may include our expectations

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regarding the commencement or completion of scientific studies, clinical trials, the submission of regulatory filings, or commercialization objectives. From time to time, we may publicly announce the expected timing of some of these milestones, such as the completion of an ongoing clinical trial, the initiation of other clinical programs, receipt of marketing approval, or a commercial launch of a product. The achievement of many of these milestones may be outside of our control. All of these milestones are based on a variety of assumptions which may cause the timing of achievement of the milestones to vary considerably from our estimates, including:

If we fail to achieve announced milestones in the timeframes we expect, the commercialization of our drug candidates may be delayed, our business and results of operations may be harmed, and the trading price of the ADSs may decline as a result.

We may be a “passive foreign investment company” for U.S. federal income tax purposes, which could result in adverse U.S. federal income tax consequences to U.S. investors.

Generally, if, for any taxable year, at least 75% of our gross income is passive income (“income test”), or at least 50% of the value of our assets (based on an average of the quarterly values of the assets during a taxable year) is attributable to assets that produce passive income or are held for the production of passive income, including cash, we would be characterized as a passive foreign investment company (“PFIC”) for U.S. federal income tax purposes. For purposes of these tests, passive income includes, among other things, dividends, interest, and gains from the sale or exchange of investment property and rents or royalties other than rents or royalties which are received from unrelated parties in connection with the active conduct of a trade or business. Cash and cash equivalents are generally treated as passive assets. Goodwill is treated as an active asset to the extent associated with business activities that produce active income. For purposes of the PFIC rules, a non-U.S. corporation that owns, directly or indirectly, at least 25% by value of the equity interests of another corporation or partnership is treated as if it held its proportionate share of the assets of the other corporation or partnership, and received directly its proportionate share of the income of the other corporation or partnership. Equity interests of less than 25% by value in any other corporation or partnership are treated as passive assets, regardless of the nature of the other corporation or partnership’s business. If we are a PFIC for any taxable year in which a U.S. Holder (as defined in “Material United States Federal Income and French Tax Considerations—Material U.S. Federal Income Tax Considerations for U.S. Holders”) holds an ADS, certain adverse U.S. federal income tax consequences could apply to such U.S. Holder including increased tax liability on disposition gains and certain “excess distributions” and additional reporting requirements. See “Material United States Federal Income and French Tax Considerations—Material U.S. Federal Income Tax Considerations for U.S. Holders—Passive Foreign Investment Company Rules.”

Based on our analysis of our financial statements, activities and relevant market and shareholder data, we do not believe that we were a PFIC for the taxable year ended December 31, 2022. Whether we are a PFIC for any

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taxable year will depend on the composition of our income and the composition, nature and value of our assets from time to time (including the value of our goodwill, which may be determined by reference to the value of our ADSs, which could fluctuate considerably). We currently do not generate product revenues and therefore we may be a PFIC for any taxable year in which we do not generate sufficient amounts of non-passive income to offset our passive financing income. As a result, there can be no assurance that we will not be treated as a PFIC for the current or any future taxable year and our U.S. counsel expresses no opinion with respect to our PFIC status for any prior, current or future taxable year. Even if we determine that we are not a PFIC for a taxable year, there can be no assurance that the Internal Revenue Service, or the IRS, will agree with our conclusion and that the IRS would not successfully challenge our position. Each U.S. holder is strongly urged to consult its tax advisor regarding these issues and any available elections to mitigate such tax consequences.

If a United States person is treated as owning at least 10% of the value or voting power of our ADSs, such holder may be subject to adverse U.S. federal income tax consequences.

If a United States person is treated as owning (directly, indirectly, or constructively) at least 10% of the aggregate value or voting power of our ADSs, such person may be treated as a “United States shareholder” with respect to each “controlled foreign corporation” in our group (if any), which may subject such person to adverse U.S. federal income tax consequences. Our group currently includes one U.S. subsidiary corporation and, therefore, under current law our current non-U.S. subsidiary and any future newly formed or acquired non-U.S. subsidiaries that are treated as corporations for U.S. federal income tax purposes will be treated as controlled foreign corporations, regardless of whether we are treated as a controlled foreign corporation. A United States shareholder of a controlled foreign corporation generally is required to report annually and include in its U.S. taxable income its pro rata share of “Subpart F income,” “global intangible low-taxed income,” and investments in U.S. property by controlled foreign corporations, regardless of whether we make any distributions. An individual that is a United States shareholder with respect to a controlled foreign corporation generally would not be allowed certain tax deductions or foreign tax credits that would be available to a United States shareholder that is a U.S. corporation. Failure to comply with these reporting obligations may subject a United States shareholder to significant monetary penalties and may prevent the statute of limitations with respect to such shareholder’s U.S. federal income tax return for the year for which reporting was due from starting. We cannot provide any assurances that we will assist investors in determining whether we are treated as a controlled foreign corporation or whether any holder of our ADSs is treated as a United States shareholder with respect to any such controlled foreign corporation or furnish to any United States shareholders information that may be necessary to comply with the aforementioned reporting and tax paying obligations. The United States Internal Revenue Service provided limited guidance on situations in which investors may rely on publicly available information to comply with their reporting and tax paying obligations with respect to foreign-controlled CFCs. Each U.S. holder of our ADSs should consult its advisors regarding the potential application of these rules to an investment in our ADSs.

We have broad discretion in the use of the net proceeds from the global offering and may use them in ways with which you do not agree and in ways that may not increase the value of your investment.

Our management will have broad discretion in the application of the net proceeds that we receive from the global offering. We may spend or invest these proceeds in a way with which our shareholders and ADS holders disagree. The failure by our management to apply these funds effectively could harm our business and financial condition. Pending their use, we may invest the net proceeds from the global offering in a manner that does not produce income or that loses value. These investments may not yield a favorable return to our investors.

If you purchase ADSs in the offering, you will experience substantial and immediate dilution.

If you purchase ADSs in the offering, you will experience substantial and immediate dilution of $7.21 per ADS in pro forma net tangible book value as of June 30, 2023, after giving effect to the global offering of approximately €201.1 million ($212.2 million) at the initial offering price of €10.9864 per ordinary share ($11.60 per ADS), after deducting the underwriting commissions and estimated offering expenses payable by us. This dilution is due in large part to the fact that our earlier investors paid substantially less than the offering price

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when they purchased their ordinary shares. You will experience additional dilution upon exercise of any outstanding warrants to purchase ordinary shares or if we otherwise issue additional ordinary shares or ADSs below the offering price. For a further description of the dilution that you will experience immediately after the offering, see the section of this prospectus titled “Dilution.”

Future, or the possibility of future sales, of a substantial number sales of our ordinary shares or ADSs by existing shareholders could depress the market price of the ordinary shares.

Future sales of a substantial number of our ADSs, or the perception that such sales will occur, could cause a decline in the market price of our ADSs. Based upon the number of shares outstanding as of June 30, 2023, after giving effect to the closing of the offering, we will have 62,873,068 ordinary shares outstanding (including ordinary shares in the form of ADSs), assuming the underwriters do not exercise their option to purchase 3,048,825 additional ADSs. ADSs issued and sold in the U.S. offering may be resold in the public market immediately without restriction, unless purchased by our affiliates. A significant portion of these ADSs will be subject to the lock-up agreements described in “Ordinary Shares and ADSs Eligible for Future Sale” and “Underwriters.” If, after the end of such lock-up agreements, these shareholders or ADS holders sell substantial amounts of ADSs in the public market, or the market perceives that such sales may occur, the market price of our ADSs and our ability to raise capital through an issuance of equity securities in the future could be adversely affected.

The rights of shareholders in companies subject to French corporate law differ in material respects from the rights of shareholders of corporations incorporated in the United States.

We are a French company with limited liability. Our corporate affairs are governed by our by-laws and by the laws governing companies incorporated in France. The rights of shareholders and the responsibilities of members of our Board are in many ways different from the rights and obligations of shareholders in companies governed by the laws of U.S. jurisdictions. For example, in the performance of its duties, our Board is required by French law to consider the interests of our company, its shareholders, its employees and other stakeholders, rather than solely our shareholders and/or creditors. It is possible that some of these parties will have interests that are different from, or in addition to, your interests as a shareholder or holder of ADSs. See the sections of this prospectus titled “Management—Board Practices—Corporate Governance Practices” and “Description of Share Capital.”

U.S. investors may have difficulty enforcing civil liabilities against our company and directors and senior management and the experts named in this prospectus.

