Abivax S.A.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16 UNDER THE

SECURITIES EXCHANGE ACT OF 1934

For the month of September 2026

Commission file number:001-41842

Abivax SA

(Exact name of Registrant as specified in its charter and translation of Registrant’s name into English)

7-11 boulevard Haussmann

75009 Paris, France

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-

F.

Form 20-F☒ Form 40-F☐

On September 21, 2026, Abivax SA (the "Registrant") announced its financial results as of and for the three andsix

months ended June 30, 2026 and issued a press release and its unaudited interim condensed consolidated financial

statements, copies of which are attached hereto as Exhibits 99.1 and 99.2, respectively, and incorporated herein by

reference.

Incorporation by Reference

This Report on Form 6-K, including Exhibits 99.1 and 99.2, except for the quotes contained therein, shall be deemed

to be incorporated by reference into the Registrant’s registration statements on Form F-3 (File Nos. 333-283336 and

333-288884) and Form S-8 (File Nos. 333-286069 and 333-294544) and to be part thereof from the date on which

this Report is filed, to the extent not superseded by documents or reports subsequently filed.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be

signed on its behalf by the undersigned, thereunto duly authorized.

Exhibit 99.2

Unaudited Interim Condensed Consolidated Financial Statements

TABLE OF CONTENTS

INTRODUCTION

Unless otherwise indicated or the context otherwise requires, “Abivax,” “the Company,” “the Group,” “we,”

“us” and “our” refer to Abivax SA and its consolidated subsidiary, taken as a whole.

“Abivax” and the Abivax logo and other trademarks or service marks of Abivax SA appearing in this half-year

report are the property of Abivax SA. Solely for convenience, the trademarks, service marks and trade names

referred to in this half-year report 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 half-year report 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.

This half-year report includes our unaudited interim condensed consolidated financial statements of financial

position as of June 30, 2026 and December 31, 2025 and the related unaudited condensed consolidated statements of

loss and comprehensive loss for each of the three- and six-month periods ended June 30, 2026 and June 30, 2025

and the unaudited condensed consolidated statements of cash flows and changes in shareholder's equity for the six-

month periods ended June 30, 2026 and June 30, 2025, prepared in accordance with International Financial

Reporting Standards ("IFRS") as issued by the International Accounting Standards Board ("IASB") and adopted by

the European Union ("EU") regulation n°1606/2022 of July 19, 2022. None of our financial statements were

prepared inaccordance 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 half-

year report 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. Throughout this half-year report, references to

"ADSs" mean American Depositary Shares ("ADSs") or ordinary shares represented by such ADSs, as the case may

be.

Special Note Regarding Forward-Looking Statements

This half-year report contains forward-looking statements within the meaning of Section 27A of the Securities

Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended ("Exchange Act"),

that are based on our management’s beliefs and assumptions and on information currently available to our

management. All statements other than present and historical facts and conditions contained in this half-year report,

including statements regardingour future results of operations and financial positions, business strategy, plans and

our objectives for future operations, are forward-looking statements. When used in this half-year report, the words

“anticipate,” “believe,” “can,” “could,” “estimate,” “expect,” “intend,” “is designed to,” “may,” “might,” “plan,”

“will,” “would,” “potential,” “predict,” “objective,” “should,” or the negative of these and similar expressions

identify forward-looking statements. Forward-looking statements include, but are not limited to, statements about:

•the prospects of attaining, maintaining and expanding marketing authorization for our lead drug candidate,

obefazimod;

•the potential attributes and clinical advantages ofobefazimod andour future drug candidates;

•the initiation, timing, progress and results of our preclinical and clinical trials (and those conducted by third

parties) and other research and development programs;

•the timing of the availability of data from our clinical trials, including our Phase 2b trial of obefazimod in

Crohn’s disease;

•the timing of and our ability to advance drug candidates through clinical development;

•the timing or likelihood of regulatory meetings and filings;

•the timing of and our ability to obtain and maintain regulatory approvals forobefazimod andany of our

future drug candidates;

•our ability to identify and develop new drug candidates from our preclinical studies;

•our ability to develop sales and marketing capabilities and transition into a commercial-stage company;

•the effects of increased competition as well as innovations by new and existing competitors in our industry;

•our ability to enter into strategic relationships or partnerships;

•our ability to obtain, maintain, protect and enforce our intellectual property rights and proprietary

technologies and to operate our business without infringing the intellectual property rights and proprietary

technology of third parties;

•our estimate of the period of time through which we anticipate our financial resources will be adequate to

support our operations;

•our estimates regarding expenses, future revenues, capital requirements and the need for additional

financing;

•the impact of government laws and regulations;

•our competitive position; and

•unfavorable conditions in our industry, the global economy or global supply chain, including financial and

credit market fluctuations, international trade relations, political turmoil, natural catastrophes, warfare (such

as the Russia-Ukraine war and the conflict in the Middle East), and terrorist attacks.

