6-K

Abivax S.A. (ABVX)

6-K 2025-12-15 For: 2025-09-30
View Original
Added on April 04, 2026

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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 December 2025

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 ☐

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On December 15, 2025, Abivax SA (the "Registrant") announced its financial results as of and for the three and nine

months ended September 30, 2025 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 No. 333-286069) 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to the extent not superseded by documents or reports subsequently filed.

Exhibit Index
Exhibit 99.1 Press release, dated December 15, 2025
Exhibit 99.2 Unaudited Interim Condensed Consolidated Financial Statements

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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.

Abivax SA<br><br>(Registrant)
Date: December 15, 2025 /s/ Marc de Garidel
Chief Executive Officer

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Exhibit 99.2

Unaudited Interim Condensed Consolidated Financial Statements

TABLE OF CONTENTS

Page
INTRODUCTION................................................................................................................. 1
RISK FACTORS................................................................................................................... 3
OPERATING RESULTS........................................................................................................ 4 INDEX TO THE UNAUDITED INTERIM CONDENSED CONSOLIDATED FINANCIAL<br><br>STATEMENTS......................................................... F-1
--- ---

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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 quarterly

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

referred to in this quarterly 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 quarterly 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 quarterly report includes our unaudited interim condensed consolidated financial statements of financial

position as of September 30, 2025 and December 31, 2024 and the related unaudited condensed consolidated

statements of loss and comprehensive loss for each of the three- and nine-month periods ended September 30, 2025

and September 30, 2024 and the unaudited condensed consolidated statements of cash flows and changes in

shareholder's equity for the nine-month periods ended September 30, 2025 and September 30, 2024, 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 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 quarterly 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 quarterlyr 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 quarterly 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 quarterly report, including

statements regarding our future results of operations and financial positions, business strategy, plans and our

objectives for future operations, are forward-looking statements. When used in this quarterly 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 drug candidates;

•the potential attributes and clinical advantages of our 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;

•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 for any of our 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 propriety

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

technology of third parties;

•our expectations regarding our cash requirements;

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•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 Israel-Hamas war), 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, 2024 filed with the Securities and Exchange Commission (“SEC”) on March 24,

2025 (the “Annual Report”) under the caption “Item 3.D—Risk Factors” for a more complete understanding of the

risks and uncertainties material 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.

This quarterly report contains market data and industry forecasts that were obtained from industry publications.

These data involve a number of assumptions and limitations, and you are cautioned not to give undue weight to such

estimates. We have not independently verified any third-party information. While we believe the market position,

market opportunity and market size information included in this quarterly report is generally reliable, such

information is inherently imprecise.

Rounding of Figures

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

in this quarterly 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.

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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, 2024. 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.

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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. Top-line results from the 44-week maintenance data read-out are

expected during the second quarter of 2026.

•Crohn’s disease (“CD”): On October 3, 2024, we announced the first patient was enrolled in our

ENHANCE-CD Phase 2b clinical trial of obefazimod in patients with CD, and the 12-week induction data

read-out is expected in second half of 2026.

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

combined with etrasimod in a mouse model of inflammatory 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 in 2025.

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 to announce a

follow-on candidate selection in a new indication in the second half of 2025.

Results of Operations

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

months ended September 30, 2024 and September 30, 2025, as well as the three months ended September 30, 24 and

September 30, 2025, for which consolidated statements of loss are presented in the accompanying financial

statements.

Comparison of the Three-Month Ended September 30, 2024 and 2025

The following table sets forth our results of operations for the three month ended September 30, 2024 and

2025.

(In thousands of euros) Three Months Ended<br><br>September 30, 2024 Three Months Ended<br><br>September 30, 2025 % Change
Other operating income ................................ 1,324 2,043 54%
Total operating income ........................................ 1,324 2,043 54%
Sales and marketing expenses ............................ (853) (1,838) 115%
Research and development expenses ............ (43,286) (55,416) 28%
General and administrative expenses ........... (7,375) (25,500) 246%
Total Operating expenses .................................... (51,514) (82,755) 61%
Operating income (loss) ............................................ (50,189) (80,712) 61%
Financial expenses ........................................ (8,474) (93,051) 998%
Financial income .......................................... 3,436 20,404 494%
Financial loss ......................................................... (5,037) (72,647) 1,342%
Net loss before tax ................................................ (55,227) (153,358) 178%
Income Tax .................................................... —%
Net loss for the period .......................................... (55,227) (153,358) 178%

Total Operating Income

For the three months ended September 30, 2025, our total operating income was €2.0 million, as compared

to €1.3 million for the three months ended September 30, 2024, an increase of 54% as detailed below.

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Other Operating Income

The following table sets forth our other operating income for the three month ended September 30, 2024

and 2025.

(In thousands of euros) Three Months Ended<br><br>September 30, 2024 Three Months Ended<br><br>September 30, 2025 % Change
CIR (Research Tax Credits) ................................... 1,332 639 (52)%
Subsidies : ............................................................. 20 (100)%
Other ...................................................................... (27) 1,404 (5,239)%
Total other operating income ............................. 1,324 2,043 54%

For the three months ended September 30, 2025, our total operating income was €2.0 million, as compared to

€1.3 million for the three months ended September 30, 2024. The increase of €0.7 million or 54% was mainly due to

the recognition issuance, cancellation and depositary service fees collected from our ADSs holders and presented

within the line item "Other" in 2025, partly offset by a decrease in research tax credits.

Research Tax Credits

For the three months ended September 30, 2025, we recognized research tax credits for our research and

development projects of €0.6 million, as compared to €1.3 million for the three months ended September 30, 2024.

Although research and development expenses for the three months ended September 30, 2025 increased by 28% as

compared to the three months ended September 30, 2024, the €(0.7) million decrease is mainly driven by (i) the

maximum amount of eligible outsourced research and development expenses being capped, (ii) a decrease in internal

research and development costs (for €0.4 million), (iii) the reimbursement of the CARENA and RNP-VIR

conditional advances, deducted from the 2024 CIR calculation (for €0.1 million) and (iv) a change in the CIR

regulation related to eligible expenses (for €0.2 million).

Other

As part of our agreement with Citibank (who is acting as our exclusive depositary for our publicly listed

and freely traded ADSs), we are entitled to receive part of the fees collected by Citibank on ADSs transactions. For

the three months ended September 30, 2025, we recognized income related related to issuance, cancellation and

depositary service fees of €1.4 million, as compared to €0 thousand for the three months ended September 30, 2024.

The increase reflects the large number of transactions that occurred over the third quarter of 2025, following the

announcement of our Phase 3 results and the completion of our Nasdaq Offering in July 2025.

Total Operating Expenses

For the three months ended September 30, 2025, our total operating expenses were €82.8 million, as

compared to €51.5 million for the three months ended September 30, 2024, an increase of €31.2 million, or 61%.

This increase was primarily due to an increase in research and development expenses of €12.1 million, an increase in

general and administrative expenses of €18.1 million and to a lesser degree, an increase in sales and marketing

expenses of €1.0 million, each as described below.

Sales and Marketing Expenses

For the three months ended September 30, 2025, our total sales and marketing expenses were €1.8 million,

as compared to €0.9 million for the three months ended September 30, 2024, an increase of €1.0 million, or 115%.

The increase was predominantly driven by an increase in our stock-based compensation expense ("AGAs"),

including a €0.4 million increase in employer tax and social contributions, in turn explained by the uptick in our

share price during the third quarter of 2025.

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Research and Development Expenses

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

indication for the three month ended September 30, 2024 and 2025.

(In thousands of euros) Three Months Ended<br><br>September 30, 2024 Three Months Ended<br><br>September 30, 2025 %  Change
OBEFAZIMOD ................................................... 43,277 53,758 24%
Ulcerative Colitis ............................................... 32,453 40,856 26%
Crohn's Disease ................................................. 5,170 4,057 (22)%
Obefazimod Others Indications ........................ 343 3,308 865%
Transversal activities ......................................... 5,311 5,538 4%
Others .................................................................... 9 1,659 18,127%
Research and Development expenses ................. 43,286 55,416 28%

For the three months ended September 30, 2025, our research and development expenses were

€55.4

million, as compared to €43.3 million for the three months ended September 30, 2024, an increase of €12.1 million,

or 28%. This increase was primarily due to the continued progression of our UC clinical program and Phase 3

induction read out during the third quarter of 2025 of €8.4 million, or 26% and an increase in costs related to new

indications (including the combination therapy) for obefazimod by €3.0 million, or 865%. These increases were

partially offset by a decrease in expenses related to our CD program of €1.1 million, or (22)%, due to €1.7 million in

milestone costs for first site initiation in our phase 2b trial that occurred in Q3 of 2024.

In addition, a sharp rise in employer tax and social contributions related to our stock-based compensation

("AGAs"), in turn explained by the uptick in our share price during the third quarter of 2025, contributed to the

overall increase across all destinations, in an amount €14.5 million for the three-months ended September 30, 2025

compared to September 30, 2024).

General and Administrative Expenses

(In thousands of euros) Three Months Ended<br><br>September 30, 2024 Three Months Ended<br><br>September 30, 2025 %  Change
Personnel costs ....................................................... 4,051 21,042 419%
Consulting and professional fees ............................ 2,229 3,542 59%
Other general and administrative expenses ............ 1,095 917 (16)%
General and administrative expenses ................. 7,375 25,500 246%

For the three months ended September 30, 2025, our general and administrative expenses were

€25.5 million, as compared to €7.4 million for the three months ended September 30, 2024, an increase of

€18.1 million, or 246%. This increase was primarily due to a €17.0 million, or 419%, increase in personnel costs

mainly explained by the increase in employer tax and social contributions related to our AGAs by €14.8 million

resulting from the uptick in our share price during the third quarter of 2025, and to a lesser degree by an increase in

consulting and professional fees by €1.3 million or 59%, driven by an increase in legal and professional fees and

costs associated with operating as a dual-listed public company.

Operating Loss

For the three months ended September 30, 2025, our net operating loss was €80.7 million, as compared to a

net operating loss of €50.2 million for the three months ended September 30, 2024, an increase of €30.5 million, or

61%. This increase was primarily due to an increase of €12.1 million in research and development expenses and

secondarily due to an increase of €18.1 million in general and administrative expenses, and partially by an increase

of €1.0 million in sales and marketing expenses.

The overall increase is primarily driven by employer tax and social contributions related to our AGAs, due

to the uptick in our share price during the third quarter of 2025, amounting to €29.6 million.

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Financial Income (Loss)

For the three months ended September 30, 2025, our financial loss was €72.6 million, as compared to a

financial loss of €5.0 million, for the three months ended September 30, 2024.

For the three months ended September 30, 2025, our financial loss was €72.6 million and was mainly

driven by (i) increases in the fair values of the senior convertible notes in the Heights Financing (the "Heights

Convertible Notes") and the Kreos / Claret BSA by respectively €29.5 million and €37.4 million (predominantly

driven by the increase in our share price and the remeasurement of these instruments prior to their conversion into

ordinary shares), (ii) foreign exchange losses of €9.1 million (predominantly related to the non-cash impact of the

revaluation of U.S. dollar-denominated cash and cash equivalents as of September 30, 2025), (iii) interest expenses

of €2.5 million in relation 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 and the Heights Convertible Notes, and (iv) a non-cash expense of €14.5 million in

relation to our royalty certificates.