Certain members of our Board and senior management and certain experts named in this prospectus are non-residents of the United States, and all or a substantial portion of our assets and the assets of such persons are located outside the United States. As a result, it may not be possible to serve process on such persons or us in the United States or to enforce judgments obtained in U.S. courts against them or us based on civil liability provisions of the securities laws of the United States. Additionally, it may be difficult to assert U.S. securities law claims in actions originally instituted outside of the United States. Courts outside the United States may refuse to hear a U.S. securities law claim because non-U.S. courts may not be the most appropriate forums in which to bring such a claim. Even if a court outside the United States agrees to hear a claim, it may determine that the law of the jurisdiction in which the non-U.S. court resides, and not U.S. law, is applicable to the claim. Further, if U.S. law is found to be applicable, the content of applicable U.S. law must be proved as a fact, which can be a time-consuming and costly process, and certain matters of procedure would still be governed by the law of the jurisdiction in which the non-U.S. court resides. In particular, there is some doubt as to whether French courts would recognize and enforce certain civil liabilities under U.S. securities laws in original actions or judgments of U.S. courts based upon these civil liability provisions. In addition, awards of punitive damages in actions brought in the United States or elsewhere may be unenforceable in France. An award for monetary damages under the U.S. securities laws would be considered punitive if it does not seek to compensate the

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claimant for loss or damage suffered but is intended to punish the defendant. French law provides that a shareholder, or a group of shareholders, may initiate a legal action to seek indemnification from the directors of a corporation in the corporation’s interest if it fails to bring such legal action itself. If so, any damages awarded by the court are paid to the corporation and any legal fees relating to such action may be borne by the relevant shareholder or the group of shareholders.

The enforceability of any judgment in France will depend on the particular facts of the case as well as the laws and treaties in effect at the time. The United States and France do not currently have a treaty providing for recognition and enforcement of judgments, other than arbitration awards, in civil and commercial matters. See “Enforcement of Civil Liabilities.”

You may face difficulties protecting your interests, and your ability to protect your rights through the U.S. federal courts may be limited because we are incorporated under the laws of France, all of our assets are in the European Union and a majority of our directors and executive officers reside outside the United States.

We are constituted under the laws of France. A majority of our officers and directors reside outside the United States. In addition, a substantial portion of their assets and our assets are located outside of the United States. As a result, you may have difficulty serving legal process within the United States upon us or any of these persons. You may also have difficulty enforcing, both in and outside of the United States, judgments you may obtain in U.S. courts against us or these persons in any action, including actions based upon the civil liability provisions of U.S. Federal or state securities laws. Furthermore, there is substantial doubt as to the enforceability in France against us or against any of our directors, officers and the expert named in this prospectus who are not residents of the United States, in original actions or in actions for enforcement of judgments of U.S. courts, of liabilities based solely upon the civil liability provisions of the U.S. federal securities laws. In addition, shareholders in French corporations may not have standing to initiate a shareholder derivative action in U.S. federal courts.

As a result, our public shareholders may have more difficulty in protecting their interests through actions against us, our management, our directors or our major shareholders than would shareholders of a corporation incorporated in a jurisdiction in the United States.

The dual listing of our ordinary shares and the ADSs may adversely affect the liquidity and value of the ADSs.

Following this global offering and after the ADSs begin trading on the Nasdaq Global Market, our ordinary shares will continue to be listed on Euronext Paris. Trading of the ADSs or ordinary shares in these markets will take place in different currencies (U.S. dollars on Nasdaq and euros on Euronext Paris), and at different times (resulting from different time zones, different trading days and different public holidays in the United States and France). The trading prices of our ordinary shares on these two markets may differ due to these and other factors. Any decrease in the price of our ordinary shares on Euronext Paris could cause a decrease in the trading price of the ADSs on Nasdaq. Investors could seek to sell or buy our ordinary shares to take advantage of any price differences between the markets through a practice referred to as arbitrage. Any arbitrage activity could create unexpected volatility in both our share prices on one exchange, and the ordinary shares available for trading on the other exchange. In addition, holders of ADSs will not be immediately able to surrender their ADSs and withdraw the underlying ordinary shares for trading on the other market without effecting necessary procedures with the depositary. This could result in time delays and additional cost for holders of ADSs. We cannot predict the effect of this dual listing on the value of our ordinary shares and the ADSs. However, the dual listing of our ordinary shares and the ADSs may reduce the liquidity of these securities in one or both markets and may adversely affect the development of an active trading market for the ADSs in the United States.

Our by-laws and French corporate law contain provisions that may delay or discourage a takeover attempt.

Provisions contained in our by-laws and French corporate law could make it more difficult for a third party to acquire us, even if doing so might be beneficial to our shareholders. In addition, provisions of our by-laws

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impose various procedural and other requirements, which could make it more difficult for shareholders to effect certain corporate actions. These provisions include the following:

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Existing and potential investors in our ordinary shares or ADSs may have to request the prior authorization from the French Ministry of Economy prior to acquiring a significant ownership position in our ordinary shares or ADSs.

Under French law, direct and indirect acquisition of control of all or part of a branch of activity, and investments of more than 25% by foreign individuals or entities (except, in the last case, EU/EEA investors) in a French company deemed to be a strategic industry is subject to prior authorization of the French Ministry of Economy pursuant to Articles L. 151-1 et seq. and R. 151-1 et seq. of the French Monetary and Financial Code.

If an investment requiring the prior authorization of the French Minister of Economy is completed without such authorization having been granted, the French Minister of Economy might direct the relevant investor to (i) submit a request for authorization, (ii) have the previous situation restored at its own expense or (iii) amend the investment. The relevant investor might also be found criminally liable and might be sanctioned with a fine which cannot exceed the greater of: (i) twice the amount of the relevant investment, (ii) 10% of the annual turnover before tax of the target company and (iii) €5 million (for an entity) or €1 million (for an individual). The French Minister of Economy may also adopt precautionary measures it deems necessary to protect strategic sovereign assets , including the suspension of voting rights or the prohibition or limitation of the distribution of dividends and remuneration attached to shares whose ownership by the investor should have been subject to prior authorization.

In the context of the COVID-19 pandemic, the Decree (décret) No. 2020-892 dated July 22, 2020, as amended by the Decree (décret) No. 2020-1729 dated December 28, 2020, on December 22, 2021 by the Decree (décret) n° 2021-1758 and lastly on December 23, 2022 by the Decree (décret) n° 2022-1622, has implemented a 10% threshold of the voting rights for the non-EU/EEA investments made (i) in an entity incorporated under the laws of France and (ii) whose shares are admitted to trading on a regulated market, in addition to the 25% above-mentioned threshold. Set to expire on December 31, 2023, this 10% threshold could become permanent. The transactions falling within the scope of the Decree (décret) No. 2020-892, as amended, benefit from a “fast-track procedure” pursuant to which the investor is exempt from the authorization request provided for in Article R. 151-5 of the Monetary and Financial Code, provided that the investment project has been the subject of prior notification to the French Minister of Economy and that the transaction is carried out within six months following the notification. Unless the French Minister of Economy objects, the authorization is granted at the end of a period of ten working days following notification.

Failure to comply with such measures could result in significant consequences in the concerned investment. Such measures could also delay or discourage a takeover or more broadly a foreign investment attempt, and we cannot predict whether these measures will result in a lower or more volatile market price of our ADSs.

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For more details on the French foreign investment control regime see “Limitations Affecting Shareholders of a French Company.”

You may not be able to exercise your right to vote the ordinary shares underlying your ADSs.

Holders of ADSs may exercise voting rights with respect to the ordinary shares represented by the ADSs only in accordance with the provisions of the deposit agreement. The deposit agreement provides that, upon receipt of notice of any meeting of holders of our ordinary shares, the depositary will fix a record date for the determination of ADS holders who shall be entitled to give instructions for the exercise of voting rights. Upon timely receipt of notice from us, if we so request, the depositary shall distribute to the holders as of the record date (i) the notice of the meeting or solicitation of consent or proxy sent by us and (ii) a statement as to the manner in which instructions may be given by the holders.

Purchasers of ADSs may instruct the depositary of their ADSs to vote the ordinary shares underlying their ADSs. Otherwise, purchasers of ADSs will not be able to exercise voting rights unless they withdraw the ordinary shares underlying the ADSs they hold. However, a holder of ADSs may not know about the meeting far enough in advance to withdraw those ordinary shares. If we ask for a holder of ADSs’ instructions, the depositary, upon timely notice from us, will notify him or her of the upcoming vote and arrange to deliver our voting materials to him or her. We cannot guarantee to any holder of ADSs that he or she will receive the voting materials in time to ensure that he or she can instruct the depositary to vote his or her ordinary shares or to withdraw his or her ordinary shares so that he or she can vote them. If the depositary does not receive timely voting instructions from a holder of ADSs, it may give a proxy to a person designated by us to vote the ordinary shares underlying his or her ADSs. In addition, the depositary and its agents are not responsible for failing to carry out voting instructions or for the manner of carrying out voting instructions. This means that a holder of ADSs may not be able to exercise his or her right to vote, and there may be nothing he or she can do if the ordinary shares underlying his or her ADSs are not voted as he or she requested.

Purchasers of ADSs are not holders of our ordinary shares.

A holder of ADSs will not be treated as one of our shareholders and will not have direct shareholder rights. French law governs our shareholder rights. The depositary will be the holder of the ordinary shares underlying ADSs held by purchasers of ADSs. Purchasers of ADSs will have ADS holder rights. The deposit agreement among us, the depositary and purchasers of ADSs, as ADS holders, and all other persons directly and indirectly holding ADSs, sets out ADS holder rights, as well as the rights and obligations of the depositary.