We encourage you to read and carefully consider all of the risk factors disclosed in our annual report on Form

20-F for the year ended December 31, 2025 filed with the Securities and Exchange Commission ("SEC") on March

23, 2026 (the "Annual Report") under the caption “Item 3.D—Risk Factors” for a more complete understanding of

the risks and uncertainties that we believe arematerial to our business, including important factors that may cause

our actual results to differ materially from those expressed or implied by our forward-looking statements. As a result

of these factors, we cannot assure you that the forward-looking statements in this document 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 forward-looking statements represent our plans, objectives, estimates, expectations and

intentions only as of the date of this filing. 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.

You should read this document and the documents that we reference herein completely and with the

understanding that our actual future results may be materially different from what we expect. We qualify all of our

forward-looking statements by these cautionary statements.

Rounding of Figures

Certain figures (including data expressed in thousands or millions of euros or dollars) and the percentages

presented in this half-year report have been rounded up or down. Accordingly, totals given may vary slightly from

those obtained by adding the rounded values of those same figures.

RISK FACTORS

The Company’s business faces significant risks. You should carefully consider all of the information set forth

in this document and in the Company’s other filings with the SEC, including the risk factors which the Company

faces and which are faced by the Company’s industry described in “Item 3.D—Risk Factors” of the Company’s

Annual Report on Form 20-F for the fiscal year ended December 31, 2025. Our risk factors have not changed

materially from those described in our Annual Report on Form 20-F. Our business, financial condition or results of

operations could be materially adversely affected by any of these risks.

OPERATING RESULTS

Overview

We are a clinical-stage biotechnology company focused on developing therapeutics that harness the body’s

natural regulatory mechanisms to stabilize the immune response in patients with chronic inflammatory diseases. Our

lead drug candidate, obefazimod, is currently being evaluated in the following indications:

•Ulcerative colitis ("UC"): Phase 3 clinical trials for the treatment of adults with moderately to severely

active UC are ongoing ("ABTECT"). On July 22, 2025, we announced the positive Phase 3 results of our

ABTECT 8-week induction trials. On June 1, 2026, we announced positive results from Part 1 of the Phase 3

ABTECT 44-week maintenance trial, demonstrating strong efficacy, including robust endoscopic remission,

and on June 29, 2026, we announced positive topline results from Part 2 of the maintenance trial. Part 2 of the

maintenance trial enrolled patients who either did not achieve clinical response following induction treatment

or who experienced disease relapse during the re-randomized maintenance trial (Part 1), expanding both the

efficacy and safety results in a more refractory patient population than the registrational maintenance cohort.

Following a positive pre-NDA ("New Drug Application") interaction with the U.S. Food and Drug

Administration ("FDA"), we aligned with the agency on the planned content, format and submission strategy

for obefazimod’s NDA for adults with moderately to severely active UC. We believe we remain on track to

submit our NDA to the U.S. FDA in the fourth quarter of 2026.

•Crohn’s disease ("CD"): Our ENHANCE-CD Phase 2b clinical trial of obefazimod in patients with CD is

still ongoing, and the 12-week induction topline data read-out is expected inmid-2027.

•Combination therapy: In September 2024, we announced initial preclinical combination data of obefazimod

combined with etrasimod in a mouse model ofinflammatory bowel diseases ("IBD"). The results showed that

treatment with the combination improved the response on body weight protection and Disease Activity Index

and a synergistic and statistically significant reduction of several cytokines (TNFa, IL-17, IL-6, IFNg) in the

blood compared to each drug alone. Additional preclinical data to support our decision-making on a

combination agent is expected by the end of 2026.

•Anti-fibrotic effects: In February 2026, we announced the results of two pre-clinical sets of experiments

that were performed to assess the anti-fibrotic effects of obefazimod.

In addition, we have launched a research and development program to generate new potential drug candidates

to strengthen our intellectual property portfolio on the miR-124 platform and to identify additional drug candidates

from our proprietary small molecule library that includes additional miR-124 enhancers. We expect toannounce the

selection of a follow-on compoundin 2026.

Recent Developments

Completion of Public Offering on Nasdaq– July 2026

On July 6, 2026, we announced the completion of an underwritten public offering of 7,360,000 ADSs (the

“2026 Offering”), each representing one ordinary share of the Company, which includes the full exercise of the

underwriters’ option to purchase additional ADSs, at a price of$125.00 per ADS (corresponding to€109.71 per

ordinary share, based on the exchange rate of€1.00 =$1.1394 as published by the European Central Bank on June

30, 2026). The net proceeds, after deducting underwriting commissions and estimated offering expenses, were

approximately $874.1 million, equivalent to approximately€767.1 million.