These costs were partially offset mainly by (i) foreign exchange gains of €11.5 million (including the €10.7

million gain related to our July 2025 public offering), (ii) a non cash-income of €3.6 million related to the

extinguishment of the Kreos / Claret Minimum Return Indemnifications liability (following the exercises of the

Kreos / Claret BSA and the conversion of the Kreos OCABSA) and (iii) an interest income of €3.4 million in

relation to the invested proceeds from our U.S. initial public offering on Nasdaq, our debt financings as well as our

July 2025 Nasdaq Offering.

For the three months ended September 30, 2024, our financial loss was €5.0 million and was mainly driven

by (i) interest expenses of €3.6 million in relation to the first tranche of the Kreos / Claret OCABSA, the second and

third tranches of senior secured bonds in the Kreos / Claret Financing (drawn on March 28, 2024 and June 21, 2024,

respectively) and the Heights Convertible Notes, (ii) €2.3 million in relation to foreign exchange gains, (iii) a €1.4

million increase in the fair value of derivatives and (iv) €1,1 million in relation to our royalty certificates.

These costs were partially offset mainly by (i) an interest income of €2.0 million in relation to the invested

proceeds from our U.S. initial public offering and listing on Nasdaq and €1.1 million decrease in the fair value of the

Kreos / Claret share warrants.

Income Taxes

For each of the three month ended September 30, 2024 and 2025, we had no income tax charge.

Net Loss

For the three months ended September 30, 2025, our net loss for the period was €153.4 million ,as

compared to €55.2 million, for the three months ended September 30, 2024, an increase of €98.1 million, or 178%

mainly driven by an increase in financial loss of €67.6 million and an increase in operating expenses €31.2 million

as explained above.

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Comparison of the Nine Month Ended September 30, 2024 and 2025

The following table sets forth our results of operations for the nine months ended September 30, 2024 and

2025.

(In thousands of euros) Nine Months<br><br>Ended September<br><br>30, 2024 Nine Months<br><br>Ended September<br><br>30, 2025 % Change
Other operating income ......................................................... 8,139 4,130 (49)%
Total operating income .................................................................. 8,139 4,130 (49)%
Sales and marketing expenses ................................................. (5,082) (3,372) (34)%
Research and development expenses ...................................... (107,936) (133,362) 24%
General and administrative expenses .................................... (25,306) (41,803) 65%
Total operating expenses ............................................................... (138,325) (178,538) 29%
Operating loss ................................................................................. (130,186) (174,407) 34%
Financial expenses ................................................................. (16,627) (102,478) 516%
Financial income .................................................................... 9,949 22,743 129%
Financial loss .................................................................................. (6,679) (79,735) 1,094%
Net loss before tax .......................................................................... (136,864) (254,142) 86%
Income Tax ............................................................................. —%
Net loss for the period .................................................................... (136,864) (254,142) 86%

Total Operating Income

For the nine months ended September 30, 2025, our total operating income was €4.1 million, as compared to

€8.1 million for the nine months ended September 30, 2024, a decrease of

(49)%

as detailed below.

Other Operating Income

The following table sets forth our other operating income for the nine months ended September 30, 2024 and

2025.

(In thousands of euros) Nine Months<br><br>Ended<br><br>September 30,<br><br>2024 Nine Months<br><br>Ended<br><br>September 30,<br><br>2025 % Change
CIR (Research Tax Credits) .............................................................. 3,997 2,656 (34)%
Subsidies ........................................................................................... 4,140 (100)%
Other ................................................................................................. 2 1,474 71,823%
Total other operating income ........................................................ 8,139 4,130 (49)%

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For the nine months ended September 30, 2025, our other operating income was €4.1 million, as compared to

€8.1 million for the nine months ended September 30, 2024. The decrease of €4.0 million, or (49)%, was mainly due

to the recognition of grants and subsidies in 2024 as well as a decrease in our income from research tax credits,

partly offset by issuance, cancellation and depositary service fees collected from our ADS holders and presented

within the line item "Other" in 2025.

Research Tax Credits

For the nine months ended September 30, 2025, we recognized research tax credits for our research and

development projects of €2.7 million, as compared to €4.0 million for the nine months ended September 30, 2024.

Although research and development expenses for the nine months ended September 30, 2025 increased by 24% as

compared to the nine months ended September 30, 2024, the €1.3 million decrease in research tax credits was

mainly driven by (i) the maximum amount of eligible outsourced research and development expenses being capped,

(ii) a decrease in internal research and development costs (for €0.3 million), (iii) the reimbursement of the CARENA

and RNP-VIR conditional advances, deducted from the 2024 CIR calculation (for €0.6 million) and (iv) a change in

the CIR regulation related to eligible expenses (for €0.4 million).

Subsidies

For the nine months ended September 30, 2025, our subsidy income was nil, as compared to €4.1 million for

the nine months ended September 30, 2024. The decrease is related to the RNP-VIR and CARENA conditional

advances granted by Bpifrance between 2013 and 2019. Following the termination of both projects, in June 2024,

Bpifrance agreed to waive 60% of the remaining conditional advances and accrued interests, resulting in a non-cash

subsidy income of €4.1 million during the nine months ended September 30, 2024 (see Bpifrance - Conditional

Advances and Subsidies within the "Liquidity and Capital Resources" section).

Other

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

listed ADSs), we are entitled to receive part of the fees collected by Citibank on ADS transactions. For the nine

months ended September 30, 2025, we recognized income related to issuance, cancellation and depositary service

fees of €1.5 million, as compared to €0 thousand for the nine months ended September 30, 2024. The increase

reflects the large number of transactions that occurred over the third quarter of 2025, following the announcement of

our Phase 3 results and the completion of our offering of ordinary shares in the form of ADSs on the Nasdaq Global

Market in July 2025 (the “July 2025 Nasdaq Offering”).

Total Operating Expenses

For the nine months ended September 30, 2025, our total operating expenses were €178.5 million, as

compared to €138.3 million for the nine months ended September 30, 2024, an increase of €40.2 million, or 29%.

This increase was primarily due to an increase in research and development expenses of €25.4 million, an increase in

general and administrative expenses of €16.5 million and partially offset by a decrease in sales and marketing

expenses of €1.7 million, each as described below.

Sales and Marketing Expenses

For the nine months ended September 30, 2025, our total sales and marketing expenses were €3.4 million,

as compared to €5.1 million for the nine months ended September 30, 2024, a decrease of €1.7 million, or (34)%.

The decrease was predominantly driven by a reduction in the headcount of our Sales and Marketing department as

well as one-time costs of €1.8 million that were incurred in 2024 for the Group's corporate re-branding, including its

new website.

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Research and Development Expenses

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

indication for the nine months ended September 30, 2024 and 2025.

(In thousands of euros) Nine Months<br><br>Ended<br><br>September 30,<br><br>2024 Nine Months<br><br>Ended<br><br>September 30,<br><br>2025 % Change
Obefazimod ............................................................................................ 105,021 130,919 25%
Ulcerative Colitis ........................................................................... 84,206 92,784 10%
Crohn’s Disease ............................................................................. 6,087 11,472 88%
Obefazimod Other Indications ....................................................... 310 6,295 1,930%
Transversal Activities .................................................................... 14,419 20,367 41%
Others ..................................................................................................... 2,915 2,443 (16)%
Research and development expenses ................................................... 107,936 133,362 24%

For the nine months ended September 30, 2025, our research and development expenses were

€133.4 million, as compared to €107.9 million for the nine months ended September 30, 2024, an increase of

€25.4 million, or 24%. This increase was primarily due to an increase in expenses related to our UC program of €8.6

million, or 10%, resulting from our continued progression of our UC clinical program and the Phase 3 induction

trials data read-out during the third quarter of 2025, an increase in expenses related to our CD program of €5.4

million, or 88%, resulting from the progression of our Phase 2b trials in CD, an increase in expenses related to new

indications (including the combination therapy) for obefazimod of €6.0 million, or 1,930% and an increase in

expenses related to transversal activities of €5.9 million, or 41%, mainly due to increased chemistry, manufacturing

and controls ("CMC") & supply chain costs related to the progression of clinical trials and anticipation of future

commercial launch.

In addition, a sharp rise in employer tax and social contributions related to our stock-based compensation

("AGAs"), in turn attributable to the increase in our share price during the third quarter of 2025, contributed to the

overall increase in research and development expenses across all destinations  for the nine months ended September

30, 2025 as compared to the nine months ended September 30, 2024, in an amount of €14.8 million (of which €14.5

million was attributable to the three-months ended September 30, 2025).

General and Administrative Expenses

(In thousands of euros) Nine Months<br><br>Ended September<br><br>30, 2024 Nine Months Ended<br><br>September 30, 2025 % Change
Personnel costs .......................................................................... 15,483 31,588 104%
Consulting and professional fees ............................................... 6,077 7,245 19%
Other general and administrative expenses ............................... 3,746 2,971 (21)%
General and administrative expenses .................................... 25,306 41,803 65%

For the nine months ended September 30, 2025, our general and administrative expenses were

€41.8 million, as compared to €25.3 million for the nine months ended September 30, 2024, an increase of

€16.5 million, or 65%. This increase was primarily due to a €16.1 million, or 104%, increase in personnel costs,

attributable to the increase in employer tax and social contributions related to our AGAs of €15.1 million (of which

€14.8 million was attributable to the three-months ended September 30, 2025), resulting from the increase in our

share price during the third quarter of 2025, and to a lesser degree by an increase in consulting and professional fees

by €1.2 million, or

19%

, driven by an increase in legal and professional fees and costs associated with operating as a

dual-listed public company. The increase was partly offset by a €0.9 million, or (24)%, decrease in other general and

administrative expenses.

16

Operating Loss

For the nine months ended September 30, 2025, our net operating loss was €174.4 million, as compared to

a net operating loss of €130.2 million for the nine months ended September 30, 2024, an increase of €44.2 million,

or 34%. This increase was primarily due to an increase of €25.4 million in research and development expenses and

to an increase of €16.5 million in general and administrative expenses, partially offset by a decrease of €1.7 million

in sales and marketing expenses.

The overall increase in our operating loss was primarily driven by employer tax and social contributions

related to our AGAs, due to the increase in our share price during the third quarter of 2025, amounting to €30.9

million for the nine-months ended September 30, 2025, as compared to €0.6 million for the nine-months ended

September 30, 2024, an increase of €30.2 million (of which €29.6 million was attributable to the third quarter of

2025).

Financial Loss

For the nine months ended September 30, 2025, our financial loss was €79.7 million, as compared to a

financial loss of €6.7 million for the nine months ended September 30, 2024.

For the nine months ended September 30, 2025, our financial loss of €79.7 million was mainly driven by (i)

increases in the fair values of the senior convertible notes (the "Heights Convertible Notes") issued pursuant to the

subscription agreement entered into in August 2023 with entities affiliated with Heights Capital Management (the

"Heights Financing") and the  warrants issued in August 2023 to Kreos Capital and Claret European Growth Capital

(the “Kreos / Claret BSA") of €36.0 million and €29.9 million, respectively (predominantly driven by the increase in

our share price and the remeasurement of these instruments prior to their conversion into ordinary shares), (ii)

foreign exchange losses of €11.4 million (including the

€9.1

million non-cash impact of the revaluation of U.S.

dollar-denominated cash and cash equivalents as of September 30, 2025), (iii) interest expenses of €9.3 million in

relation to the first tranche of senior secured convertible bonds with warrants attached issued in the Kreos / Claret

Financing (the “Kreos / Claret OCABSA”), the second and third tranches of senior secured bonds issued in the

Kreos / Claret Financing and the Heights Convertible Notes, and (iv) a non-cash expense of €15.6 million in relation

to our royalty certificates.