A double voting right is attached to each registered ordinary share (except treasury shares) that is held in the name of the same shareholder for at least two years. However, the ordinary shares underlying our ADSs will not be entitled to double voting rights as the depositary will hold the ordinary shares underlying our ADSs in bearer form.

The right as a holder of ADSs to participate in any future preferential subscription rights or to elect to receive dividends in shares may be limited, which may cause dilution to the holdings of purchasers of ADSs in the ADS offering.

According to French law, if we issue additional securities for cash, current shareholders will have preferential subscription rights for these securities on a pro rata basis unless they waive those rights at an extraordinary meeting of our shareholders by a two-thirds majority vote or individually by each shareholder. However, ADS holders will not be entitled to exercise or sell such rights unless we register the rights and the securities to which the rights relate under the Securities Act or an exemption from the registration requirements is available. In addition, the deposit agreement provides that the depositary will not make rights available to purchasers of ADSs unless the distribution to ADS holders of both the rights and any related securities are either registered under the Securities Act or exempted from registration under the Securities Act. Further, if we offer

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holders of our ordinary shares the option to receive dividends in either cash or shares, under the deposit agreement the depositary may require satisfactory assurances from us that extending the offer to holders of ADSs does not require registration of any securities under the Securities Act before making the option available to holders of ADSs. We are under no obligation to file a registration statement with respect to any such rights or securities or to endeavor to cause such a registration statement to be declared effective. Moreover, we may not be able to establish an exemption from registration under the Securities Act. Accordingly, ADS holders may be unable to participate in our rights offerings or to elect to receive dividends in shares and may experience dilution in their holdings. In addition, if the depositary is unable to sell rights that are not exercised or not distributed or if the sale is not lawful or reasonably practicable, it will allow the rights to lapse, in which case you will receive no value for these rights.

Purchasers of ADSs may be subject to limitations on the withdrawal of the underlying ordinary shares.

Temporary delays in the cancellation of ADSs and withdrawal of the underlying ordinary shares may arise because the depositary has closed its transfer books or we have closed our transfer books, the transfer of ordinary shares is blocked to permit voting at a shareholders’ meeting or we are paying a dividend on our ordinary shares. In addition, a holder of ADSs may not be able to cancel his or her ADSs and withdraw the underlying ordinary shares when he or she owes money for fees, taxes and similar charges and when it is necessary to prohibit withdrawals in order to comply with any laws or governmental regulations that apply to ADSs or to the withdrawal of ordinary shares or other deposited securities. See the section of this prospectus titled “Description of American Depositary Shares.”

ADSs holders may not be entitled to a jury trial with respect to claims arising under the deposit agreement, which could result in less favorable outcomes to the plaintiffs in any such action.

The deposit agreement governing the ADSs representing our ordinary shares provides that, to the fullest extent permitted by law, ADS holders waive the right to a jury trial of any claim they may have against us or the depositary arising out of or relating to our shares, the ADSs or the deposit agreement, including any claim under the U.S. federal securities laws.

If we or the depositary opposed a jury trial demand based on the waiver, the court would determine whether the waiver was enforceable based on the facts and circumstances of that case in accordance with the applicable state and federal law. To our knowledge, the enforceability of a contractual pre-dispute jury trial waiver in connection with claims arising under the federal securities laws has not been finally adjudicated by the United States Supreme Court. However, we believe that a contractual pre-dispute jury trial waiver provision is generally enforceable, including under the laws of the State of New York, which govern the deposit agreement, by a federal or state court in the City of New York, which has non-exclusive jurisdiction over matters arising under the deposit agreement. In determining whether to enforce a contractual pre-dispute jury trial waiver provision, courts will generally consider whether a party knowingly, intelligently and voluntarily waived the right to a jury trial. We believe that this is the case with respect to the deposit agreement and the ADSs. It is advisable that you consult legal counsel regarding the jury waiver provision before entering into the deposit agreement.

If you or any other holders or beneficial owners of ADSs bring a claim against us or the depositary in connection with matters arising under the deposit agreement or the ADSs, including claims under federal securities laws, you or such other holder or beneficial owner may not be entitled to a jury trial with respect to such claims, which may have the effect of limiting and discouraging lawsuits against us and the depositary. If a lawsuit is brought against either or both of us and the depositary under the deposit agreement, it may be heard only by a judge or justice of the applicable trial court, which would be conducted according to different civil procedures and may result in different outcomes than a trial by jury would have, including results that could be less favorable to the plaintiffs in any such action.

Nevertheless, if this jury trial waiver provision is not permitted by applicable law, an action could proceed under the terms of the deposit agreement with a jury trial. No condition, stipulation or provision of the deposit

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agreement or ADSs serves as a waiver by any holder or beneficial owner of ADSs or by us or the depositary of compliance with U.S. federal securities laws and the rules and regulations promulgated thereunder.

As a foreign private issuer, we are exempt from a number of rules under the U.S. securities laws and are permitted to file less information with the SEC than a U.S. company. This may limit the information available to holders of ADSs.

We are a foreign private issuer, as defined in the SEC’s rules and regulations and, consequently, we are not subject to all of the disclosure requirements applicable to public companies organized within the United States. For example, we are exempt from certain rules under the Exchange Act that regulate disclosure obligations and procedural requirements related to the solicitation of proxies, consents or authorizations applicable to a security registered under the Exchange Act, including the U.S. proxy rules under Section 14 of the Exchange Act. In addition, our officers and directors are exempt from the reporting and “short-swing” profit recovery provisions of Section 16 of the Exchange Act and related rules with respect to their purchases and sales of our securities. Moreover, while we currently make annual and semi-annual filings with respect to our listing on Euronext Paris and expect to file financial reports on an annual and semi-annual basis, we will not be required to file periodic reports and financial statements with the SEC as frequently or as promptly as U.S. public companies and will not be required to file quarterly reports on Form 10-Q or current reports on Form 8-K under the Exchange Act. Accordingly, there will be less publicly available information concerning our company than there would be if we were not a foreign private issuer.

As a foreign private issuer, we are permitted, and we expect, to follow certain home country practices in relation to corporate governance matters that differ significantly from Nasdaq’s corporate governance standards. These practices may afford less protection to shareholders than they would enjoy if we complied fully with the corporate governance standards of the Nasdaq Global Market.

As a foreign private issuer listed on the Nasdaq Global Market, we will be subject to Nasdaq’s corporate governance standards. However, Nasdaq rules provide that foreign private issuers are permitted to follow home country corporate governance practices in lieu of Nasdaq’s corporate governance standards as long as notification is provided to Nasdaq of the intention to take advantage of such exemptions. We intend to rely on exemptions for foreign private issuers and follow French corporate governance practices in lieu of Nasdaq’s corporate governance standards, to the extent possible. Certain corporate governance practices in France, which is our home country, may differ significantly from Nasdaq corporate governance standards. For example, as a French company, neither the corporate laws of France nor our by-laws require a majority of our directors to be independent and we can include non-independent directors as members of our remuneration committee, and our independent directors are not required to hold regularly scheduled meetings at which only independent directors are present.

We are also exempt from provisions set forth in Nasdaq rules which require an issuer to provide in its by-laws for a generally applicable quorum, and that such quorum may not be less than one-third of the outstanding voting stock. Consistent with French law, our by-laws provide that a quorum requires the presence of shareholders having at least (i) 20% of the shares entitled to vote in the case of an ordinary shareholders’ general meeting or at an extraordinary shareholders’ general meeting where shareholders are voting on a capital increase by capitalization of reserves, profits or share premium, or (ii) 25% of the shares entitled to vote in the case of any other extraordinary shareholders’ general meeting. If a quorum is not present, the meeting is adjourned. There is no quorum requirement when an ordinary general meeting is reconvened, but the reconvened meeting may consider only questions which were on the agenda of the adjourned meeting. When an extraordinary general meeting is reconvened, the quorum required is 20% of the shares entitled to vote, except where the reconvened meeting is considering capital increases through capitalization of reserves, profits or share premium. For these matters, no quorum is required at the reconvened meeting. If a quorum is not present at a reconvened meeting requiring a quorum, then the meeting may be adjourned for a maximum of two months.

As a foreign private issuer, we are required to comply with Rule 10A-3 of the Exchange Act, relating to audit committee composition and responsibilities. Under French law, the audit committee may only have an

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advisory role and appointment of our statutory auditors, in particular, must be decided by the shareholders at our annual meeting. Therefore, our shareholders may be afforded less protection than they otherwise would have under Nasdaq’s corporate governance standards applicable to U.S. domestic issuers. For an overview of our corporate governance practices, see “Management—Board Practices—Corporate Governance Practices.”

We are an “emerging growth company” under the JOBS Act and will be able to avail ourselves of reduced disclosure requirements applicable to emerging growth companies, which could make our ADSs less attractive to investors.