We believe that the net proceeds from the 2026 Offering, together with our current cash and cash

equivalents, will allow us to finance our operations for at least 12 months from the date of issuance of theunaudited

interim condensed consolidated financial statements included inthis half-year report.

Royalty Certificate Repurchase

On May 4, 2026, we entered into a purchase agreement with the holders of our royalty certificates (the

“Holders”) pursuant to which we repurchased all of our royalty certificates for an aggregate price of $90 million

(approximately €76.5 million), of which $45 million was paid in cash on May 7, 2026.

We were granted an interest-free vendor’s loan ("crédit vendeur") in a total amount equal to the remaining $45

million, which was reinvested in our securities by way of set-off against the subscription price of 403,347 ordinary

shares represented by ADSs issued to the Holders, at an offering price of $111.57 per ADS (corresponding to €95.34

per ordinary share). The set-off and the corresponding issuance and delivery of the ADSs to the Holders occurred on

May 7, 2026. The vendor’s loan was fully extinguished at that date. All of the royalty certificates were immediately

cancelled following the transaction.

The repurchase of our royalty certificates on May 7, 2026 resulted in the recognition of an expense of

approximately €43.2 million in the second quarter of 2026. The amount corresponds to the difference between the

royalty certificates' carrying amount on the repurchase date of €33.5 million and the total consideration transferred,

comprising cash and equity consideration of €38.2 million and €38.5 million, respectively, based on the exchange

rates prevailing at the capital increase date and the settlement dates (including the €0.2 million effect of a net foreign

exchange loss on the cash settlement). Consequently, the €5.8 million deferred tax liability recognized in our

statements of financial position as of December 31, 2025 has been derecognized, and a corresponding tax income

has been recognized, for the six-month period ended June 30, 2026.

Three-Year Interim Data from Our Phase 2a/2b Open-Label Extension Trial (Study 108) of Obefazimod

On May 22, 2026, we reported three-year interim data from Study 108, a Phase 2a/2b open-label maintenance

("OLM") trial of obefazimod following dose de-escalation in patients with ulcerative colitis. In this study, patients

who had completed the four-year Phase 2a or two-year Phase 2b OLM trials, where they had received 50 mg of

once-daily obefazimod, were given the opportunity to continue receiving obefazimod at a reduced dose of 25 mg

daily for up to five additional years (provided they met the eligibility criteria of Mayo Endoscopic Subscore = 0 or

1). A total of 130 patients entered the trial, and as of the January 5, 2026 cutoff date, 80% (104/130) were still

enrolled and completed the full 144-week evaluation.

At study baseline, 89% (116/130) of patients were in clinical remission. At weeks 48, 96 and 144 of treatment,

73% (95/130), 69% (90/130), and 68% (88/130) of patients evaluated were in clinical remission, respectively.

Clinical remission, inclusive of endoscopic subscore, was evaluated in the intent-to-treat population using non-

responder imputation. Similar trends were observed with other efficacy analyses, and no new safety signals were

observed. We believe these data demonstrated durable clinical remission and a favorable long-term safety profile

with up to seven years of obefazimod exposure, reinforcing the durability and safety data observed across the Phase

3 ABTECT program.

Results of Operations

The following discussion covers the material changes in financial condition and results of operations for the three

and six-months ended June 30, 2025 and June 30, 2026, for which consolidated statements of loss are presented in

the accompanying financial statements.

Comparison of the Three Months Ended June 30 2025 and 2026

The following table sets forth our results of operations for thethree months ended June 30 2026 and 2025.

Total Operating Income

For thethree months ended June 30 2026 our total operating income was€1.2 million, as compared to€1.1

million for thethree months ended June 30 2025, an increaseof€0.1 million or 10% as detailed below.

Other Operating Income

Thefollowing table sets forth our other operating income for thethree months ended June 30 2026 and 2025.

For thethree months ended June 30 2026, our other operating income was€1.2 million, as comparedto€1.1

million for thethree months ended June 30 2025, an increase of€0.1 million, or 10%, as detailed below.

Research Tax Credits ("CIR")

For thethree months ended June 30 2026, we recognized research tax credits for our research and

development projects of€1.0 million, as compared to€1.0 million for thethree months ended June 30 2025, a

decrease of€(0.1) million, or(7)%. The comparatively limited decrease in research tax credits, despite a€19.7

million, or 51%, increase in research and development expenses for thethree months ended June 30 2026 as

compared to thethree months ended June 30 2025, was primarily attributable to the statutory cap applicable to

eligible outsourced research and development expenses.