These expenses were partially offset mainly by (i) foreign exchange gains of €11.7 million (including the

€10.7 million gain related to our July 2025 Nasdaq Offering), (ii) non cash-income of €3.6 million related to the

extinguishment of the Kreos / Claret minimal return indemnifications liability (following the exercises of the Kreos /

Claret BSA and the conversion of the Kreos OCABSA) and (iii) interest income of €4.4 million in relation to the

invested proceeds from our U.S. initial public offering on Nasdaq, our debt financings and our July 2025 Nasdaq

Offering.

For the nine months ended September 30, 2024, our financial loss of €6.7 million was mainly driven by (i)

interest expenses of €7.8 million in relation to the first tranche of the Kreos / Claret OCABSA  issued in the Kreos /

Claret Financing, the second and third tranches of senior secured bonds issued in the Kreos / Claret Financing

(drawn on March 28, 2024 and June 21, 2024, respectively) and the Heights Convertible Notes, (ii) a non-cash

expense of €3 million in relation to our royalty certificates, (iii) €2.2 million in foreign exchange gains, (iv) a €1.2

million increase in the fair value of derivatives and (v) transaction costs of €1.6 million  related to the drawdown of

the second and third tranches of the Kreos / Claret Financing.

These expenses were partially offset mainly by (i) interest income of €6.8 million in relation to the invested

proceeds from our U.S. initial public offering and (ii) foreign exchange gains of €2.1 million.

Income Taxes

For each of the nine months ended September 30, 2024 and 2025, we had no income tax charge.

17

Net Loss

For the nine months ended September 30, 2025, our net loss was €254.1 million, as compared to

€136.9 million for the nine months ended September 30, 2024, an increase of €117.3 million, or 86%, mainly driven

by an increase in operating expenses of €40.2 million of and an increase in financial loss of €73.1 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 losses for the foreseeable future and may never become profitable. For the nine-month periods ended

September 30, 2024 and 2025, we reported net losses of €136.9 million and €254.1 million, respectively. As of

December 31, 2024, we carried forward accumulated tax losses of €609.4 million.

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

proceeds of €1,194.7 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 Nasdaq Offering, bank borrowings and structured loans of €175.0 million, reimbursements of

CIR in an amount of €41.3 million, subsidies 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 value of €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 our existing cash and cash equivalents of €589.7 million as of September 30, 2025, we expect, as of

the date of issuance of the unaudited interim condensed consolidated financial statements included in this quarterly

report, to be able to fund our forecasted cash flow requirements into the fourth quarter of 2027, allowing us to reach

12 months of expected cash runway post the planned new drug application ("NDA") submission for UC, assuming

positive results from its Phase 3 maintenance trial. Our forecasted cash flow requirements take into account our

assumption of continued R&D expenditure related to the continuation of the Phase 3 clinical trials of obefazimod in

UC, progression of the Phase 2b clinical trials for CD and the initial stages of the scale up of the commercial

organization as we prepare for a potential launch of obefazimod in UC.

Based on the above, management has concluded that its existing cash and cash equivalents are sufficient to

fund its operating and capital expenditure requirements for a period greater than 12 months from the date of issuance

of the financial statements accompanying this quarterly 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).

Research Tax Credits

From our inception to September 30, 2025, we have benefited from refunds of CIRs in a total amount of €41.3

million. In November 2024, we received CIRs of €4.5 million with respect to the year ended December 31, 2023. In

June 2025, we received CIRs of €5.7 million with respect to the year ended December 31, 2024.

18

Bpifrance—Conditional Advances and Subsidies

We have received several conditional advances and subsidies from Bpifrance since our inception. Funds

received from Bpifrance in the form of conditional advances are recognized as financial liabilities, as we have a

contractual obligation to reimburse Bpifrance for such conditional advances in cash based on a repayment schedule.

Each award of an advance is made to help fund a specific development milestone. Subsidies are non-repayable

grants, which are recognized in the financial statements when there exists reasonable assurance that we will comply

with the conditions attached to the subsidies and the subsidies will be received.

Bpifrance—CARENA Contract

As part of the development of therapeutic and diagnostic solutions targeting alternative splicing and RNA

interference in the fields of virology (HIV-AIDS, HTLV-1) and metabolism (obesity), SPLICOS, which we acquired

in October 2014, entered into a Master Support Agreement and a conditional advance contract in December 2013 for

the “CARENA” Strategic Industrial Innovation Project (“CARENA project”), with Bpifrance. Under this contract,

we were eligible to receive up to €3.8 million in conditional advances to develop a therapeutic HIV treatment

program with obefazimod. As of December 31, 2024 (year during which the program was terminated), we had

received €3.4 million of conditional advances and subsidies in total.

In June 2024, the Company and Bpifrance agreed to terminate the project due to technical failure.

Bpifrance granted an additional amount of €1.1 million payable to the Company to reimburse additional expenses

incurred as part of the project, and agreed to waive 60% of the remaining conditional advance of €3.3 million and

accrued interests, for which we recognized a subsidy income of €2.3 million in the aggregate. We repaid the

outstanding amounts during the second half of 2024.

Bpifrance—RNP-VIR Contract

As part of the CARENA project, focused on the clinical development of a drug molecule and demonstrating

the validity of an innovative therapeutic approach targeting viral RNPs, we entered into a Master Support

Agreement with Bpifrance, as well as a beneficiary agreement dated March 21, 2017, with conditional advances for

the “RNP-VIR” structuring research and development project for competitiveness. Under the RNP-VIR contract, we

were eligible to receive up to €6.3 million in conditional advances to develop methods for the discovery of new

molecules for the treatment of viral infectious diseases through the development of the “Modulation of RNA

biogenesis” platform. As of December 31, 2024 (year during which the program was terminated), we had received

€3.9 million of conditional advances and subsidies in total.

In June 2024, the Company and Bpifrance agreed to terminate the project due to technical failure.

Bpifrance claimed the reimbursement of €1.2 million corresponding to overpayments of conditional advances and

subsidies (for which the Group had not incurred the corresponding R&D expenses) and agreed to waive 60% of the

remaining advances of €3.0 million and accrued interests, for which the Group recognized a subsidy income of €1.9

million in the aggregate. We repaid the outstanding amounts during the second half of 2024.

Bpifrance—Ebola

The Bpifrance and Occitanie Region joint support agreement was entered into on June 2, 2017 and provides

for conditional advances for a total amount of €0.4 million (€0.1 million from the Languedoc Roussillon Midi

Pyrénées Region and €0.3 million from Bpifrance) for the Ebola program. All funds under this contract were

received. In September 2019, we terminated this program due to the imminent licensing of a competing vaccine for

this indication, as well as changes in the macroeconomic climate for public funding. The reimbursement of the

conditional advance was spread over the period from September 2019 to June 2024.

Indebtedness

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

2024 Annual Report on Form 20-F.

During the nine-month period ended September 30, 2025, we did not enter into any new financing agreements.

On July 23 and July 30, 2025, we received notices from entities affiliated with Heights Capital Management,

which hold the Heights Convertible Notes, for the conversion of 150 and 200 convertible notes (corresponding to the

19

entirety of the outstanding principal amount of €21.9 million) into an aggregate of 920,377 new ordinary shares of

the Company at a conversion price of €23.7674 per ordinary share in accordance with the terms and conditions of

the convertible notes. Following these share issuances, we no longer hold any debt with Heights Capital

Management.

On August 6, 2025, Kreos Capital VII(UK) Limited converted its Tranche A portion (OCABSA) of the

Kreos / Claret Financing Agreement, resulting in the issuance of 785,389 ordinary shares if the Group. In addition,

on the same date, Kreos Capital VII Aggregator SCSp exercised all of its share warrants (the tranche A-B BSA and

tranche C BSA) resulting in the issuance of 319,251 ordinary shares of the Company.

On August 28, 2025, Claret European Growth Capital Fund III SCSp exercised its share warrants (the

tranche A-B BSA and tranche C BSA) resulting in the issuance of 206,662 shares of the Company.

Historical Changes in Cash Flows

The following table sets forth our cash inflows and outflows for the nine-month periods ended September 30,

2024 and 2025.

(In thousands of euros) Nine Months<br><br>Ended September<br><br>30, 2024 Nine Months<br><br>Ended September<br><br>30, 2025 % Change
Net cash flows used in operating activities ............................................ (120,558) (137,901) 14%
Net cash flows provided by investing activities ................................... 15,206 4,549 (70)%
Net cash flows provided by financing activities .................................... 34,033 586,857 1,624%
Effect of movements in exchange rates on cash held ............................ (171) (8,940) 5,117%
Revaluation of cash equivalents measured at fair value ........................ 916 —%
Net increase (decrease) in cash and cash equivalents  ..................... (71,491) 445,481 (723)%
Cash and cash equivalents at the beginning of the period ............... 251,942 144,221 (43)%
Cash and cash equivalents at the end of the period .......................... 180,451 589,703 227%

Operating Activities

For the nine months ended September 30, 2025, cash used in operating activities was €137.9 million, as

compared to €120.6 million for the nine months ended September 30, 2024, an increase of €17.3 million, or 14%.

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, from €(2.8) million for the nine months ended

September 30, 2024 to €13.4 million for the nine months ended September 30, 2025.

Investing Activities

For the nine months ended September 30, 2025, cash provided by investing activities was €4.5 million and

was mainly due to interest received of €4.6 million.

For the nine months ended September 30, 2024, cash provided by investing activities was €15.2 million and

was mainly due to a decrease in deposits of €9.1 million from the payment of the Group's 6-month term deposit and

interest received of €6.9 million.

Financing Activities

For the nine months ended September 30, 2025, cash provided by financing activities was €586.9 million,

which primarily consisted of net proceeds from our July 2025 Nasdaq Offering of €608.1 million, partially offset by

20

repayments of €18 million (of which €14.6 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 State-guaranteed loan (Prêt garanti par

l'Etat, or "PGE")) and interest payments of €5.4 million.

For the nine months ended September 30, 2024, cash provided by financing activities was €34.0 million,

which consisted of drawdowns on tranche B (in an amount of €25 million) and tranche C (in an amount of €25

million) of the senior secured non-convertible bonds from the Kreos / Claret Financing, net of disbursed transaction

costs and deposits (in an amount of €2.1 million in the aggregate), partially offset by repayments of €7.8 million (of

which €6.6 million under the Heights Notes) and interest payments of €5.4 million.

Material Cash Requirements

Contractual Obligations and Loans

The following table sets forth aggregate information about material contractual obligations as of September

30, 2025.

The commitment 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.

As of September 30, 2025 As of September 30, 2025 As of September 30, 2025
Less than More than
(In thousands of euros) 1 year 1 year Total
Financial debt obligations ................... 31,500 19,669 51,169
Lease obligations ................................. 980 766 1,746
Retirement benefits ............................. 0 844 844
Off-balance sheet obligations .............. 182,597 0 182,597
Total .................................................... 215,077 21,279 236,356

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

or subcontractors who conduct clinical trials and studies in relation to the 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.