We are an “emerging growth company,” as defined in the JOBS Act, and we intend to take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not “emerging growth companies”, including not being required to comply with the auditor attestation requirements of Section 404(b) of the Sarbanes-Oxley Act of 2002 (“Sarbanes-Oxley Act”), and exemptions from the requirements of holding a nonbinding advisory vote on executive compensation and shareholder approval of any golden parachute payments not previously approved. In addition, Section 107 of the JOBS Act also provides that an emerging growth company can take advantage of the extended transition period provided in Section 7(a)(2)(B) of the Securities Act, for complying with new or revised accounting standards. We will not take advantage of the extended transition period provided under Section 7(a)(2)(B) of the Securities Act for complying with new or revised accounting standards. Since IFRS makes no distinction between public and private companies for purposes of compliance with new or revised accounting standards, the requirements for our compliance as a private company and as a public company are the same.

We cannot predict if investors will find our ADSs less attractive because we may rely on these exemptions. If some investors find our ADSs less attractive as a result, there may be a less active trading market for our ADSs and the price of our ADSs may be more volatile. We may take advantage of these reporting exemptions until we are no longer an emerging growth company. We will remain an emerging growth company until the earliest of (1) the last day of the fiscal year in which we have total annual gross revenue of $1.235 billion or more; (2) the last day of our fiscal year following the fifth anniversary of the date of the completion of the offering; (3) the date on which we have issued more than $1.0 billion in nonconvertible debt during the previous three years; and (4) the date on which we are deemed to be a large accelerated filer under the rules of the SEC.

We may lose our foreign private issuer status in the future, which could result in significant additional cost and expense.

While we currently qualify as a foreign private issuer, the determination of foreign private issuer status is made annually on the last business day of an issuer’s most recently completed second fiscal quarter and, accordingly, the next determination will be made with respect to us on June 30, 2024. In the future, we could lose our foreign private issuer status if we fail to meet the requirements necessary to maintain our foreign private issuer status as of the relevant determination date. We will remain a foreign private issuer until such time that more than 50% of our outstanding voting securities are held by U.S. residents and any of the following three circumstances applies: (i) the majority of our executive officers or directors are U.S. citizens or residents; (ii) more than 50% of our assets are located in the United States; or (iii) our business is administered principally in the United States. For additional information relating to our principal shareholders, see “Principal Shareholders.”

The regulatory and compliance costs to us under U.S. securities laws as a U.S. domestic issuer may be significantly more than costs we incur as a foreign private issuer. If we are not a foreign private issuer, we will be required to file periodic reports and registration statements on U.S. domestic issuer forms with the SEC, which are more detailed and extensive in certain respects than the forms available to a foreign private issuer. We would be required under current SEC rules to prepare our financial statements in accordance with U.S. GAAP, rather than IFRS, and modify certain of our policies to comply with corporate governance practices associated with U.S. domestic issuers. Such conversion of our financial statements to U.S. GAAP would involve significant time

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and cost. In addition, we may lose our ability to rely upon exemptions from certain corporate governance requirements on U.S. stock exchanges that are available to foreign private issuers such as the ones described herein and exemptions from procedural requirements related to the solicitation of proxies.

General Risk Factors

We may not be successful in obtaining or maintaining necessary rights to product components and processes for our development pipeline through acquisitions and in-licenses.

The growth of our business may depend in part on our ability to acquire, in-license or use third-party proprietary rights. For example, our drug candidates may require specific formulations to work effectively and efficiently, we may develop drug candidates containing our compounds and pre-existing pharmaceutical compounds, or we may be required by the FDA or comparable foreign regulatory authorities to provide a companion diagnostic test or tests with our drug candidates, any of which could require us to obtain rights to use intellectual property held by third parties. In addition, with respect to any patents we may co-own with third parties, we may require licenses to such co-owner’s interest to such patents. We may be unable to acquire or in-license any compositions, methods of use, processes or other third-party intellectual property rights from third parties that we identify as necessary or important to our business operations. In addition, we may fail to obtain any of these licenses at a reasonable cost or on reasonable terms, if at all. Were that to happen, we may need to cease use of the compositions or methods covered by those third-party intellectual property rights, and may need to seek to develop alternative approaches that do not infringe on those intellectual property rights, which may entail additional costs and development delays, even if we were able to develop such alternatives, which may not be feasible. Even if we are able to obtain a license, it may be non-exclusive, which means that our competitors may also receive access to the same technologies licensed to us. In that event, we may be required to expend significant time and resources to develop or license replacement technology.

Additionally, we sometimes collaborate with academic institutions to accelerate our preclinical research or development under written agreements with these institutions. In certain cases, these institutions provide us with an option to negotiate a license to any of the institution’s rights in technology resulting from the collaboration. Even if we hold such an option, we may be unable to negotiate a license from the institution within the specified timeframe or under terms that are acceptable to us. If we are unable to do so, the institution may offer the intellectual property rights to others, potentially blocking our ability to pursue our program.

The licensing and acquisition of third-party intellectual property rights is a competitive area, and companies that may be more established or have greater resources than we do may also be pursuing strategies to license or acquire third-party intellectual property rights that we may consider necessary or attractive in order to commercialize our drug candidates. More established companies may have a competitive advantage over us due to their size, cash resources and greater clinical development and commercialization capabilities. In addition, companies that perceive us to be a competitor may be unwilling to assign or license rights to us. There can be no assurance that we will be able to successfully complete these types of negotiations and ultimately acquire the rights to the intellectual property surrounding the additional drug candidates that we may seek to develop or market. If we are unable to successfully obtain rights to required third-party intellectual property or to maintain the existing intellectual property rights we have, we may have to abandon development of certain programs and our business financial condition, results of operations and prospects could suffer.

The market price of our equity securities may be volatile, and purchasers of our ADSs could incur substantial losses.

The market price for our ADSs may be volatile. The stock market in general and the market for biopharmaceutical companies in particular have experienced extreme volatility that has often been unrelated to the operating performance of particular companies. In particular, our share price in Paris has fluctuated from a 52-week high of €19.70 to a low of €5.60 as of October 19, 2023. As a result of this volatility, investors may not

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be able to sell their ADSs at or above the price originally paid for the security. The market price for our ADSs and ordinary shares may be influenced by many factors, including:

These and other market and industry factors may cause the market price and demand for our ADSs to fluctuate substantially, regardless of our actual operating performance, which may limit or prevent investors from readily selling their ADSs and may otherwise negatively affect the liquidity of the trading market for our ADSs.

If securities or industry analysts do not publish research or publish inaccurate or unfavorable research about our business, the price of our ADSs and their trading volume could decline.

The trading market for our ADSs depends in part on the research and reports that securities or industry analysts publish about us or our business. If no or few securities or industry analysts cover our company, the trading price for our ADSs would be negatively impacted. If one or more of the analysts who covers us downgrades our equity securities or publishes incorrect or unfavorable research about our business, the price of our ADSs would likely decline. If one or more of these analysts ceases coverage of our company or fails to publish reports on us regularly, or downgrades our securities, demand for our ADSs could decrease, which could cause the price of our ADSs or their trading volume to decline.

The requirements of being a U.S. public company may strain our resources and divert management’s attention.

We are required to comply with various corporate governance and financial reporting requirements under the Sarbanes-Oxley Act, the Exchange Act, and the rules and regulations adopted by the SEC and the Public Company Accounting Oversight Board. Further, compliance with various regulatory reporting requires significant commitments of time from our management and our directors, which reduces the time available for the performance of their other responsibilities. Our failure to track and comply with the various rules may materially adversely affect our reputation, ability to obtain the necessary certifications to financial statements, lead to additional regulatory enforcement actions, and could adversely affect the value of our ordinary shares or ADSs.

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After the completion of the offering, we may be at an increased risk of securities class action litigation.

Historically, securities class action litigation has often been brought against a company following a decline in the market price of its securities. This risk is especially relevant for us because biotechnology and biopharmaceutical companies have experienced significant share price volatility in recent years. If we were to be sued, it could result in substantial costs, which could be insufficiently covered by insurance, and a diversion of management’s attention and resources, which could harm our business.

We do not currently intend to pay dividends on our securities and, consequently, your ability to achieve a return on your investment will depend on appreciation in the price of the ordinary shares and our ADSs. In addition, French law may limit the amount of dividends we are able to distribute.

We have never declared or paid any cash dividends on our ordinary shares and do not currently intend to do so for the foreseeable future. We currently intend to invest our future earnings, if any, to fund our growth. Therefore, you are not likely to receive any dividends on your ADSs for the foreseeable future and the success of an investment in ADSs will depend upon any future appreciation in its value. Consequently, investors may need to sell all or part of their holdings of ADSs after price appreciation, which may never occur, as the only way to realize any future gains on their investment. There is no guarantee that the ADSs will appreciate in value or even maintain the price at which our shareholders have purchased them. Investors seeking cash dividends should not purchase our ADSs. Furthermore, certain of our debt instruments restrict the payment of dividends or require consent to pay dividends. See “Dividend Policy.”