Depositary Service Fees

As part of our depositary agreement with Citibank (which is acting as our exclusive depositary for our

publicly listed ADSs), we are entitled to receive a portion of the fees collected by Citibank on ADS transactions

(e.g., issuance, cancellation and depositary service fees).

For thethree months ended June 30 2026, our income related to depositary service fees was €0.2 million, as

compared to€0.05 million for thethree months ended June 30 2025, an increase of€0.2 million, or 391%. The 2026

fees mainly reflect the larger number of transactions that occurred during the second quarter of 2026 compared to

Total Operating Expenses

For thethree months ended June 30 2026, our total operating expenses were€85.3 million, as compared to

€47.6 million for thethree months ended June 30 2025, an increase of€37.7 million, or 79%. This increase was

primarily due to an increase in research and development expenses of€19.7 million, an increase in general and

administrative expenses of€15.8 million and an increase in sales and marketing expenses of€2.2 million, each as

described below.

Sales and Marketing Expenses

Salesand marketing expenses consist primarily of personnel expenses, including share-based compensation

expenses, for employees engaged in sales and marketing activities, as well as consulting costs associated with

market research in preparation for our potential future sales and commercialization efforts in the U.S.

For thethree months ended June 30 2026, our total sales and marketing expenses were€2.9 million, as

compared to€0.7 million for the three months ended June 30 2025, an increase of€2.2 million, or 328%. The

increase was predominantly driven by costs related to our preparation for potential future sales and

commercialization efforts for obefazimod in the U.S. (including the hiring of our commercial leadership team).

Research and Development Expenses

Thefollowing table sets forth our research and development expenses by drug candidate and therapeutic

indication for thethree months ended June 30 2026 and 2025.

For thethree months ended June 30 2026, our research and development expenses were€58.3 million, as

comparedto €38.6 million for thethree months ended June 30 2025, an increase of€19.7 million, or 51%.

This increase was primarily due to (i) an increase in expenses related to our UC program of€12.4 million, or

55%, attributable to an increasein share-based compensation expense related to the impact of share-based

compensation awards granted in 2025 and partly offset bydecreased activity on our ABTECT clinical program as a

result of reaching a major milestone with our Phase 3 induction trials in 2025. The increase was secondarily due to

(ii)anincrease in expenses related to our CD program of€4.3 million, or 106%, resulting from the progression of

our Phase 2b trials in CD, (iii) an increase in expenses related to transversal activities of€2.6 million, or 30%,

mainly due to increased chemistry, manufacturing and controls ("CMC") and supply chain costs related to the

progression of clinical trials and anticipation of potential future commercial launch and (iv)an increasein expenses

related to new indications (including combination therapy)for obefazimod of€0.6 million or 49%.

In aggregate, the increasein share-based compensation expense related to the impact of share-based

compensation awards granted in 2025 contributedto the overall increase in research and development expenses in an

amount of €6.2 million (of which €4.3 million related to UC, and €1.9 million related to CD). The related employer

tax and social contributions further contributed to the overall increase across all destinations in an amount of €6.7

million.

General and Administrative Expenses

For thethree months ended June 30 2026, our general and administrative expenses were€24.1 million, as

compared to€8.3 million for thethree months ended June 30 2025, an increase of€15.8 million, or 191%. This

increase was primarily due to a€12.0 million, or 218%, increase in personnel costs, primarily attributable to an

increasein share-based compensation expense related to the impact of share-based compensation awards granted in

2025 and the related tax and social contributions, in an amount of €9.8 million, and to a lesser extent to the increase

in our headcount. The increase was also due toa€3.1 million, or 173%, increasein consulting andprofessional fees,

driven by increased costs associated with building our infrastructure to support future growth in our operationsand

to a lesser degree by a€0.8 million, or 78%, increase in other general and administrative expenses.

Operating Loss

For thethree months ended June 30 2026, our net operating loss was€84.1 million, as compared to a net

operating loss of€46.5 million for thethree months ended June 30 2025, an increase of€37.6 million, or 81%. This

was primarily due to a€19.7 million, or 51%, increasein research and development expenses, an increase of€15.8

million, or 191%, in general and administrative expenses and an increase in sales and marketing expenses of€2.2

million, or 328%.

Financial Loss

For thethree months ended June 30 2026, our net financial loss was€39.4 million, as compared to a net

financial loss of€1.9 million for thethree months ended June 30 2025, mainly driven by the€43.2 million loss on

derecognition of our royalty certificates following their repurchase on May 7, 2026, partly offset by (i) interest

income of €1.2 million and fair value changes of €2.1 million inrelation to the invested proceeds from our U.S.

initial public offering and listing on Nasdaq and (ii) foreign exchange gains of €1.3 million.