Our material cash requirements in the above table do not include potential future royalty payments related to

the royalty certificates, amounting to 2% of the future net sales of obefazimod (worldwide and for all indications).

The amount of royalties that may be paid under the royalty certificates is capped at €172.0 million in the aggregate.

Royalty payments are expected to take place before the expiry date of the certificates, which is 15 years after their

issuance date (September 2, 2037).

As of September 30, 2025, our contractual obligations and loans were

€236.4

million, comprising financial

debt obligations of

€51.2

million (in turn, comprising €40.2 million with respect to the second and third tranches of

senior secured non-convertible bonds in the Kreos / Claret Financing, €9.7 million with respect to the Claret

OCABSA and €1.3 million with respect to the PGE), lease obligations of

€1.7

million, retirement benefits

obligations of

€0.8

million and off-balance sheet obligations of

€182.6

million with respect to purchase obligations.

F-1

INDEX TO UNAUDITED INTERIM CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

Condensed Consolidated Statements of Financial Position ............................................................... F-2
Condensed Consolidated Statements of Loss .................................................................................... F-3
Condensed Consolidated Statements of Comprehensive Loss .......................................................... F-4
Condensed Consolidated Statements of Changes in Shareholders’ Equity ....................................... F-5
Condensed Consolidated Statements of Cash Flows ......................................................................... F-6
Notes to the Condensed Consolidated Financial Statements ............................................................. F-7

F-2

ABIVAX SA UNAUDITED INTERIM CONDENSED CONSOLIDATED STATEMENTS OF FINANCIAL

POSITION

(Amounts in thousands of euros) Notes AS OF<br><br>DECEMBER 31, 2024 AS OF<br><br>SEPTEMBER 30,<br><br>2025
ASSETS
Non-current assets
Goodwill 6 18,419 18,419
Intangible assets 7 6,606 6,606
Property, plant and equipment 8 2,666 1,914
Other financial assets 9 5,919 5,102
Other receivables and assets 10 948 717
Total non-current assets 34,558 32,757
Current assets
Other financial assets 9 7,554 9,171
Other receivables and assets 10 18,896 20,421
Cash and cash equivalents 11 144,221 589,703
Total current assets 170,671 619,295
TOTAL ASSETS 205,228 652,052
LIABILITIES AND SHAREHOLDERS' EQUITY
Shareholders’ equity
Share capital 633 778
Premiums related to share capital 478,905 1,179,528
Translation reserve (75) 743
Retained earnings (262,637) (415,669)
Net loss for the period (176,242) (254,142)
Total shareholders’ equity 13 40,584 511,238
Non-current liabilities
Retirement benefit obligations 16 756 844
Provisions 14 819 16,622
Borrowings 15 29,056 12,390
Convertible loan notes 15 23,370 4,099
Derivative instruments 15 3,620
Royalty certificates 15 13,023 28,099
Total non-current liabilities 70,645 62,053
Current liabilities
Borrowings 15 22,195 25,230
Convertible loan notes 15 21,574 4,170
Derivative instruments 15 1,166
Provisions 14 532 11,412
Trade payables and other current liabilities 17.1 43,824 30,019
Tax and employee-related payables 17.2 4,709 7,931
Total current liabilities 93,999 78,761
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY 205,228 652,052

F-3

ABIVAX SA UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF LOSS

(Amounts in thousands of euros, except per<br><br>share amounts) Notes FOR THE<br><br>THREE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2024 FOR THE<br><br>THREE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2025 FOR THE NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2024 FOR THE NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2025
Other operating income 18 1,324 2,043 8,139 4,130
Total operating income 1,324 2,043 8,139 4,130
Sales and marketing 19.1 (853) (1,838) (5,082) (3,372)
Research and development 19.2 (43,286) (55,416) (107,936) (133,362)
General and administrative 19.3 (7,375) (25,500) (25,306) (41,803)
Total operating expenses (51,514) (82,755) (138,325) (178,538)
Operating loss (50,189) (80,712) (130,186) (174,407)
Financial expenses (8,474) (93,051) (16,627) (102,478)
Financial income 3,436 20,404 9,949 22,743
Financial gain (loss) 21 (5,037) (72,647) (6,679) (79,735)
Net loss before tax (55,227) (153,358) (136,864) (254,142)
Income tax 22
Net loss for the period (55,227) (153,358) (136,864) (254,142)
Weighted average number of outstanding<br><br>shares used for computing basic/diluted loss<br><br>per share 63,226,066 72,944,298 63,024,814 66,634,630
Basic / diluted loss per share (€/share) 23 (0.87) (2.10) (2.17) (3.81)

F-4

ABIVAX SA UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE

LOSS

(Amounts in thousands of euros) Notes FOR THE<br><br>THREE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2024 FOR THE<br><br>THREE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2025 FOR THE<br><br>NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2024 FOR THE<br><br>NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2025
Net loss for the period (55,227) (153,358) (136,864) (254,142)
Items that will not be reclassified to profit or<br><br>loss (9) 4 56 40
Actuarial gains and losses on retirement benefit<br><br>obligations 16 (9) 4 56 40
Items that are or may be reclassified<br><br>subsequently to profit or loss 185 260 104 818
Foreign currency translation differences 185 260 104 818
Other comprehensive income (loss) 175 264 161 858
Total comprehensive income (loss) for the<br><br>period (55,051) (153,095) (136,704) (253,284)

F-5

ABIVAX SA UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS’ EQUITY

(In thousands of euros, except number of<br><br>shares) NUMBER OF<br><br>SHARES<br><br>ISSUED SHARE<br><br>CAPITAL PREMIUMS<br><br>RELATED TO<br><br>SHARE<br><br>CAPITAL TRANSLATION<br><br>RESERVE RETAINED<br><br>EARNINGS NET LOSS<br><br>FOR THE<br><br>YEAR TOTAL<br><br>SHAREHOLDER<br><br>S' EQUITY
AS OF<br><br>JANUARY 1, 2024 62,928,818 629 478,218 112 (135,210) (147,740) 196,009
Net loss for the period (136,864) (136,864)
Other comprehensive income (loss) 16 104 56 161
Total comprehensive loss for the period 104 56 (136,864) (136,704)
Appropriation of prior period net loss (147,740) 147,740
Transaction costs related to capital increase 13.2 446 446
Issue of share warrants 200 200
Exercises of other share warrants 4,000 45 45
Issue of free shares 361,835 4 (4)
Shares based compensation expense 15,767 15,767
Transactions on treasury shares 120 120
AS OF<br><br>SEPTEMBER 30, 2024 13.1 63,294,653 633 478,905 217 (267,007) (136,864) 75,883
AS OF<br><br>JANUARY 1, 2025 63,347,837 633 478,905 (75) (262,637) (176,242) 40,584
Net loss for the period (254,142) (254,142)
Other comprehensive income (loss) 16 818 40 858
Total comprehensive loss for the period 818 40 (254,142) (253,284)
Appropriation of prior period net loss (176,242) 176,242
Capital increase from issuance of ordinary<br><br>shares 13.2 11,679,400 117 637,345 637,462
Transaction costs related to capital increase 13.2 (40,264) (40,264)
Issue of share warrants 14 300 300
Exercises of the Kreos/Claret share warrants 13.2, 15.1 525,913 5 33,763 33,768
Exercises of other share warrants 13.2, 14 24,246 193 193
Conversion of the Kreos OCABSA 15.1 785,389 8 15,380 673 16,062
Conversion of the Heights notes 15.2 920,377 9 53,912 53,921
Issue of free shares 14 546,905 5 (5)
Shares based compensation expense 14 22,497 22,497
AS OF<br><br>SEPTEMBER 30, 2025 13.1 77,830,067 778 1,179,528 743 (415,669) (254,142) 511,238

F-6

ABIVAX SA UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(Amounts in thousands of euros) Notes FOR THE NINE<br><br>MONTHS ENDED<br><br>SEPTEMBER 30, 2024 FOR THE NINE<br><br>MONTHS ENDED<br><br>SEPTEMBER 30, 2025
Cash flows provided by (used in) operating activities
Net loss for the period (136,864) (254,142)
Adjustments for:
Elimination of amortization of intangibles and depreciation of property,<br><br>plant and equipment 821 796
Elimination of retirement benefit obligations 16 47 106
Elimination of share-based compensation expenses 14 15,767 22,497
(-) Net gain on sale of treasury shares (16)
Interest expenses and other financial expenses 21 14,659 36,463
Financial income 21 (9,169) (18,866)
Effect of unwinding the discount related to advances 21 (520) (536)
Increase/(decrease) in derivatives and liabilities measured at fair value 15 1,691 62,330
Forgiveness of conditional advances 17 (4,140)
Other (73) 65
Cash flows provided by (used in) operating activities before change in<br><br>working capital requirements (117,797) (151,287)
Decrease / (increase) in other receivables and related accounts 1,365 (2,301)
Increase / (decrease) in trade payables (3,613) (14,260)
Increase / (decrease) in tax and social security liabilities (574) 3,428
Change in provisions, deferred income and other liabilities 61 26,519
Changes in working capital requirements (2,761) 13,386
Cash flows provided by (used in) operating activities (120,558) (137,901)
Cash flows provided by (used in) investing activities
Acquisitions of intangible assets (3)
Acquisitions of property, plant and equipment (547) (55)
Advances reimbursed by / (made to) CROs 10 80
Increase in deposits 9 (212) (230)
Decrease in deposits 9 9,050 120
Interest received 6,919 4,634
Cash flows provided by (used in) investing activities 15,206 4,549
Cash flows provided by (used in) financing activities
Capital increases 13 648,124
Repayments / (payments) related to capital increase 13 446 (40,042)
Net proceeds from non-convertible bond loans 15 47,944
Exercise of warrants 15 2,667
Repayments of non-convertible bond loans 15 (14,551)
Repayments of convertible loan notes 15 (6,563) (2,188)
Repayment of PGE 15 (1,250) (1,250)
Net proceeds from sale of treasury shares 120
Repayments of conditional advances 15 (1,142)
Payments of the lease liabilities 15 (403) (782)
Interest paid 15 (5,364) (5,422)
Other 245 300
Cash flows provided by (used in) financing activities 34,033 586,857
Effect of movements in exchange rates on cash held 11 (171) (8,940)
Revaluation of cash equivalents measured at fair value 11 & 21 916
Increase (decrease) in cash and cash equivalents (71,491) 445,481
Cash and cash equivalents at the beginning of the year 11 251,942 144,221
Cash and cash equivalents at the end of the year 11 180,451 589,703
Increase (decrease) in cash and cash equivalents (71,491) 445,481

F-7

ABIVAX SA NOTES TO THE UNAUDITED INTERIM CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

Note 1. The Group

Note 1.1. Information on the Group and its business

ABIVAX SA (the “Company”) is a société anonyme incorporated under the laws of France on December 4, 2013. Its registered office

is located at 7-11 Boulevard Haussmann—75009 Paris, France. The Company is developing therapeutics designed to harness the

body’s natural regulatory mechanisms to stabilize the immune response in patients with chronic inflammatory diseases.

These unaudited interim condensed consolidated financial statements as of and for the three- and nine-month periods ended

September 30, 2025 comprise the Company and ABIVAX LLC (the “Subsidiary”), the United States subsidiary of ABIVAX SA,

created on March 20, 2023 under the laws of the State of Delaware (together referred to as the “Group”).