Further, under French law, the determination of whether we have been sufficiently profitable to pay dividends is made on the basis of our statutory financial statements prepared and presented in accordance with accounting standards applicable in France. In addition, payment of dividends may subject us to additional taxes under French law. Therefore, we may be more restricted in our ability to declare dividends than companies not based in France.

In addition, exchange rate fluctuations may affect the amount of euros that we are able to distribute, and the amount in U.S. dollars that our shareholders receive upon the payment of cash dividends or other distributions we declare and pay in euros, if any. These factors could harm the value of our ADSs, and, in turn, the U.S. dollar proceeds that holders receive from the sale of our ADSs.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus contains forward-looking statements that involve substantial risks and uncertainties. The forward-looking statements are contained principally in the sections titled “Prospectus Summary” “Risk Factors” “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and “Business” but are also contained elsewhere in this prospectus. In some cases, you can identify forward-looking statements by the words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “future,” “goals,” “intend,” “likely,” “may,” “might,” “ongoing,” “objective,” “plan,” “potential,” “predict,” “project,” “seek,” “should,” “strategy,” “will” and “would” or the negative of these terms, or other comparable terminology intended to identify statements about the future. These statements involve known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance or achievements to be materially different from the information expressed or implied by these forward-looking statements. Although we believe that we have a reasonable basis for each forward-looking statement contained in this prospectus, we caution you that these statements are based on a combination of facts and factors currently known by us and our expectations of the future, about which we cannot be certain. Forward-looking statements include but are not limited to statements about:

You should refer to the “Risk Factors” section of this prospectus for a discussion of important factors that may cause our actual results to differ materially from those expressed or implied by our forward-looking

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statements. The Private Securities Litigation Reform Act of 1995 and Section 27A of the Securities Act, do not protect any forward-looking statements that we make in connection with the global offering. The forward-looking statements and opinions contained in this prospectus are based upon information available to us as of the date of this prospectus and, while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. As a result of these factors, we cannot assure you that the forward-looking statements in this prospectus will prove to be accurate. Furthermore, if our forward-looking statements prove to be inaccurate, the inaccuracy may be material. In light of the significant uncertainties in these forward-looking statements, you should not regard these statements as a representation or warranty by us or any other person that we will achieve our objectives and plans in any specified time frame, or at all. These statements are inherently uncertain and investors are cautioned not to unduly rely upon these statements. We undertake no obligation to publicly update any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by-law.

This prospectus also contains certain data and information that we obtained from various government and private publications. Statistical data in these publications also include projections based on a number of assumptions. Our industry may not grow at the rate projected by market data or at all. Failure of this market to grow at the projected rate may have a material and adverse effect on our business and the market price of our ordinary shares (including ordinary shares in the form of ADSs). Furthermore, if any one or more of the assumptions underlying the market data are later found to be incorrect, actual results may differ from the projections based on these assumptions. You should not place undue reliance on this data.

In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this prospectus, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete. Our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and investors are cautioned not to unduly rely upon these statements.

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USE OF PROCEEDS

We estimate that we will receive net proceeds from the global offering of approximately €201.1 million ($212.2 million) at the initial offering price of €10.9864 per ordinary share ($11.60 per ADS), after deducting the underwriting commissions and estimated offering expenses payable by us, and assuming no exercise of the underwriters’ option to purchase additional ordinary shares (which may be in the form of ADSs). If the underwriters exercise in full their option to purchase additional ordinary shares (which may be in the form of ADSs) in the global offering, we estimate that we will receive net proceeds from the offering of approximately €232.2 million ($245.1 million) at the initial offering price of €10.9864 per ordinary share ($11.60 per ADS), after deducting the underwriting commissions and estimated offering expenses payable by us.

We intend to use the net proceeds from the global offering as follows:

We may also use a portion of the remaining net proceeds and our existing cash and cash equivalents to in-license, acquire, or invest in complementary businesses, technologies, products or assets. However, we have no current commitments or obligations to do so.

We believe that the anticipated net proceeds from this offering, together with our current cash and cash equivalents, will allow us to finance our operations through (i) the announcement of our top-line data from our Phase 3 ABTECT-1 and ABTECT-2 induction trials for UC and (ii) the announcement of our top-line data from our Phase 2a induction trial for CD.

This expected use of net proceeds from the global offering represents our intentions based upon our current plans and business conditions, which could change in the future as our plans and business conditions evolve. The amounts and timing of our actual expenditures may vary significantly depending on numerous factors, including the progress of our development, the status of and results from clinical trials, as well as any collaborations that we may enter into with third parties for our drug candidates, and any unforeseen cash needs. As a result, our management retains broad discretion over the allocation of the net proceeds from the global offering.

Pending our use of the net proceeds from the global offering, we intend to invest the net proceeds in a variety of capital preservation investments, including short-term, investment-grade, interest-bearing instruments.

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DIVIDEND POLICY

We have never declared or paid any cash dividends on our ordinary shares. We do not have any present plan to pay any cash dividends on our equity securities in the foreseeable future after the global offering. We currently intend to retain all of our available funds and any future earnings to operate and expand our business. For as long as any amount is outstanding under the Kreos / Claret Financing, we are not permitted to declare or make any dividend without consent from KC or Claret. In the event a dividend is made or declared, the terms and conditions of the OCABSAs and BSAs issued to KC and Claret and the terms and conditions of the convertible notes issued to Heights provide for an adjustment of the conversion ratio. We do not anticipate paying cash dividends on our equity securities in the foreseeable future and intend to retain all available funds and any future earnings for use in the operation and expansion of our business, given our state of development.

Subject to the requirements of French law and our by-laws, dividends may only be distributed from our distributable profits, plus any amount held in our available reserves, which are those reserves other than the legal and statutory reserves and the revaluation surplus. See “Description of Share Capital” for further details on the limitations on our ability to declare and pay dividends.

If we pay any dividends, we will pay our ADS holders to the same extent as holders of our ordinary shares, subject to the terms of the deposit agreement, including deduction in respect of the fees and expenses payable thereunder. See “Description of American Depositary Shares” for further information. Cash dividends on our ordinary shares, if any, will be paid in euros and converted into U.S. dollars with respect to ADSs, as provided in the deposit agreement.

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CAPITALIZATION

The table below sets forth our cash and cash equivalents and total capitalization as of June 30, 2023 on:

The Kreos / Claret Financing and the Heights Convertible Notes consist of elements that need to be fair valued under IFRS. We have performed a preliminary valuation to estimate the fair value for the purposes of preparing the capitalization table and therefore such figures may be subject to further adjustments. The table should be read in conjunction with the information contained in “Use of Proceeds,” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” as well as our financial statements and the related notes included elsewhere in this prospectus.

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Unless otherwise indicated, the number of ordinary shares (including ordinary shares in the form of ADSs) that will be outstanding after the global offering is based on 42,547,568 ordinary shares outstanding as of June 30, 2023 and excludes:

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For additional details relating to the Kreos / Claret Financing and the Heights Financing, see “Business—Key Collaborations and Partners—Financing Arrangements.” References to outstanding ordinary shares included in this prospectus include 11,487 treasury shares issued by us as of June 30, 2023. Except as otherwise noted, the information in this prospectus assumes no exercise by the underwriters of their option to purchase 3,048,825 additional ADS and/or ordinary shares in the global offering and no exercise of share warrants (BSA), founder’s share warrants (BCE) or vesting of free shares (AGA) or other equity awards subsequent to June 30, 2023.

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DILUTION

If you invest in our ordinary shares or ADSs in the global offering, your ownership interest will be diluted to the extent of the difference between the public offering price per ordinary share or ADS paid by purchasers in the global offering and the pro forma as adjusted net tangible book value per ordinary share or ADS, as applicable, after completion of the global offering.

Our net tangible book value as of June 30, 2023 was €55.5 million ($60.6 million), or €1.30 per ordinary share ($1.42 per ADS), based on the exchange rate of €1.00 = $1.0919 as of June 30, 2023. Net tangible book value per ordinary share is determined by dividing (i) our total assets less our intangible assets, our goodwill and our total liabilities by (ii) the number of ordinary shares outstanding as of June 30, 2023 or 42,547,568 ordinary shares.

Our pro forma net tangible book value as of June 30, 2023 was €58.4 million ($63.8 million), or €1.37 per ordinary share ($1.50 per ADS), based on the exchange rate of €1.00 = $1.0919 as of June 30, 2023. Pro forma net tangible book value per ordinary share is our net tangible book value as of June 30, 2023, after giving effect to the (i) issuance of the Kreos / Claret OCABSA in the amount of €25.0 million in gross proceeds, (ii) issuance of the Heights Convertible Notes (based on a valuation as of August 24, 2023) in the amount of €35.0 million in gross proceeds and (iii) repayments of all outstanding amounts that remained due under the First KC Agreement, the Second KC Agreement and the OCEANE bonds in the amount of €34.2 million (outstanding as of June 30, 2023). The Kreos / Claret Financing and the Heights Convertible Notes consist of elements that need to be fair valued under IFRS. We have performed a preliminary valuation to estimate the fair value for the purposes of preparing the pro forma as adjusted figures in the table below and therefore such figures may be subject to further adjustments.