Forthe three months ended June 30 2025, our net financial loss of€5.4 million was mainly driven by (i)

interest expenses of €3.4 million related to the first tranche of senior secured convertible bonds with warrants

attached in the Kreos / Claret Financing (the "Kreos / Claret OCABSA"), the second and third tranches of the senior

secured bonds in the Kreos / Claret Financing (drawn on March 28, 2024 and June 21, 2024 respectively) and the

senior convertible notes in the Heights Financing (the "Heights Convertible Notes"), (ii) non-cash expenses of €0.5

million related to the increase in the fair value of our derivatives and (iii) foreign exchange losses of €1.4 million

(including the €1.1 million non-cash impact of the revaluation of U.S. dollar-denominated cash and cash equivalents

as of June 30, 2025).

These costs were partly offset mainly by our financial income of€3.5 million, primarily related to a non-cash

income of €2.8 million related to the decrease in the fair value of the Heights Convertible Notes.

Income Taxes

For thethree months ended June 30 2026, our tax income was €6.1 million, as compared to €— million for the

three months ended June 30, 2025, attributable to the derecognition of our net deferred tax liability of€6.1 million

recognized in our unaudited interim condensed consolidated statements of financial position as of March 31, 2026.

The deferred taxliability resulted from the significant taxable temporary difference arising from our royalty

certificates as of March 31, 2026, which in turn resulted from the difference between (i) the amount already

deductible from our taxable income as of March 31, 2026 (based on the certificates' fair value minus their

subscription price) and (ii) the amount of the related financial liability recognized in our condensed consolidated

statements of financial position at that date (measured at amortized cost using the original effective interest rate).

Further explanationon the calculation of the deferred tax liability is disclosed in Note 22 to our financial

statements as of and for the year ended December 31, 2025 included in our Annual Report on Form 20-Ffor the year

ended December 31, 2025.

The tax income is non-cash for the three months ended June 30, 2026.

Net Loss

For thethree months ended June 30 2026, our net loss was€117.4 million, as compared to€48.4 million for

thethree months ended June 30 2025, an increase of€69.0 million, or 143%, mainly driven by an increase in

financial loss of€37.5 million and an increase in operating loss of€37.6 million, as described above.

Comparison of the Six Months Ended June 30 2025 and 2026

The following table sets forth our results of operations for thesix months ended June 30, 2025 and 2026.

Total Operating Income

For thesix months ended June 30, 2026, our total operating incomewas€2.5 million, as compared to€2.1

million for thesix months ended June 30, 2025, an increase of€0.5 million, or 22%, as detailed below.

Other Operating Income

Thefollowing table sets forth our other operating income for thesix months ended June 30, 2025 and 2026.

For thesix months ended June 30, 2026, our other operating income was €2.5 million, as compared to€2.1

million for thesix months ended June 30, 2025, an increase of€0.5 million, or 22%, as detailed below.

Research Tax Credits ("CIR")

For thesix months ended June 30, 2026, we recognized research tax credits for our research and development

projects of€2.1 million, as compared to€2.0 million for thesix months ended June 30, 2025, an increase of€0.1

million, or 5%. The comparatively limited increase in research tax credits, despite a€(29.9) million, or 38%,

increase in research and development expenses for thesix months ended June 30, 2026 as compared to thesix

months ended June 30, 2025, was primarily attributable to the statutory cap applicable to eligible outsourced

research and development expenses.

Depositary Service Fees

As part of our depositary agreement with Citibank (which is acting as our exclusive depositary for our

publicly listed ADSs), we are entitled to receive a portion of the fees collected by Citibank on ADS transactions

(e.g., issuance, cancellation and depositary service fees).

For thesix months ended June 30, 2026, our income related to depositary service fees was€0.4 million, as

compared to€0.1 million for thesix months ended June 30, 2025, an increase of€0.4 million, or 512%. The increase

mainly reflects the larger number of transactions that occurred during the first half of 2026 compared to the first half

of 2025.

Total Operating Expenses

For thesix months ended June 30, 2026, our total operating expenses were€142.9 million, as compared to

€95.8 million for thesix months ended June 30, 2025, an increase of€47.1 million, or 49%. This increase was

primarily due to an increase in research and development expenses of€29.9 million, an increase in general and

administrative expenses of€14.1 million and an increase in sales and marketing expenses of€3.1 million, each as

described below.

Sales and Marketing Expenses

Salesand marketing expenses consist primarily of personnel expenses, including share-based compensation

expenses, for employees engaged in sales and marketing activities, as well as consulting costs associated with

market research in preparation for our potential future sales and commercialization efforts in the U.S.

For thesix months ended June 30, 2026, our total sales and marketing expenses were€4.6 million, as

compared to€1.5 million for the six months ended June 30, 2025, an increase of€3.1 million, or 202%. The increase

was predominantly driven by costs (including personnel costs) related to our preparation for potential future sales

and commercialization efforts for obefazimod in the U.S.