The Group has incurred losses since its inception and had shareholders’ equity of €511,238 thousand as of September 30, 2025. The

Group anticipates incurring additional losses until such time, if ever, that it can generate significant revenue from its drug candidates

which are currently under development. Substantial additional financing will be needed by the Group to fund its operations and to

commercially develop its drug candidates, if approved. See note 3.3. Subsequent event.

The Group's future operations are highly dependent on a combination of factors, including: (i) the success of its research and

development activities; (ii) regulatory approval and market acceptance of its proposed future products; (iii) the timely and successful

completion of additional financing and (iv) the development of competitive therapies by other biotechnology and pharmaceutical

companies. As a result, the Group is, and expects to continue to be, in the short to mid-term, financed through the issuance of new

equity or debt instruments.

The Group is focusing its efforts on the following points:

•Continuation of the Phase 3 clinical trial program (ABTECT) for obefazimod in moderately to severely active ulcerative

colitis (“UC”).

•Continuation of the Phase 2b clinical trial (ENHANCE-CD) of obefazimod in Crohn’s disease (“CD”).

•Evaluating oral or injectable combination therapy candidates with obefazimod in UC.

•Selecting a follow-on candidate for obefazimod.

Note 1.2. Date of authorization of issuance

The unaudited interim condensed consolidated financial statements and related notes have been prepared under the responsibility of

management of the Group and were approved and authorized for issuance by the Group’s board of directors on December 15, 2025.

Note 2. Basis of preparation

Except for share data and per share amounts, the unaudited interim condensed consolidated financial statements are presented in

thousands of euros. Amounts are rounded up or down the nearest whole number for the calculation of certain financial data and other

information contained in these accounts. Accordingly, the total amounts presented in certain tables may not be the exact sum of the

preceding figures.

F-8

Statement of compliance

These unaudited interim condensed consolidated financial statements as of September 30, 2025 and for the three- and nine-month

periods ended September 30, 2025 and 2024 have been prepared in accordance with IAS 34 “Interim Financial Reporting” as issued

by the International Accounting Standards Board ("IASB") and as adopted by the European Union (EU) and should be read in

conjunction with the latest Group’s annual financial statements for the years ended December 31, 2022, 2023 and 2024, prepared in

accordance with the International Financial Reporting Standards ("IFRS") as issued by IASB and as adopted by the EU.

They do not include all the information required for a complete set of financial statements prepared under IFRS. They do, however,

include selected notes explaining significant events and transactions in order to understand the changes in the Group’s financial

position and performance since the last annual financial statements.

The accounting policies used to prepare these unaudited interim condensed financial statements are identical to those applied by the

Group as of December 31, 2024, except for:

•the texts whose application is compulsory as from January 1, 2025;

•the specific provisions of IAS 34 used in the preparation of the unaudited interim condensed consolidated financial

statements.

The application of the new Amendments to IAS 21 "The Effects of Changes in Foreign Exchange Rates – Lack of Exchangeability" is

mandatory for annual reporting periods beginning on or after January 1, 2025. The Group concluded that these issued accounting

pronouncements are not applicable for the periods presented.

The standards and interpretations not yet mandatory as of September 30, 2025 are the following:

•Amendments to IFRS 9 Financial Instruments and IFRS 7 Financial Instruments: Disclosures – Amendments to the

Classification and Measurement of Financial Instruments, whose application is for annual reporting periods beginning on or

after January 1, 2026, as approved by the EU on May 27, 2025;

•Amendments to IFRS 9 Financial Instruments and IFRS 7 Financial Instruments: Disclosures – Contracts Referencing

Nature-dependent Electricity, whose application is for annual reporting periods beginning on or after January 1, 2026, as

approved by the EU on June 30, 2025;

•IFRS 18 Presentation and Disclosure in Financial Statements, whose application is for annual reporting periods beginning on

or after January 1, 2027 (not yet approved by the EU);

•IFRS 19 Subsidiaries without Public Accountability: Disclosures, whose application is for annual reporting periods beginning

on or after January 1, 2027 (not yet approved by the EU), and

•Annual Improvements Volume 11, whose application is for annual reporting periods beginning on or after January 1, 2026, as

approved by the EU on July 9, 2025.

These texts have not been early adopted. The expected impacts are not considered significant, except for IFRS 18, for which the Group

has not completed its assessment to date.

Preparation of the financial statements

The unaudited interim condensed consolidated financial statements of the Group were prepared on a historical cost basis, with the

exception of certain asset and liability categories and in accordance with the provisions set out in IFRS such as employee benefits

measured using the projected unit credit method, the Heights notes (classified under "Convertible loan notes") measured at fair value

and derivative financial instruments measured at fair value.

F-9

Going concern

The Group has incurred substantial operating losses since inception and expects to continue to incur significant operating losses for the

foreseeable future and may never become profitable. For the nine-month period ended September 30, 2025, the Group had a net loss

of -254.1 million.

Since inception, the Group has financed its operations through the issuance of ordinary shares with gross aggregate proceeds of

€1,194.7 million, of which €130 million of gross proceeds were from offerings of its ordinary shares on Euronext Paris in February

2023, €223.3 million of gross proceeds were from its offering of ordinary shares in the form of American Depository Shares ("ADS")

on the Nasdaq Global Market as well as ordinary shares in Europe (including France) and countries outside of the United States in a

private placement in October 2023 and €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 Offering"), bank borrowings and structured loans for €175.0 million,

reimbursements of CIR in an amount of €41.3 million, subsidies 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.

Based on the Group’s existing cash and cash equivalents of €589.7 million as of September 30, 2025, the Group expects, as of the date

of issuance of these financial statements, to be able to fund its forecasted cash flow requirements into the fourth quarter of 2027,

allowing it to reach 12 months of expected cash runway following the planned NDA submission for UC in the second half of 2026,

assuming positive results from its Phase 3 maintenance trial. This takes into account management's assumptions of continued R&D

expenditure related to the continuation of the Phase 3 clinical trials of obefazimod in UC, progression of the Phase 2b clinical trials for

CD and the initial stages of the scale up of the commercial organization as the Group prepares for a potential launch of obefazimod in

UC.

Based on the above, these financial statements have been prepared on a going concern basis.

Impact of the Ukraine/Russia Hostilities on the Group

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, the Group has decided not to include Russia and Belarus in its global Phase 3 program for obefazimod in

UC. However, the global scale of this conflict cannot be predicted at this stage. The Group, therefore, cannot rule out an adverse

impact of this conflict on its business, including in terms of access to raw materials, logistics, the performance of clinical studies and

in relation to any future financing the Group may seek.

The long-term safety and efficacy extension of the Phase 2b maintenance trial of obefazimod in moderately to severely active UC is

the Group’s only clinical trial with patients currently enrolled in Ukraine. The Phase 2b 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. The Group also has a few Ukrainian sites active in the western part of Ukraine

in the ABTECT Phase 3 clinical trials. 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. The Group continues to monitor developments in the region, but any

instability as a result of the war may have material adverse impacts on these clinical sites, which could negatively impact our Phase 3

clinical trials.

Together with its contract research organizations ("CROs"), the Group is 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.

F-10

Note 3. Significant events for the year ended December 31, 2024 and the nine-month period ended September 30, 2025 and

subsequent events

Note 3.1. For the year ended December 31, 2024

Changes in management – February-December 2024

On February 7, 2024, the Group announced the appointment of Ana Sharma as Vice President, Global Head of Quality. Ms. Sharma

left the Group in November 2024.

On April 2, 2024, the Group announced the appointment of Camilla Soenderby as Independent Board Member and also a member of

the Appointments and Compensation Committee. Ms. Soenderby replaces Santé Holdings S.R.L., represented by Mr. Paolo Rampulla,

who will continue to contribute to the work of the Board of Directors as an observer alongside Mr. Maurizio PetitBon from Kreos

Capital/Blackrock.

In July 2024, the Group announced the appointment of Sylvie Grégoire as Independent Board Member, Chairman of the Board and

also a member of the Audit Committee. Ms. Grégoire replaces Ms. Brosgart as Director, Mr. de Garidel as Chairman, and Mr. Hong as

member of the Audit Committee. As the Group entered into the final stages of the ABTECT program and prepared to commence the

Phase 2b ENHANCE-CD trial, Dr. Fabio Cataldi was appointed as Chief Medical Officer, taking over from Dr. Sheldon Sloan, MD,

M Bioethics. Additionally, David Zhang, Ph.D joined the Group as Chief Strategy Officer. Dr. Zhang has internal responsibility for

Biometrics, Quality, HEOR and Regulatory. Finally, the Group also announced that Chief Commercial Officer Michael Ferguson has

left the organization to pursue other opportunities.

On November 13, 2024, the Group announced the appointment of Mark Stenhouse as Board Observer & Advisor to the Group.

On December 23, 2024, the Group announced the resignation of Dr. Philippe Pouletty, representative of Truffle Capital, as director of

the Group, effective on December 31, 2024.

Share-based compensation plans – February-September 2024

In February, March, May, July and September 2024, the Group issued seven free-share compensation plans to certain of its officers

and employees, representing a maximum of 1,946,125 shares in the aggregate, the vesting of which is subject to the following service

condition: 50% of the AGAs vest at the end of a two-year period from the allocation date, 25% at the end of a three-year period from

the allocation date and 25% at the end of a four-year period from the allocation date (with the exception of the 20,000 2024-6 AGAs,

whose vesting conditions are set forth in Note 14).

In March 2024, the Group granted its independent Board members the right to subscribe up to

77,820

share warrants (BSA) in the

aggregate, the vesting of which is subject to a service condition of four years, by tranches of 25% each, vested on each anniversary

date. All the BSAs have been subscribed.

The detailed terms and conditions and the accounting treatment of these plans are presented in Note 14 to the annual consolidated

financial statements of the Group as of December 31, 2024 accompanying the Group’s annual report on Form 20-F for the year ended

December 31, 2024 filed with the Securities and Exchange Commission on March 24, 2025 (the “Annual Report”).

Drawdown of Tranches B and C of the Kreos / Claret Financing – March-June 2024

On March 28, 2024 and June 21, 2024, the Group drew down €25 million related to tranche B and €25 million related to tranche C of

senior secured non-convertible bonds from the Kreos / Claret Financing.  These second and third tranches each consist of 25,000,000

senior secured non-convertible bonds with a par value of €1.00 each, that will not be listed on any market.

The detailed characteristics of these bond loans and their accounting treatments are set forth in Note 15.1 to the annual consolidated

financial statements of the Group as of December 31, 2024 accompanying the Group’s Annual Report.

F-11

Bpifrance RNP-VIR and Carena conditional advances – June 2024

In June 2024, the Group and Bpifrance renegotiated the RNP-VIR and CARENA conditional advances:

•Under the RNP-VIR contract, the Group was eligible to receive up to €6.3 million in conditional advances to further develop

methods for the discovery of new molecules for the treatment of viral infectious diseases through the development of the

“Modulation of RNA biogenesis” platform. Between September 2017 and November 2019, the Group had received repayable

conditional advances amounting €4,032 thousands and subsidies amounting to €1,123 thousand in relation to the RNP-VIR

project.