After giving effect to the receipt of the estimated net proceeds from our sale of 20,325,500 ordinary shares (which may be in the form of ADSs) in the global offering, at the initial offering price of €10.9864 per ordinary share ($11.60 per ADS), and after deducting the underwriting commissions and estimated offering expenses payable by us, our pro forma as adjusted net tangible book value as of June 30, 2023 would have been €259.5 million ($276.0 million), or €4.13 per ordinary share ($4.39 per ADS). This represents an immediate increase in pro forma net tangible book value of €2.75 per ordinary share ($2.89 per ADS) to existing shareholders and an immediate dilution in net tangible book value of €6.86 per ordinary share ($7.21 per ADS) to new investors.

The following table illustrates this dilution on a per ordinary share and per ADS basis:

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If the underwriters exercise their option to purchase 3,048,825 additional ordinary shares and/or ADSs in full, the pro forma as adjusted net tangible book value per ordinary share after the offering would be €4.41 per ordinary share ($4.69 per ADS), the increase in the pro forma as adjusted net tangible book value to existing shareholders would be €0.28 per ordinary share ($0.30 per ADS), and the dilution to new investors participating in the offering would be €6.58 per ordinary share ($6.91 per ADS).

The following table sets forth, as of June 30, 2023, the number of ordinary shares purchased from us, the total consideration paid to us and the average price per ordinary share paid by existing shareholders and to be paid by new investors participating in the global offering, at the initial offering price of €10.9864 per ordinary share ($11.60 per ADS), after deducting the underwriting commissions and estimated offering expenses payable by us.

The table above assumes no exercise of the underwriters’ option to purchase 3,048,825 additional ADS and/or ordinary shares in the global offering and no exercise of share warrants (BSA), founder’s share warrants (BCE) or vesting of free shares (AGA) or other equity awards subsequent to June 30, 2023. If the underwriters exercise their option to purchase 3,048,825 additional ADSs and/or ordinary shares (which may be in the form of ADSs) in full, the number of ordinary shares held by the existing shareholders after the global offering would be reduced to 64.5% of the total number of ordinary shares (including ordinary shares represented by ADSs) outstanding after the global offering, and the number of shares held by new investors participating in the global offering (including ordinary shares represented by ADSs) would increase to 35.5% of the total number of ordinary shares outstanding after the global offering (including ordinary shares represented by ADSs).

Unless otherwise indicated, the number of ordinary shares (including ordinary shares in the form of ADSs) that will be outstanding after the global offering is based on 42,547,568 ordinary shares outstanding as of June 30, 2023 and excludes:

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For additional details relating to the Kreos / Claret Financing and the Heights Financing, see “Business—Key Collaborations and Partners—Financing Arrangements.” References to outstanding ordinary shares included in this prospectus include 11,487 treasury shares issued by us as of June 30, 2023. Except as otherwise noted, the information in this prospectus assumes no exercise by the underwriters of their option to purchase 3,048,825 additional ADS and/or ordinary shares in the global offering and no exercise of share warrants (BSA), founder’s share warrants (BCE) or vesting of free shares (AGA) or other equity awards subsequent to June 30, 2023.

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ENFORCEMENT OF CIVIL LIABILITIES

We are a société anonyme, organized under the laws of France. The majority of our directors and officers are residents of countries other than the United States, and the majority of our assets are located outside of the United States. We have appointed an agent for service of process in the United States.

Accordingly, U.S. investors may find it difficult and may be unable:

In addition, actions in the United States under U.S. federal securities laws could be affected under certain circumstances by French Law No. 68-678 of July 26, 1968, as amended by French Law No. 80-538 of July 16, 1980 and French Ordinance No. 2000-916 of September 19, 2000 (relating to the communication of documents and information of an economic, commercial, industrial, financial or technical nature to foreign authorities or persons), which may preclude or restrict the obtaining of evidence in France or from French persons in connection with those actions.

Nevertheless, a final judgment for the payment of money rendered by any federal or state court in the United States based on civil liability, whether or not predicated solely upon the U.S. federal securities laws, would be recognized and enforced in France provided that a French judge considers that this judgment meets the French legal requirements concerning the recognition and the enforcement of foreign judgments and is capable of being immediately enforced in the United States. A French court is therefore likely to grant the enforcement of a foreign judgment without a review of the merits of the underlying claim, only if: (i) that judgment does not contravene international public order and public policy of France, both pertaining to the merits and to the standards of due process; and (ii) the dispute is clearly connected to the territory of the court which rendered the judgement, and French courts did not have exclusive jurisdiction on the matter. The French court would also require that the U.S. judgment is not tainted with fraud and is not incompatible with a judgment rendered by a French court in the same matter, or with an earlier judgment rendered by a foreign court which has become effective in France in the same matter.

In addition, French law guarantees full compensation for the harm suffered but is limited to the actual damages, so that the victim does not suffer or benefit from the situation. Such system excludes damages such as, but not limited to, punitive and exemplary damages. Therefore, there is some uncertainty as to whether a foreign judgement awarding punitive and exemplary damages well above actual damages would be granted enforcement in France.

As a result, the enforcement, by U.S. investors, of any judgments obtained in U.S. courts in civil and commercial matters, including judgments under the U.S. federal securities law against us or members of our Board, officers or certain experts named herein who are residents of France or countries other than the United States would be subject to the above conditions.

Finally, there may be doubt as to whether a French court would impose civil liability on us, the members of our Board, our officers or certain experts named herein in an original action predicated solely upon the U.S. federal securities laws brought in a court of competent jurisdiction in France against us or such members, officers or experts, respectively.

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MANAGEMENT’S DISCUSSION AND ANALYSIS OF

FINANCIAL CONDITION AND RESULTS OF OPERATIONS

You should read the following discussion of our financial condition and results of operations in conjunction with our financial statements and the related notes thereto included elsewhere in this prospectus. In addition to historical information, the following discussion and analysis contains forward-looking statements that reflect our plans, estimates and beliefs. Our actual results and the timing of events could differ materially from those anticipated in the forward-looking statements. Factors that could cause or contribute to these differences include those discussed below and elsewhere in this prospectus, particularly in the sections titled “Risk Factors” and “Cautionary Note Regarding Forward-Looking Statements.”

Overview

We are a clinical-stage biotechnology company focused on developing therapeutics that harness the body’s natural regulatory mechanisms to modulate the immune response in patients with chronic inflammatory diseases. We are currently evaluating our lead drug candidate, obefazimod, in Phase 3 clinical trials for the treatment of adults with moderately to severely active ulcerative colitis (“UC”). We are also in the planning stages of initiating a Phase 2a clinical trial of obefazimod in patients with Crohn’s disease (“CD”), as well as evaluating other potential inflammatory indications.

We focus on indications where existing treatments have left patients with significant unmet needs, and where we believe our investigational agents have the potential to be meaningfully differentiated from currently available therapies. The indications we target have substantial populations and represent large commercial opportunities, pending regulatory approvals and successful commercialization. Our initial focus is on inflammatory bowel diseases (“IBD”), chronic conditions involving inflammation of the gastrointestinal tract, of which the two most common forms are UC and CD. As of 2022, an aggregate of approximately 2.9 million patients across the United States, EU4 (France, Germany, Italy and Spain), the United Kingdom and Japan suffered from IBD, with 1.5 million of these patients in the United States alone.

We believe our lead drug candidate, obefazimod, is differentiated from competing approaches for the treatment of IBD via its novel mechanism of action. Obefazimod was demonstrated to specifically enhance the expression of a single micro-RNA, miR-124, which plays a critical role in the regulation of the inflammatory response. In the context of inflammation, miR-124 is a natural regulator of the inflammatory response, controlling progression of inflammation and restoring homeostasis of the immune system, without causing broader immunosuppression. In contrast to currently available advanced therapies, prescribed post-conventional therapies, some of which target only a single cytokine or pathway, miR-124 modulates the expression of several key cytokines and pathways. Modulating multiple inflammatory pathways simultaneously may lead to more durability of efficacy results over the long-term, which is critical in lifelong conditions such as IBD, potentially differentiating obefazimod from currently available IBD treatments.

Our team is comprised of industry leaders in the fields of biology, data analytics and drug development, as well as scientific experts in chronic inflammatory diseases, including IBD. We are led by Marc de Garidel, our Chief Executive Officer, who has more than 40 years of experience in the pharmaceutical and biotechnology sector. Collectively, our team has decades of experience and a proven track record of advancing compounds into and through clinical development and commercialization, including at the following organizations: Amgen, Arena Pharmaceuticals, AstraZeneca, BioNTech, Boehringer Ingelheim, Eli Lilly, Genentech/Roche, Guerbet, Ipsen Pharmaceuticals, J&J, Pfizer, Sanofi, Sanofi-Pasteur and Shire/Takeda.