Research and Development Expenses

Thefollowing table sets forth our research and development expenses by drug candidate and therapeutic

indication for thesix months ended June 30, 2025 and 2026.

For thesix months ended June 30, 2026, our research and development expenses were€107.9 million, as

comparedto €77.9 million for thesix months ended June 30, 2025, an increaseof€29.9 million, or 38%.

This increase was primarily due to an increase in expenses related to our UC program of€8.5 million, or 16%,

attribut able to an increasein share-based compensation expense related to the impact of share-based compensation

awards granted in 2025 and partly offset by decreased activity in our ABTECT clinical program as a result of

reaching a major milestone with our Phase 3 induction trials in 2025, an increasein expenses related to new

indications (including combination therapy)for obefazimod of€6.8 million or 227%, an increase in expenses related

to our CD program of€6.3 million, or 85%, resulting from the progression of our Phase 2b trials in CD and an

increase in expenses related to transversal activities of€4.6 million, or 31%, mainly due to increased CMC and

supply chain costs related to the progression of clinical trials and anticipation of potential future commercial launch.

In aggregate, an the increasein share-based compensation expense related to the accelerated vesting of certain

of our former Chief Scientific Officer's AGAs in March 2026, as well as the impact of share-based compensation

awards granted in 2025, contributedto the overall increase in research and development expenses in an amount of

€23.7 million (of which €10.8 million related to UC, €6.1 million related to Obefazimod Other Indications and €3.9

million related to CD). The related employer tax and social contributions further contributed to the overall increase

across all destinations in an amount of €8.4 million.

General and Administrative Expenses

For thesix months ended June 30, 2026, our general and administrative expenses were€30.4 million, as

comparedto€16.3 million for thesix months ended June 30, 2025, an increase of€14.1 million, or 86%. This

increase was primarily due to a€8.6 million, or 81%, increase in personnel costs, primarily attribut able to an

increasein share-based compensation expense related to the impact of share-based compensation awards granted in

2025 and the related tax and social contributions, in an amount of €6.1 million, and to a lesser extent to the increase

in our headcount. The increase was also due toa€4.5 million, or 121%, increasein consulting and professional fees,

driven by increased costs associated with building our infrastructure to support future growth in our operationsand

to a lesser degree by a€1.0 million, or 51%, increase in other general and administrative expenses.

Operating Loss

For thesix months ended June 30, 2026, our net operating loss was€140.3 million, as compared to a net

operating loss of€93.7 million for thesix months ended June 30, 2025, an increaseof€46.6 million, or 50%. This

increase was primarily due to an increase in research and development expenses of€29.9 million or 38%, an

increase in general and administrative expenses of€14.1 million or 86% andan increase in sales and marketing

expenses of€3.1 million or 202%.

Financial Loss

For thesix months ended June 30, 2026, our net financial loss was €31.4 million, as compared to a net

financial loss of€7.1 million for thesix months ended June 30, 2025, was mainly driven by (i) the€43.2 million loss

on derecognition of our royalty certificates following their repurchase on May 7, 2026,(ii) non-cash expenses of

€3.2 million related to our royalty certificates and (iii) foreign exchange losses of €2.4 million, partly offset by (i)

foreign exchange gains of €10.0 million (including the €6.7 million and €2.7 million non-cash impacts of the

revaluation of U.S. dollar-denominated intercompany receivables and cash and cash equivalents, respectively, as of

June 30, 2026) and (ii) interest income of €1.9 million and fair value changes of €5.4 million inrelation to the

invested proceeds from our U.S. initial public offering and listing on Nasdaq.

Forthe six months ended June 30, 2025, our financial loss of€7.1 million was mainly driven by interest

expenses of €6.9 million in relation to the first tranche of Kreos / Claret OCABSA, the second and third tranches of

the senior secured bonds in the Kreos / Claret Financing (drawn on March 28, 2024 and June 21, 2024 respectively)

and the Heights Convertible Notes, non-cash expense of €1.1 million in relation to our royalty certificates and

foreign exchange losses of €2.3 million (including the €0.4 million non-cash impact of the revaluation of U.S.

dollar-denominated cash and cash equivalents as of June 30, 2025).

These costs were partly offset mainly by interest income of €1.1 million in relation to the invested proceeds

from our U.S. initial public offering and listing on Nasdaq, a non-cash income of €1.3 million related to the decrease

in the fair value of the Heights Convertible Notes and a €0.5 million income related to the fair value changes of

certain of our cash equivalents.

Income Taxes

For the six months ended June 30, 2026, our tax income was€5.8 million, as compared to€— million for the

six months ended June 30, 2025, attributable to thederecognition ofour net deferred tax liability of€5.8 million

recognized in our consolidated statements of financial position as of December 31, 2025.