In June 2024, the Group and Bpifrance agreed to terminate the project due to technical failure. Bpifrance claimed the

reimbursement of €1,241 thousand corresponding to overpayments of conditional advances and subsidies (for which the

Group had not incurred the corresponding R&D expenses) and agreed to waive 60% of the remaining advances of

€2,945 thousand and accrued interests, which resulted in a subsidy income of €1,872 thousand in the aggregate (see Note 18).

The outstanding amount was fully repaid by the Group during the last quarter of 2024.

•Under the CARENA agreement, the Group was eligible to receive up to €3,840 thousand to develop a therapeutic HIV

treatment program with ABX464. Between December 2013 and June 2016, the Group had received repayable conditional

advances amounting €2,187.

In June 2024, the Group and Bpifrance agreed to terminate the project due to technical failure. Bpifrance granted an

additional amount of €1,068 thousand payable to the Group to reimburse additional expenses incurred as part of the project,

and agreed to waive 60% of the remaining conditional advance of €3,255 thousand and accrued interests, which resulted in a

subsidy income of €2,251 thousand in the aggregate (see Note 18). The outstanding amount was fully repaid by the Group

during the last quarter of 2024.

Establishment of an At-the-Market ("ATM") Program on Nasdaq - November 2024

On November 19, 2024, the Group announced the implementation of an At-The-Market program (“ATM Program”) allowing the

Group to issue and sell, including with unsolicited investors who have expressed an interest, ordinary shares in the form of ADSs,

each ADS representing one ordinary share, nominal value €0.01 per share, of the Group, with aggregate gross sales proceeds of up to

$150,000 thousand (subject to French regulatory limits and within the limits of the investors’ requests expressed in the context of the

program), from time to time, pursuant to the terms of an equity distribution agreement with Piper Sandler & Co. (“Piper Sandler”),

acting as sales agent. The timing of any issuances in the form of ADSs will depend on a variety of factors. The ATM Program will be

effective until terminated in accordance with the equity distribution agreement or if ADSs representing the maximum gross sales

proceeds have been sold thereunder. To the extent that ADSs are sold pursuant to the ATM Program, the Group currently intends to

use the net proceeds (after deduction of fees and expenses), if any, of sales of ADSs issued under the ATM Program primarily to fund

the research and development of the Group's product candidates, for working capital and general corporate purposes, at its discretion.

A shelf registration statement on Form F-3, including a base prospectus relating to the Group's securities and an equity distribution

agreement prospectus relating to the ATM Program, was filed with the SEC and went into effect during 2024. The base prospectus

provides for the potential sale of ADSs of the Group with aggregate gross sales proceeds of up to $350,000 thousand (including the

$150,000 thousand covered by the equity distribution agreement prospectus) to grant additional flexibility to the Group in connection

with its financing strategy. The specific terms of any securities to be offered pursuant to the base prospectus will be specified in one or

more prospectus supplements to the base prospectus. As of the date of issuance of these financial statements, the Group has not

utilized the ATM Program.

F-12

Note 3.2. For the nine-month period ended September 30, 2025

Share-based compensation plans – January-August 2025

In January 2025, the Group granted its independent Board members, as well as one of its Board Observers and Advisor, the right to

subscribe up to 125,000 share warrants (BSA) in the aggregate, the vesting of which (if subscribed) is subject to a service condition of

four years, by tranches of 25% each, vested on January 1 of each year.

In February, March, May and August 2025, the Group issued seven free-share compensation plans to certain of its officers and

employees, representing a maximum of 6,276,727 shares in the aggregate, the vesting of which is subject to the following service

condition: 50% of the AGAs vest at the end of a two-year period from the allocation date, 25% at the end of a three-year period from

the allocation date and 25% at the end of a four-year period from the allocation date (with the exception of the 123,102 2025-2 AGAs,

which vest at the end of a two-year period from the allocation date, and the 50,000 2025-5 AGAs , which vest only upon the

achievement of milestones related to clinical studies). Moreover, the vesting of almost half of the 4,319,500 2025-1 AGAs is subject to

the occurrence of a tender offer on the securities issued by the Group and resulting in a change of control of the Group before a certain

date.

In April 2025, the Group granted to one of its Board members the right to subscribe up to 39,370 share warrants (BSA), the vesting of

which is subject to a service condition of four years, by tranches of 25% each, vested on May 1 of each year. The BSAs were

subscribed in May 2025.

The detailed terms and conditions of these plans are set forth in Note 14.

Change in management – April 2025

On April 22, 2025, the Group announced the appointment of Dominik Höchli, MD to the Board of Directors of Abivax, effective

immediately.

Completion of enrollment for the Phase 3 ABTECT trials in patients with moderately to severely active UC - April 2025

On April 29, 2025, the Group announced the completion of enrollment for the Phase 3 ABTECT trials in patients with moderately to

severely active UC.

Publication of positive Phase 3 results from both ABTECT 8-week induction trials investigating obefazimod, in moderate to severely

active UC – July 2025

On July 22, 2025, the Group announced the results of the ABTECT-1 and ABTECT-2 induction trials in patients with moderately to

severely active UC. ABTECT-1 and 2 are global, multicenter, randomized, double-blind, placebo-controlled trials assessing once-

daily oral administration of obefazimod at 25 mg or 50 mg doses in adult patients with moderately to severely active UC. Eligible

participants had inadequate response, loss of response, or intolerance to conventional and/or advanced therapies.  ABTECT-1 and

ABTECT-2 were conducted simultaneously and have enrolled 1,275 patients from over 600 participating clinical trial sites in 36

countries with the intent to satisfy regulatory requirements globally. The ABTECT Program is one of the largest Phase 3 ulcerative

colitis trials ever conducted and includes the largest population of patients with inadequate response to JAK inhibitor therapy.

Results from the ABTECT-1 and ABTECT-2 trials demonstrated that obefazimod met its FDA primary endpoint of clinical remission

at Week 8 in the 50 mg once-daily dose regimens for both trials. Individually, ABTECT-1 showed a placebo-adjusted clinical

remission rate of 19.3% (p<0.0001) and ABTECT-2 demonstrated 13.4% (p=0.0001), each at the 50 mg once-daily dose, with all key

secondary efficacy endpoints being met.

The 25 mg once-daily dose of obefazimod achieved the FDA primary endpoint of clinical remission at Week 8 in ABTECT-1

demonstrating a placebo-adjusted remission rate of 21.4%. While the 25 mg dose did not achieve statistical significance for this

F-13

endpoint in ABTECT-2, it achieved a pooled placebo-adjusted clinical response rate of 28.6%, indicating a strong signal for these

patients to achieve clinical remission with extended treatment in the maintenance trial.

The safety profile of obefazimod remained consistent with prior clinical experience. No new safety signals were observed in either

trial and the treatment was generally well tolerated across both dose groups.

The ABTECT Maintenance Trial (ABX464-107) is ongoing with top-line results expected to report out during the second quarter of

  1. Among the 1,275 patients randomized in the induction trials, 678 achieved clinical response and enrolled into part 1 of the

maintenance trial. The ABTECT program is one of the largest Phase 3 ulcerative colitis trials ever conducted.

Following this announcement and that of its Offering completed on July 28, 2025 (see Completion of a public offering – July 2025

within this section), the Group’s share price increased significantly, from €6.64 as of June 30, 2025, to €57.00 as of July 28, 2025.

At the same time, the Group reassessed the probability of success (“POS”) of obtaining a future market authorization for obefazimod

in UC, to reflect a reduced level of uncertainty following positive Phase 3 results.

The main financial effects of this event on the Group’s financial statements are the following:

•A significant increase in the carrying value of the royalty certificates, measured at amortized cost, reflecting an increase in the

projected probability-weighted cash flows of the instrument, following the reassessment of the POS (see Note 15.6),

•Significant changes in the carrying value of the Group’s financial liabilities measured at fair value through profit or loss, i.e.

the Kreos / Claret BSA, the Kreos / Claret MRI and the Heights convertible notes (the latter as well as the Kreos / Claret BSA

being converted into ordinary shares at the request of the noteholders in July and August 2025, see Conversion of the Heights

convertible notes, Kreos / Claret OCABSA and Kreos / Claret BSA – July-August 2025 below and Notes 15.1 and 15.2),

•Significant changes in the disclosure of the fair values of other financial instruments measured at amortized cost (i.e. the

royalty certificates, the debt components of (i) the Kreos / Claret OCABSA (Tranche A, converted into shares in August

2025) and (ii) Tranche B and C bond loans; these fair value changes are not expected directly to impact the future financial

position and net loss of the Group - see Note 15),

•A significant increase in provisions related to employer contributions on AGAs (the contribution being based on the vesting

date share price - see Note 14).

Conversion of the Heights convertible notes, Kreos OCABSA and Kreos / Claret BSA – July-August 2025

On July 23 and July 30, 2025, the Group received notices from entities affiliated with Heights Capital Management, which hold

amortizing senior convertible notes of the Group issued in August 2023 (the “Height convertible notes”), for the immediate conversion

of respectively 150 and 200 convertible notes (corresponding to the entirety of the oustanding principal amount of €21.9 million) into

920,377 new ordinary shares of the Group at a conversion price of €23.7674 per ordinary share in accordance with the terms and

conditions of the convertible notes.

On August 6, 2025, Kreos Capital VII (UK) Limited converted its portion of the Tranche A of the Kreos / Claret Financing (the Kreos

OCABSA), resulting in the issuance of 785,389 ordinary shares. In addition, on the same date Kreos Capital VII Aggregator SCSp

exercised its share warrants (the tranche A-B BSA and tranche C BSA) resulting in the issuance of 319,251 ordinary shares of the

Group.

On August 28, 2025, Claret European Growth Capital Fund III SCSp exercised its share warrants (the tranche A-B BSA and tranche C

BSA) resulting in the issuance of 206,662 ordinary shares of the Group.

The impacts of these operations on the Group's financial statements are set forth in Note 15.1 and 15.2.

F-14

Completion of a public offering – July 2025

On July 28, 2025, the Group announced the completion of an underwritten public offering of 11,679,400 ADSs (the “Offering”) at a

price of $64.00 per ADS (corresponding to €54.58 per ordinary share, based on the exchange rate of €1.00 = $1.1726 as published by

the European Central Bank on July 23, 2025). The aggregate gross proceeds amounted to approximately $747.5 million, equivalent to

approximately €637.5 million, before deduction of underwriting commissions and estimated expenses, and the net proceeds, after

deducting underwriting commissions and estimated offering expenses, were approximately $700.3 million, equivalent to

approximately €597.2 million. The net cash from the Offering of €608.1 million presented within the Unaudited Condensed Interim

Statements of Cash Flows also includes the effect of a net foreign exchange gain resulting from the favorable change in the euro to

U.S. dollar exchange rate between the closing of the Offering and the date of receipt of funds.

The Group believes that the net proceeds from the Offering, together with its current cash and cash equivalents, will allow it to finance

its operations into the fourth quarter of 2027, allowing it to reach 12 months of expected cash runway following the planned NDA

submission for UC, assuming positive results from its Phase 3 maintenance trial (see Note 2 above "Going concern").

Admission to the CAC Mid 60 and SBF 120 indices - September 2025

Following the annual review of the Euronext Paris indices on September 11, 2025, the Scientific Council of the Indices has decided to

admit the Company to the CAC Mid 60 and SBF 120 indices. This decision took effect on Friday, September 19, 2025, after market

close. The CAC Mid 60 and SBF 120 are key indices on the Euronext Paris exchange, representing mid-sized listed companies and a

broader selection of 120 major securities, respectively.