We were incorporated as a société anonyme on December 4, 2013 and, in 2014, we acquired Splicos, Wittycell and Zophis by means of a universal transfer of assets and liabilities (Transmission Universelle du Patrimoine (“TUP”)). We have been listed on Euronext Paris since June 26, 2015.

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On April 1, 2022, we acquired 100% of the share capital of Prosynergia S.à.r.L (“Prosynergia”), a Luxembourg-based biotechnology company, with the aim of strengthening our research and development portfolio, for an amount of €3.25 million. On December 12, 2022, we completed the merger with Prosynergia through a TUP and all of Prosynergia’s assets and liabilities were transferred to us. Following the merger, Prosynergia was dissolved.

On March 20, 2023, our United States-based subsidiary Abivax LLC (the “Subsidiary”) was formed as a limited liability company under the laws of the State of Delaware. The Subsidiary hosts our operations in the United States. We have prepared unaudited interim condensed consolidated financial statements as of and for the six-month period ended June 30, 2023. As of June 30, 2023, the Subsidiary’s contribution to our consolidated results of operations was a net operating loss of €0.6 million.

Since our inception in 2013, we have devoted substantially all of our efforts to organizing and staffing our company, business planning, raising capital, establishing our intellectual property portfolio, acquiring or discovering drug candidates, research and development activities for obefazimod and other compounds, establishing arrangements with third parties for the manufacture of our drug candidates and component materials, and providing general and administrative support for these operations. We do not have any products approved for sale and have not generated any revenue from product sales or otherwise. We do not expect to generate significant revenue from product sales or royalties unless and until our drug candidates are approved for marketing and successfully commercialized.

We have incurred significant operating losses since inception, and we expect to continue to incur significant expenses and operating losses for the foreseeable future. Our ability to generate product revenue sufficient to achieve profitability will depend heavily on the successful development and eventual commercialization of obefazimod and any future drug candidates. For the six-month periods ended June 30, 2023 and 2022 and the years ended December 31, 2022 and 2021, we reported net losses of €52.0 million, €21.2 million, €60.7 million and €42.5 million, respectively. As of June 30, 2023, we carried forward accumulated tax losses of €355.4 million. We expect to continue to incur net operating losses for at least the next several years, and we do not anticipate achieving profitability in the future unless we obtain regulatory approvals necessary to commercialize obefazimod and any additional drug that we may pursue in the future. We expect that our research and development expenses, general and administrative expenses, and capital expenditures will increase substantially in connection with our ongoing activities, particularly if and as we:

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Our net losses may fluctuate significantly from period to period, depending on the timing of expenditures related to our research and development activities.

We will not generate revenue from product sales unless and until we successfully complete clinical development and obtain regulatory approval for a drug candidate. In particular, following the issuance of royalty certificates in September 2022 and other royalties that may become payable under our royalty agreements, the payment of royalties in the event of commercialization of obefazimod will result in a decrease in cash flows generated by sales of the product, which could have an unfavorable impact on our financial position, particularly at the beginning of the commercialization phase. In addition, if we obtain regulatory approval for a drug candidate and do not enter into a third-party commercialization partnership, we expect to incur significant expenses related to developing our commercialization capability to support product sales, marketing, manufacturing and distribution activities.

As a result, we will need substantial additional funding to support our continuing operations and pursue our growth strategy. Until such time as we can generate significant revenue from product sales, if ever, we expect to finance our operations through equity offerings, debt financings or other capital sources, which could include collaborations, strategic alliances or additional licensing arrangements. We may be unable to raise additional funds or enter into such arrangements when needed, on favorable terms, or at all. Our failure to raise capital or enter into such agreements as, and when, needed, could have a material adverse effect on our business, results of operations and financial condition, including requiring us to have to delay, reduce or eliminate product development or future commercialization efforts. The amount and timing of our future funding requirements will depend on many factors, including the successful advancement of obefazimod or any future drug candidates. Our ability to raise additional funds may also be adversely impacted by potential worsening global economic conditions and disruptions to and volatility in the credit and financial markets in the United States and worldwide, such as those resulting from the ongoing war in Ukraine.

Because of the numerous risks and uncertainties associated with development of treatment of chronic inflammatory diseases, we are unable to predict the timing or amount of increased expenses or when or if we will be able to achieve or maintain profitability. Even if we are able to generate product sales, we may not become profitable. If we fail to become profitable or are unable to sustain profitability on a continuing basis, then we may be unable to continue our operations at planned levels and be forced to reduce or terminate our operations.

Since inception, we have financed our operations through the issuance of ordinary shares with gross aggregate proceeds of €333.9 million, of which €130 million of gross proceeds were from offerings of our ordinary shares on Euronext Paris in February 2023, bank borrowings and structured loans for €125.0 million, reimbursements of CIR in an amount of €26.6 million, subsidies received from Bpifrance (including €13.5 million of subsidies and €6.6 million of conditional advances) and royalty certificates in an amount of €2.9 million.

As of June 30, 2023, we had cash and cash equivalents of €114.4 million. We believe that based on our current clinical plan and on our anticipated net proceeds from this offering, together with (a) our existing cash and cash equivalents of €114.4 million as of June 30, 2023, (b) the net proceeds of the August 2023 drawdown of the first tranches of the Kreos / Claret Financing and the Heights Financing, collectively amounting to €27.2 million (net of repayments of all outstanding amounts that remained due under the First KC Agreement,

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the Second KC Agreement and the OCEANE bonds), (c) the anticipated net proceeds from the drawdown of the second tranche of the Kreos / Claret Financing, amounting to €25 million (which is a portion of the total available drawdown of €65 million from the Kreos / Claret Financing and the Heights Financing) and (d) the expected Research Tax Credit (CIR) reimbursements would enable us to fund our operations through the fourth quarter of 2025. Under these assumptions and based on our current clinical plan, we would have sufficient funds to finance our operations through (i) the announcement of our top-line data from the Phase 3 ABTECT-1 and ABTECT-2 induction trials for UC and (ii) the announcement of our top-line data from the Phase 2a induction trial for CD.

If we further draw down on the third tranche of the Kreos / Claret Financing, amounting to €25 million and the second tranche of the Heights Financing amounting to €40 million, we expect to have sufficient funds to finance our operations through the first quarter of 2026. Under these assumptions and based on our current clinical plan, we would have sufficient funds to finance our operations through the announcement of our top-line data from the Phase 3 ABTECT maintenance trial for UC. For additional details relating to the Kreos / Claret Financing and the Heights Financing, see “Business—Key Collaborations and Partners—Financing Arrangements.”

This takes into account our assumption that R&D expenditure will be substantially increased in 2023 driven by the progression of the Phase 3 clinical trials of obefazimod, which started enrollment of patients with moderately to severely active UC in October 2022. We have based this estimate on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we expect. We anticipate that we will require additional capital as we seek regulatory approval of our drug candidates. We intend to assess and plan for any such funding requirements and aim to regularly update the market on our financing need projections. See “—Liquidity and Capital Resources.”

Beyond that date, our ability to fund operations will depend upon our ability to raise additional capital from existing and/or new specialized investors and/or debt from lenders. In particular, we may consider carrying out one or more capital increases, entering into loan agreements or issuing bonds and entering into regional licensing agreements for obefazimod, specifically targeting third-party partners in Asia. Our operating plans may change as a result of a variety of factors, and we may need to seek additional funds sooner than planned. In any event, we will require additional capital to pursue preclinical and clinical activities, obtain regulatory approval for and commercialize our drug candidates. If sufficient funds on acceptable terms are not available when needed, or at all, we could be required to significantly reduce our operating expenses and delay, reduce the scope of, or eliminate one or more of our development programs. See the subsection titled “—Liquidity and Capital Resources.”

Presentation of Financial Information

Our audited financial statements as of, and for the years ended, December 31, 2022 and 2021 were prepared in accordance with International Financial Reporting Standards (“IFRS”), as issued by the International Accounting Standards Board (“IASB”).

Our unaudited interim condensed consolidated financial statements as of June 30, 2023, and for the six-month periods ended June 30, 2023 and 2022 were prepared in accordance with IAS 34, Interim Financial Reporting, the standard of IFRS applicable to interim financial statements.

Principal Factors Affecting Our Results of Operations

The following factors have affected, and we expect will continue to affect, our results of operations.

Research and Development Activities

Research and development activities are central to our business. Since our inception, most of our resources have been allocated to research and development and it accounts for the majority of our operating expenses. For

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the year ended December 31, 2022, research and development expenses accounted for 87%, excluding goodwill impairment loss, of our total operating expenses, as compared to 90% for the year ended December 31, 2021. For the six-month period ended June 30, 2023, research and development expenses accounted for 83% of our total operating expenses, as compared to 87% (excluding goodwill impairment loss) for the six-month period ended June 30, 2022. Drug candidates in later stages of clinical development generally have higher development costs than those in earlier stages of clinical development, primarily due to the increased size and duration of later-stage clinical trials. Accordingly, we expect that our research and development expenses will increase in the foreseeable future as we seek to advance the development of our drug candidates. The successful development of our drug candidates remains highly uncertain.