The deferred taxliability resulted from the significant taxable temporary difference arising from our royalty

certificates as of December 31, 2025, which in turn resulted from the difference between (i) the amount already

deductible from our taxable income as of December 31, 2025 (based on the certificates' fair value minus their

subscription price) and (ii) the amount of the related financial liability recognized in our condensed consolidated

statements of financial position at that date (measured at amortized cost using the original effective interest rate).

Further explanationon the calculation of the deferred tax liability is disclosed in Note 22 to our financial

statements as of and for the year ended December 31, 2025 included in our Annual Report on Form 20-F for the year

ended December 31, 2025.

The deferred tax expense is non-cash for the six months ended June 30, 2026.

Net Loss

For thesix months ended June 30, 2026, our net loss was€165.9 million, as compared to€100.8 million for

thesix months ended June 30, 2025, an increase of€65.1 million, or 65%, mainly driven by an increase in financial

loss of€24.3 million and an increase inoperating loss of€46.6 million, as described above.

Liquidity and Capital Resources

Sources of Liquidity

We have incurred substantial operating losses since inception and expect to continue to incur significant

operating lossesfor the foreseeable future and may never become profitable. For thesix months ended June 30, 2025

and 2026, we reported net losses of€100.8 million and€165.9 million, respectively. As of December 31, 2025, we

carried forward accumulated tax losses of€912.9 million.

Since inception, we have financed our operations through the issuance of ordinary shares with gross aggregate

proceeds of€2,002.1 million, of which€130.0 million of gross proceeds were from offerings of our ordinary shares

on Euronext Paris in February 2023,€223.3 million of gross proceeds were from offering of our ordinary shares in

the form of ADS on the Nasdaq Global Market in our U.S. initial public offering as well as ordinary shares in

Europe (including France) and countries outside of the United States in a private placement in October 2023,€637.5

million of gross proceeds were from the offering of our ordinary shares in the form of ADS on the Nasdaq Global

Market in July 2025 (the "2025 Offering"),€807.4 million of gross proceeds were from the offering of ordinary

shares in the form of ADSs on the Nasdaq Global Market in July 2026 (the “2026 Offering”), bank borrowings and

structured loans of €175.0 million, reimbursements of CIR in an amount of€41.2 million, grants received from

Bpifrance (including €21.3 million of subsidies and €1.8 million of conditional advances) and royalty certificates in

an amount of €2.9 million.

In addition, on November 19, 2024, we entered into an equity distribution agreement with Piper Sandler & Co.

("Piper Sandler") allowing us to issue and sell from time to time, in one or more "at the market" offerings through

Piper Sandler acting as sales agent, ordinary shares in the form of ADSs, each ADS representing one ordinary share,

nominal valueof €0.01 per share, with aggregate gross sales proceeds of up to $150.0 million (the "ATM Program").

To date, we have not sold any ADSs pursuant to the ATM Program.

Based on (a) our existing cash and cash equivalents and other short-term investments of€402.4 million as of

June 30, 2026 and (b) the net proceeds from the July 2026 Offering of€767.1 million, we expect, as of the date of

issuance of theunaudited interim condensed consolidated financial statements included inthis half-year report, to be

able to fund our forecasted cash flow requirements as they fall due for at least 12 months. Our forecasted cash flow

requirements reflect continued investment in the extension of the Phase 3 clinical program for obefazimod in UC,

the advancement of the Phase 2b ENHANCE-CD clinical trial in CD, with expected 12-week induction topline

results in mid-2027, the planned submission of an NDA for obefazimod in UC in the fourth quarter of 2026, and the

continued buildout of the U.S. commercial organization in preparation for a potential commercial launch of

obefazimod in UC, if approved. Our forecasted cash flow requirements also include ongoing general and

administrative expenses, working capital requirements and other operating activities necessary to support our

business.

Based on the above, management has concluded that our existing cash, cash equivalents and other short-term

investments aresufficient to fund our operating and capital expenditure requirements for a period greater than 12

months from the date of issuance of the financial statements accompanying this half-year report, and the

accompanying financial statements have been prepared on a going concern basis.

Capital Increases

On July 28, 2025, we received gross proceeds of €637.5 million from the issuance of 11,679,400 ordinary

shares in the form of ADSs, at a price of $64.00 per share (corresponding to €54.58 per ordinary share).

On May 7, 2026, as part of the settlement of the repurchase of our royalty certificates, we issued 403,347

ordinary shares in the form of ADSs to the benefit of the holders of our royalty certificates, at an offering price of

$111.57 per share (corresponding to€95.34 per ordinary share), representing an aggregate amount of €38.5 million.