Note 3.3. Subsequent events

Conversion of the Claret OCABSA - November 2025

On November 25, 2025, Claret European Growth Capital Fund III SCSp converted its portion of the Tranche A portion of the Kreos /

Claret Financing (the Claret OCABSA), resulting in the issuance of 392,695 ordinary shares of the Group. Following this conversion,

the Group no longer holds any debt related to the Tranche A of the Kreos / Claret Financing.

Early redemption of the Kreos / Claret Tranches B and C bond loans - November 2025

On November 28, 2025, the Group notified the bondholders of its intention to prepay in full the outstanding balances of Tranches B

and C of the Kreos / Claret Financing. The transaction is expected to be completed before December 31, 2025. Following this

redemption, the Group would no longer hold any debt related to the entire Kreos / Claret Financing.

F-15

Note 4. Accounting principles

The Group's accounting policies are the same as those described in the annual consolidated financial statements of the Group as of

December 31, 2024 accompanying the Annual Report.

Use of judgments and estimates

In preparing these unaudited condensed consolidated financial statements, management has made judgments and estimates that affect

the application of the Group’s accounting policies and the reported amounts of assets and liabilities, income and expenses. Actual

values may differ from estimated values.

The significant judgments made by management in the application of the Group’s accounting policies and the key sources of

estimation uncertainty are the same as those described in the annual consolidated financial statements of the Group as of December 31,

2024 accompanying the Annual Report.

Measurement of fair values

A number of the Group’s accounting policies require the measurement of fair values, for both financial and non-financial assets and

liabilities.

When measuring the fair value of an asset or a liability, the Group uses market observable data as far as possible. Fair values are

categorized into different levels in a fair value hierarchy based on the inputs used in the valuation techniques as follows.

•Level 1: quoted prices (unadjusted) in active markets for identical assets or liabilities.

•Level 2: inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly

(i.e., prices) or indirectly (i.e., derived from prices).

•Level 3: inputs for the asset or liability that are not based on observable market data (unobservable inputs).

Seasonality of operations

The Group’s operations are not subject to significant seasonality.

Note 5. Segment information

The assessment of the Group’s performance and the decisions about resources to be allocated are made by the chief operating decision

maker, based on the management reporting system of the Group. The Group identified the Chief Executive Officer of the Group as

“Chief operating decision maker”. The Chief operating decision maker reviews on an aggregated basis the incurred expenses for

allocating and evaluating performance of the Group.

The Group operates in a single operating segment: R&D of pharmaceutical products in order to market them in the future.

Substantially all operations, assets, liabilities, and losses of the Group are located in France. As of September 30, 2025, the

Subsidiary’s contributions to the Group’s assets, liabilities and net losses were less than 10%.

F-16

Note 6. Goodwill and impairment test

Goodwill relates to the acquisition of Splicos SAS that occurred in 2014 (i.e., prior to the transition date to IFRS) which was merged

into the Group the same year.

Goodwill from the Splicos SAS acquisition corresponds to the “Modulation of RNA biogenesis / splicing” technological platform,

from which derived the lead drug candidate of the Group: ABX464.

In accordance with IAS 36, goodwill is allocated to groups of cash generating units (CGUs) at a level corresponding to the lead drug

candidates. Thus, goodwill from Splicos SAS is allocated to the ABX464 CGU.

The net carrying amount of Splicos SAS goodwill is €18,419 thousand as of December 31, 2024 and September 30, 2025.

The ABX464 product candidate being currently in development, a clinical trial failure or a failure to obtain a marketing approval

could result in an impairment. As of September 30, 2025, the Group has not identified any indication of impairment loss related to

goodwill, intangible or tangible assets.

Note 7. Intangible assets

Intangible assets are mainly comprised of the intellectual property underlying:

(i)The collaboration and license agreement with the CNRS, Montpellier 2 University and the Curie for which the Group

paid a milestone of €40 thousand in September 2019 as a result of the entry in phase 2 of ABX464.

(ii)Patents acquired through the acquisition of Prosynergia of €6,529 thousand. The patents are not yet amortized, similarly

to licenses, and are included in the ABX464 CGU for impairment test purposes.

Licenses and patents recognized as Intangible assets are not amortized since they are not operating in a manner intended by the

management. As a consequence, and in accordance with IAS 36, those assets were subject to an annual impairment test as of

December 31, 2024, which did not result in any impairment loss. As of September 30, 2025, no indicator of impairment has been

identified.

F-17

(amounts in thousands of euros) LICENSES SOFTWARE PATENTS TOTAL
GROSS VALUES
AS OF DECEMBER 31, 2023 120 24 6,529 6,673
Acquisition 3 3
Disposal
AS OF<br><br>SEPTEMBER 30, 2024 120 27 6,529 6,677
GROSS VALUES
AS OF<br><br>DECEMBER 31, 2024 120 27 6,529 6,677
Acquisition
Disposal
AS OF<br><br>SEPTEMBER 30, 2025 120 27 6,529 6,677 (amounts in thousands of euros) LICENSES SOFTWARE PATENTS TOTAL
--- --- --- --- ---
AMORTIZATION
AS OF<br><br>DECEMBER 31, 2023 (45) (24) (70)
Increase
Disposal
AS OF<br><br>SEPTEMBER 30, 2024 (45) (25) (70)
AS OF<br><br>DECEMBER 31, 2024 (45) (25) (70)
Increase (1) (1)
Disposal
AS OF<br><br>SEPTEMBER 30, 2025 (45) (26) (71) (amounts in thousands of euros) LICENSES SOFTWARE PATENTS TOTAL
--- --- --- --- ---
NET BOOK VALUES
AS OF<br><br>SEPTEMBER 30, 2024 $75 3 6,529 6,607
AS OF<br><br>DECEMBER 31, 2024 $75 3 6,529 6,606
AS OF<br><br>SEPTEMBER 30, 2025 $75 2 6,529 6,606

F-18

Note 8. Property, plant and equipment

The following tables present changes in property, plant and equipment including the right of use of assets (or “ROU”) as of September

30, 2024 and 2025:

(amounts in thousands of euros) BUILDINGS EQUIPMENT FURNITURE<br><br>AND<br><br>COMPUTER<br><br>EQUIPMENT TOTAL OF WHICH<br><br>ROU
GROSS VALUES
AS OF<br><br>DECEMBER 31, 2023 1,346 513 507 2,366 1,262
Acquisition 2,404 161 2,564 2,018
Disposal (1,110) 0 (119) (1,229) (975)
Effect of the change in foreign currency exchange rates (4) (1) (4) (4)
AS OF<br><br>SEPTEMBER 30, 2024 2,636 513 548 0 3,697 0 2,301
AS OF<br><br>DECEMBER 31, 2024 2,818 513 698 0 4,029 0 2,526
Acquisition 80 53 133 52
Disposal (16) (169) (185) (20)
Effect of the change in foreign currency exchange rates (50) (12) (61) (50)
AS OF<br><br>SEPTEMBER 30, 2025 2,849 497 570 0 3,916 0 2,507 (amounts in thousands of euros) BUILDINGS EQUIPMENT FURNITURE<br><br>AND<br><br>COMPUTER<br><br>EQUIPMENT TOTAL OF WHICH<br><br>ROU
--- --- --- --- --- --- --- --- ---
DEPRECIATION
AS OF<br><br>DECEMBER 31, 2023 (837) (387) (265) (1,488) (761)
Increase (659) (26) (114) (799) (591)
Disposal 1,111 104 1,215 975
AS OF<br><br>SEPTEMBER 30, 2024 (385) (413) (275) (1,072) (377)
AS OF<br><br>DECEMBER 31, 2024 (613) (419) (332) (1,363) (575)
Increase (677) (27) (143) (846) (613)
Disposal 16 169 185 20
Effect of the change in foreign currency exchange rates 17 5 23 17
AS OF<br><br>SEPTEMBER 30, 2025 (1,272) (430) (300) 0 (2,002) (1,150) (amounts in thousands of euros) BUILDINGS EQUIPMENT FURNITURE<br><br>AND<br><br>COMPUTER<br><br>EQUIPMENT TOTAL OF WHICH<br><br>ROU
--- --- --- --- --- --- --- --- --- ---
NET BOOK VALUES
AS OF<br><br>SEPTEMBER 30, 2024 2,251 100 274 0 2,625 1,924
AS OF<br><br>DECEMBER 31, 2024 2,205 94 366 0 2,666 1,950
AS OF<br><br>SEPTEMBER 30, 2025 1,576 67 270 0 1,914 1,357

F-19

Right of use assets relate to buildings, vehicles and furniture. The net book value of right of use assets related to buildings amounted to

€1,886 thousand as of September 30, 2024 and €1,304 thousand as of September 30, 2025.

As of September 30, 2025, no indicator of impairment has been identified.

Note 9. Other financial assets

Other financial assets break down as follows:

(amounts in thousands of euros) AS OF<br><br>DECEMBER 31,<br><br>2024 AS OF<br><br>SEPTEMBER 30,<br><br>2025
OTHER FINANCIAL ASSETS
Advances related to CRO contracts 4,929 4,283
Deposits 863 693
Other 126 126
Total other non-current financial assets 5,919 5,102
Advances related to CRO contracts 7,418 7,945
Receivable from Citibank 1,226
Deposits 136
Total other current financial assets 7,554 9,171

Advances related to CRO contracts

These advances granted in 2022 for clinical studies are to be recovered at the end of the studies after final reconciliation with pass-

through costs, which are being invoiced and paid as studies are carried out. These long-term advances were measured at fair value on

initial recognition, using discount rates ranging from 0.19% to 7.16%, and are subsequently measured at amortized cost. The recovery

dates of the first two advances are scheduled in the first half of 2026.

During the first half of 2023, additional advances related to CRO contracts amounting to €1,620 thousand were made (undiscounted

amount). These long-term advances were measured at fair value on initial recognition, using discount rates ranging from 7.09% to

7.59%, and are subsequently measured at amortized cost.

At inception, a prepaid expenses asset was recognized for the difference between the advances’ nominal value and fair value, and

spread over the term of the advances, at the rate of recognition of the related R&D expenses (see Note 10).

In March 2024, a change order was signed with the CRO, extending the scope (addition of maintenance studies) and end date of one of

the studies to 2029, thus postponing the recovery date of the corresponding advance of €5,538 thousand from June 2026 to June 2029.

The Group considered that this asset modification met the criteria for derecognition, and recognized a new financial asset at fair value

on that date, using a discount rate of 6.83%. Since the Group considers that these advances are made in exchange for a discount on

future services to be received from the CROs, a prepaid expense asset was also recognized for the difference between the

derecognized asset carrying value and new asset fair value, and spread over the term of the advance (equal to the period of service) in

a similar manner.

The credit risk related to these advances is deemed insignificant due to the CROs' credit ratings.

Receivable from Citibank

As part of the depositary agreement between Citibank and the Group, the latter is entitled to receive a portion of the issuance,

cancellation and depositary service fees collected from ADS holders by Citibank, who is acting as the Group's exclusive depositary for

its publicly listed ADSs (see Note 18).

Deposits

F-20

Deposits include the Paris and Boston offices lease contracts, the ATM Program, as well as other security deposits.