At this time, we cannot accurately determine or estimate the nature, timing and costs of the research and development activities that will be necessary to complete the remainder of the development of obefazimod, and we may never succeed in obtaining regulatory approval for obefazimod or any future drug candidates we may develop. The duration, costs and timing of clinical trials and the development of our drug candidates will depend on numerous risks and uncertainties associated with clinical development, including risks and uncertainties related to:

A change in the outcome of any of these variables with respect to the development of any of our drug candidates could significantly change the costs and timing associated with the development of that drug candidate. The actual probability of success for our drug candidates will be affected by a variety of factors, including the safety and efficacy of our drug candidates, investment in our clinical programs, manufacturing capability and competition with other products and drug candidates. As a result of these variables, we are unable to determine the duration and completion costs of our research and development projects or when and to what extent we may generate revenue from the commercialization and sale of our drug candidates.

Regulatory Approval and Market Acceptance of our Drug Candidates

We may never succeed in achieving regulatory approval for any of our drug candidates. We may obtain unexpected results from our clinical trials. We may elect to discontinue, delay or modify clinical trials of some

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drug candidates or focus on others. A change in the outcome of any of these factors with respect to the development of drug candidates that we are developing could result in a significant change in the costs and timing associated with the development of such drug candidates. For example, if the EMA or the FDA or other regulatory authority were to require us to conduct non-clinical studies and clinical trials beyond those that we currently anticipate will be required for the completion of clinical development, or if we experience significant delays in enrollment in any clinical trials, we could be required to spend significant additional financial resources and time on the completion of clinical development.

Equity and Debt Financing

At this stage, we have not generated any revenue from sales of products or otherwise, and we do not expect to do so unless and until we successfully complete development of, obtain marketing approval for, and successfully commercialize, one or more of our drug candidates. Until such time that we can generate substantial revenue from sales of products, if ever, we expect to finance our operating activities through a combination of equity offerings, debt financings and government or other third-party funding. However, we may be unable to raise additional funds or enter into such arrangements when needed on favorable terms, or at all, which would have a negative impact on our financial condition and could force us to delay, limit, reduce or terminate our development programs or commercialization efforts or grant to others the rights to develop or market drug candidates that we would otherwise prefer to develop and market ourselves. Failure to receive additional funding could cause us to cease operations, in part or in full.

Acquisition of Prosynergia

On April 1, 2022, we acquired 100% of the share capital of Prosynergia with the aim of strengthening our research and development portfolio, for an amount of €3.25 million. On December 12, 2022, we completed the merger with Prosynergia through a TUP and all of Prosynergia’s assets and liabilities were transferred to us. Following the merger, Prosynergia was dissolved. Accordingly, as Prosynergia was dissolved in December 2022, we did not prepare consolidated financial statements as of December 31, 2022.

Impact of the Ukraine/Russia Hostilities on our Business

In February 2022, Russia invaded Ukraine. The conflict has already had major implications for the global economy and the rate of inflation, particularly in relation to the supply of energy, raw materials and food products. It has also caused intense volatility on the financial markets, something that is still ongoing at the reporting date and has pushed down stock market prices the world over. The global scale of this conflict cannot be predicted at this stage. We, therefore, cannot rule out an adverse impact of this conflict on our business, including in terms of access to raw materials, logistics, the performance of clinical trials and in relation to any future financing we may seek.

The Phase 2b maintenance trial of obefazimod in moderately to severely active UC is our only clinical trial currently in progress in Ukraine. We have, however, terminated a few trial sites since the Russia/Ukraine war began. The 12-month assessment was carried out in all the Ukrainian patients before the war broke out and these patients are therefore included in the one-year maintenance results that were reported on April 6, 2022. Ukrainian patients who completed the two-year Phase 2b maintenance trial have been transitioned to the long-term safety and efficacy trial that is still on-going. None of these sites are located in the Crimea Region of Ukraine, the so-called Donetsk People’s Republic, or the so-called Luhansk People’s Republic. We are also evaluating the possibility to include a few Ukrainian sites in the western part of Ukraine in the ABTECT Phase 3 clinical trials.

Together with our CRO, we are making considerable efforts to ensure the follow-up of patients who are unable to come to the study centers. Monitoring takes place through a remote monitoring system that was established and used successfully during the COVID-19 pandemic.

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Components of Our Results of Operations

The following discussion sets forth certain components of our results of operations, as well as factors that impact those items.

Total Operating Income

We have not generated any revenue from product sales or from other sources, and we do not expect to generate any revenue from the sale of products or otherwise, even if approved, in the near future. Our ability to generate revenue in the future, if ever, will depend almost entirely on our ability to successfully develop, obtain regulatory approval for, and then commercialize our drug candidates or conclude a partnering business development agreement within our product portfolio.

Other Operating Income

Other operating income comprises subsidies in the form of non-refundable subsidies from Bpifrance and CIR, each as described below. Subsidies that are upfront payments are presented as deferred income and recognized as other income for the amount of the expenses incurred as part of the research program to which the subsidy relates. Subsidies that are received either as compensation for expenses or losses already incurred, or for our immediate financial support without associated future costs, are recognized as other income when there we have reasonable assurance that the subsidies will be received.

Subsidies are non-repayable grants received by us. They are recognized in the financial statements in the period in which the related expenses are incurred when there is reasonable assurance that the subsidies will be received and that we will comply with their conditions. We have received various subsidies and other assistance from Bpifrance since our creation. The funds are intended to finance our operations or specific projects. See “—Liquidity and Capital Resources—Sources of Liquidity—Bpifrance – Conditional Advances and Subsidies.”

The French tax authorities grant a CIR to companies to encourage technical and scientific research by French companies. Companies demonstrating that they have incurred research expenses that meet the required criteria, including research expenses located in France or certain other European countries, receive a tax credit that can be used against the payment of the corporate tax due for the fiscal year in which the expenses were incurred and during the next three fiscal years. Companies may receive cash reimbursement for any excess portion.

We apply for the CIR for research expenses incurred in each fiscal year and recognize the amounts claimed in the same fiscal year. As we meet the EU definition of a small and medium-sized enterprise (“SME”), we are eligible for payment in cash of our CIR in the year following the request for reimbursement, which corresponds to the period after which we incurred the eligible costs.

We have concluded that the CIR meets the definition of a government grant as defined in IAS 20, Accounting for Government Grants and Disclosure of Government Assistance, and, as a result, they have been classified as “Other income” within operating income in our statements of operations.

We received the CIR for 2021 in October 2022 and we expect to receive the CIR for 2022 in the second half of 2023, in each case under the community tax rules for SMEs and in compliance with the current regulations. The CIRs we are granted may be subject to audit by the French tax authorities.

Total Operating Expenses

Our operating expenses consist of research and development expenses and general and administrative expenses.

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Research and Development Expenses

Our research and development expenses consist primarily of the following items:

We allocate these costs by drug candidate and by therapeutic indication. Costs that are not directly attributable to a specific therapeutic indication are included under the category of transversal activities, which include the following:

Our research and development expenses may vary significantly in the future based on factors, such as:

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A change in the outcome of any of these variables with respect to the development of any of our drug candidates could significantly change the costs and timing associated with the development of that drug candidate. We may never succeed in obtaining regulatory approval for any of our drug candidates. We may obtain unexpected results from our non-clinical studies and future clinical trials.

General and Administrative Expenses

General and administrative expenses primarily comprise personnel-related expenses, including salaries, benefits and share-based compensation expenses, for personnel other than employees engaged in research and development activities. General and administrative expenses also include fees for professional services, mainly related to audit and legal services, consulting costs, communications and travel costs, allocated expenses for facility costs, including rent, utilities and maintenance, directors’ attendance fees, and insurance costs.

We expect our general and administrative expenses will increase in the future as we increase our headcount to support our continued research activities and the development of our product candidates, potential commercialization efforts and increased costs associated with being a public company in the United States. These increases will likely include additional costs related to the hiring of new personnel, including higher stock-based compensation expenses, and fees to outside consultants, as well as other expenses. We also anticipate that we will incur significantly increased accounting, audit, legal, regulatory, compliance and director and officer insurance costs as well as investor and public relations expenses associated with operating as a public company both in France and in the United States.

Financial Income/(Loss)

Financial income/(loss) includes the amortized cost of the conditional advances, convertible notes, non-convertible bonds, royalty certificates, fair value adjustments on financial instruments, and other financial income and expenses such as the unwinding effect of CRO advances. We expect to incur additional financial expenses related to financing agreements or similar transactions that we may enter into to finance our further development.

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Results of Operations

Comparison of Years Ended December 31, 2022 and 2021

The following table sets forth our results of operations for the years ended December 31, 2022 and 2021.