On July 6, 2026, we received gross proceeds of€807.4 million from the issuance of 7,360,000 ordinary shares

in the form of ADSs, at a price of $125.00 per share (corresponding to €109.71 per ordinary share).

Research Tax Credits

Fromour inceptionto June 30, 2026, we have benefited from refunds of CIRs in a total amount of€41.2

million.

We currently expect to receive CIRs of€3.2 million with respect to eligible research expenses incurred during

the year ended December 31, 2025 in the second half of 2026.

In June 2025, we received CIRs of€5.7 million with respect to eligible research expenses incurred during the

year ended December 31, 2024.

Indebtedness

For a description of material financing agreements, see "Item 10.C. Material Contracts" of the Company’s

Annual Report on Form 20-F for the year ended December 31, 2025.

In connection with the repurchase of our royalty certificates in May 2026, we were granted an interest-free

vendor’s loan ("crédit vendeur") in a total amount equal to $45 million, which was reinvested in our securities by

way of setoff against the subscription price of 403,347 ordinary shares in the form of ADSs issued to the benefit of

the royalty certificate holders, at an offering price of $111.57 per ADS (corresponding to€95.34 per ordinary share).

The set-off and the corresponding issuance and delivery of the ADSs to the holders occurred on May 7, 2026. The

vendor's loan was fully extinguished at that date. The royalty certificates were immediately cancelled following the

transaction.

Historical Changes in Cash Flows

Thefollowing table sets forth our cash inflows and outflows for the six-month periods ended June 30, 2025

and 2026.

Operating Activities

For thesix months ended June 30, 2026, cash used in operating activities was€102.5 million, as compared to

€66.6 million for thesix months ended June 30, 2025, an increase of€35.9 million, or 54%. Net cash used in

operating activities for both periods was predominantly related to payments for the progression of our UC and CD

trials and personnel, legal, professional and infrastructure costs associated with operating as a dual-listed public

company. The increase was mostly driven by the increase in our operating loss (as explained above), partly offset by

changes in our working capital requirements of €15.5 million for the six months ended June 30, 2025, resulting

primarily from an increase in our trade payables reflecting the progress of our Phase 3 clinical trials. For the six

months ended June 30, 2026, the changes in our working capital requirements further contributed to our net cash

used in operating activities for €3.7 million.

Investing Activities

For thesix months ended June 30, 2026, cash provided by investing activities amounted to€1.5 million,

primarily reflecting interest received on our invested proceeds from our 2025 Offering.

For the six months ended June 30, 2025, cash provided by investing activities amounted to€1.1 million and

wasmainly driven by €1.0 million of interest received on our invested proceeds from our initial public offering on

the Nasdaq Global Market and private placement in October 2023.

Financing Activities

For thesix months ended June 30, 2026, cash used in financing activities was€39.3 million, which primarily

consisted of the portion of the repurchase of our royalty certificates settled in cash (€38.2 million).

For thesix months ended June 30, 2025, cash used in financing activities was€16.6 million, which consisted

of repayments of €12.6 million (of which €9.1 million under the tranches A, B and C of the Kreos / Claret

Financing, €2.2 million under the Heights Convertible Notes and €1.2 million under the PGE) and interest payments

of€3.9 million.

Material Cash Requirements

Contractual Obligations and Loans

Thefollowing table sets forth information about material contractual obligations as of June 30, 2026.

Thecommitment amounts in the table below are associated with contracts that are enforceable and legally

binding and that specify all significant terms, including fixed or minimum services to be used, fixed, minimum or

variable price provisions, and the approximate timing of the actions under the contracts. Future events could cause

actual payments to differ from these estimates. All amounts except the retirement benefits in the table below are

presented gross and are undiscounted.

In the ordinary course of our business, we regularly use the services of subcontractors and enter into research

and partnership arrangements with various contract research organizations (“CROs”) and with public-sector partners

orsubcontractors, who conduct clinical trials and studies in relation to our drug candidates. Off-balance sheet

obligations in the table above are commitments related to these research and partnership agreements. They are

classified at less than one year maturity in the absence of a fixed schedule in contracts, in case of multiple-year

contracts, such as CRO contracts. CRO contracts include payments that are conditional to the completion of future

development milestones. The majority of the commitments with our CROs are cancellable under certain

circumstances such as insolvency, study put on hold by competent authorities, breach in regulations or negligence in

the provision of the services.

As of June 30, 2026, our contractual obligations were€188.3 million, comprising off-balance sheet obligations

of€186.3 million with respect to purchase obligations, lease obligations of€1.2 million and retirement benefits

obligations of€0.7 million.

INDEX TO UNAUDITED INTERIM CONDENSED CONSOLIDATED FINANCIAL STATEMENTS