Note 10. Other receivables and assets

Other receivables and assets break down as follows:

(amounts in thousands of euros) AS OF<br><br>DECEMBER 31,<br><br>2024 AS OF<br><br>SEPTEMBER<br><br>30, 2025
OTHER RECEIVABLES AND ASSETS
Prepaid expenses - non current 948 717
Total non-current other receivables and assets 948 717
Research tax credit ("CIR") 5,774 2,791
VAT receivables 9,841 10,270
Prepaid expenses 3,233 1,988
Employee-related receivables 5,362
Credit notes 48 11
Total current other receivables and assets 18,896 20,421
Other receivables and assets 19,843 21,137

Research tax credit (“CIR”)

The CIR is recognized as Other Operating Income in the year to which the eligible research expense relates. The Group received the

payment for the CIR for the 2024 tax year of €5,640 thousand in June 2025. The additional CIR of €2,791 thousand recorded over the

nine-month period ended September 30, 2025 relates to research expenses incurred during the period.

Employee-related receivables

In connection with the vesting of AGAs granted to its employees in the U.S. (analogous to restricted stock units), the Group settles its

U.S. employee tax obligations on their behalf through a "sell-to-cover" mechanism. A portion of the vested shares is sold on behalf of

the employees to fund the withholding taxes, with employees receiving the remaining shares net of the amounts sold.

As of September 30, 2025, the Group had settled such U.S. employee tax obligations of €5,362 thousand in advance of receiving the

proceeds from the sale of the corresponding shares. The sell-to-cover transactions were completed in October 2025 and the related

receivable was settled.

Prepaid expenses

Prepaid expenses as of September 30, 2025 include prepaid expenses related to CRO contracts for an amount of €1,171 thousand (see

Note 9) and other expenses from various suppliers amounting to €1,534 thousand.

F-21

Note 11. Cash and cash equivalents

Cash and cash equivalents break down as follows:

(amounts in thousands of euros) AS OF<br><br>DECEMBER 31,<br><br>2024 AS OF<br><br>SEPTEMBER 30,<br><br>2025
CASH AND CASH EQUIVALENTS
Cash equivalents 87,265 573,318
Cash 56,956 16,385
Cash and cash equivalents 144,221 589,703

Cash equivalents mainly include term deposits with short-term maturities and highly liquid investments in mutual funds as of

December 31, 2024 and September 30, 2025. As of September 30, 2025, cash equivalents include the invested proceeds from the

Offering.

As of December 31, 2024 and September 30, 2025, in addition to the Group’s bank accounts, cash includes notice accounts amounting

to €44,239 thousand and €15,169 thousand respectively. These funds are available on demand within 24 hours and without penalty.

As of December 31, 2024 and September 30, 2025, the impact of the revaluation of cash and cash equivalents held in U.S. dollars into

the Company's functional currency is a net financial gain of €2,035 thousand and a net financial loss of €8,297 thousand, respectively.

F-22

Note 12. Financial assets and liabilities

The following table shows the carrying amounts and fair value of financial assets and financial liabilities, including their

levels in the fair value hierarchy.

Tax and employee-related payables are non-financial liabilities and are therefore excluded from the tables below. They are

presented in Note 17.2.

AS OF<br><br>DECEMBER 31,<br><br>2024
(amounts in thousands of euros) AMOUNT<br><br>RECOGNIZED<br><br>IN THE<br><br>STATEMENT<br><br>OF FINANCIAL<br><br>POSITION FAIR VALUE ASSETS/<br><br>LIABILITIES AT<br><br>FAIR VALUE<br><br>THROUGH<br><br>PROFIT AND<br><br>LOSS ASSETS AT<br><br>AMORTIZED<br><br>COST LIABILITIES<br><br>AT AMORTIZED<br><br>COST
Other financial assets (2) 13,473 12,690 12,690
Other receivables and assets (2) 19,843 19,843 19,843
Cash and cash equivalents (1) 144,221 144,221 144,221
Total financial assets 177,537 176,754 176,754
Financial liabilities—non-current portion (4, Note 15) 69,069 73,497 3,620 69,877
Financial liabilities—current portion (3, Note 15) 44,935 44,935 21,183 23,752
Trade payables and other current liabilities (3) 43,824 43,824 43,824
Total financial liabilities 157,828 162,256 24,803 137,453 AS OF<br><br>SEPTEMBER 30,<br><br>2025
--- --- --- --- --- --- ---
(amounts in thousands of euros) AMOUNT<br><br>RECOGNIZED<br><br>IN THE<br><br>STATEMENT<br><br>OF FINANCIAL<br><br>POSITION FAIR VALUE ASSETS/<br><br>LIABILITIES AT<br><br>FAIR VALUE<br><br>THROUGH<br><br>PROFIT AND<br><br>LOSS ASSETS AT<br><br>AMORTIZED<br><br>COST LIABILITIES<br><br>AT AMORTIZED<br><br>COST
Other financial assets (2) 14,273 13,904 13,904
Other receivables and assets (2) 21,137 21,137 21,137
Cash and cash equivalents (1) 589,703 589,703 441,318 148,385
Total financial assets 625,114 624,744 441,318 183,426
Financial liabilities—non-current portion (4, Note 15) 44,588 (29,400) 109,751 109,751
Financial liabilities—current portion (3, Note 15) 29,400 29,400 29,400
Trade payables and other current liabilities (3) 30,019 30,019 30,019
Total financial liabilities 104,007 169,170 169,170

(1)    The fair value of cash and cash equivalents is determined based on Level 1 fair value measurement and corresponds to the

market value of the assets.

(2)    The carrying amount of financial assets measured at amortized cost is deemed to be a reasonable estimate of fair value, except

for the long-term advances made to CROs, whose fair value is determined based on Level 3 fair value measurement and is estimated

based on future cash-flows discounted at market rates, using credit spreads ranging from 104 bp to 218 bp as of December 31, 2024

and 36 bp to 188 bp as of September 30, 2025. As of December 31, 2024 and September 30, 2025, an increase in the credit spread by

+100 bp would result in a decrease in the advances fair value by €236 thousand and €243 thousand respectively.

(3)    The carrying amount of short-term financial liabilities measured at amortized cost was deemed to be a reasonable estimate of

fair value.

F-23

(4)    The fair value of the royalty certificates, Heights convertible notes, Kreos / Claret BSA and Minimal Return Indemnifications is

based on Level 3 fair value measurement and is estimated based on models and assumptions detailed in Note 15. The fair value of

other long-term financial liabilities is determined based on Level 3 fair value measurement and is estimated based on future cash-flows

discounted at market rates, using the following assumptions:

•For the debt components of the Kreos / Claret OCABSA (tranche A) and tranches B and C of the Kreos / Claret straight bond

loans, a credit spread of 750 bp as of December 31, 2024 and 850 bp as of September 30, 2025.

As of December 31, 2024 and September 30, 2025, an increase in the credit spread by +100 bp would result in a decrease in

the Kreos / Claret tranche A (OCABSA), tranches B and C debt components fair value by respectively €538 thousand and

€344 thousand, respectively (the OCABSA held by Kreos being fully converted and no longer oustanding as of September

30, 2025).

•For the PGE loan, a credit spread of 900 bp as of December 31, 2024. As of December 31, 2024 an increase in the credit

spread by +100 bp would result in a decrease in the PGE loan fair value by €39 thousand. The PGE being a short-term

liability as of September 30, 2025, its carrying amount measured at amortized cost is deemed to be a reasonable estimate of

its fair value on that date.

Note 13. Shareholders’ equity

Note 13.1. Share capital issued

The Company manages its capital to ensure that it will be able to continue as a going concern while maximizing the return to

shareholders through the optimization of the debt and equity balance.

As of September 30, 2025, the Company’s share capital amounted to €778 thousand divided into 77,830,067 ordinary shares issued

with a par value of €0.01 each, fully paid up, after taking into account the various capital increases that took place since inception.

Share capital does not include founders’ share subscription warrants (“bons de souscription de parts de créateur d’entreprise” or

“BCE”), share subscription warrants (“Bons de souscription d’actions,” or “BSA”) and free shares (“Attributions gratuites d’actions,”

or “AGA”) that have been granted to certain investors or natural persons, both employees and non-employees of the Group, but not yet

exercised.

The Company held none of its own shares as of December 31, 2024 and September 30, 2025.

The number of outstanding ordinary shares was 63,347,837 and 77,830,067 as of December 31, 2024 and September 30, 2025,

respectively.

Note 13.2. Change in share capital

The increase in the share capital for the nine months ended September 30, 2025 relates to (i) the public Offering completed in July

2025, (ii) the conversion of the Heights notes (see Note 15.2), (iii) the exercise of the Kreos / Claret BSA, (iv) the conversion of the

Kreos OCABSA (see Note 15.1), (v) the vesting of 546,905 AGAs and (vi) the exercise of 24,246 BCEs (see Note 14), resulting in the

issuance of respectively 11,679,400, 920,377, 525,913, 785,389, 546,905 and 24,246 ordinary shares (i.e. 14,482,230 in the aggregate)

with a par value of €0.01 per share.

Distribution of dividends

The Group did not distribute any dividends during any of the periods presented, does not have any present plan to pay any cash

dividends on its equity securities in the foreseeable future and currently intends to retain all available funds and any future earnings to

operate and expand its business.

F-24

Note 14. Share-based payments

The Group has granted BCEs, BSAs and AGAs. These plans qualify as “equity settled” under IFRS 2. The Group does not have any

obligation to purchase these instruments in the event of departure or if a specific event does not occur.

BCEs

The following tables summarize the data relating to BCEs:

TYPE NUMBER<br><br>OF BCEs<br><br>ISSUED NUMBER<br><br>OF BCE<br><br>OUTSTAND<br><br>ING AS OF<br><br>JANUARY<br><br>1, 2025 NUMBER<br><br>OF ISSUED<br><br>BCEs NUMBER<br><br>OF LAPSED<br><br>BCEs NUMBER<br><br>OF<br><br>EXERCISE<br><br>D BCEs NUMBER<br><br>OF BCEs<br><br>OUTSTAND<br><br>ING NUMBER<br><br>OF BCEs<br><br>EXERCISA<br><br>BLE MAXIMUM<br><br>NUMBER OF<br><br>SHARES TO<br><br>BE ISSUED IF<br><br>ALL<br><br>CONDITIONS<br><br>ARE MET
FOR THE NINE MONTHS ENDED<br><br>SEPTEMBER 30, 2025 AS OF<br><br>SEPTEMBER 30, 2025
BCE-2016-1 84,000 18,796 (13,796) 5,000 5,000 5,000
BCE-2017-1 67,374 67,000 67,000 41,735 67,000
BCE-2017-2 150,000 112,500 112,500 112,500 112,500
BCE-2017-4 67,374 67,373 67,373 33,686 67,373
BCE-2017-5 67,374 33,687 33,687 16,843 33,687
BCE-2018-1 22,000 11,980 (8,450) 3,530 3,530 3,530
BCE-2018-4 16,843 16,843 16,843 8,422 16,843
BCE-2018-5 22,000 2,000 (2,000)
Total BCEs 496,965 330,179 (24,246) 305,933 221,716 305,933

F-25

BSAs

The following tables summarize the data relating to BSAs:

GRANT DA<br><br>TE TYPE Total<br><br>NUMBER<br><br>OF BSAs<br><br>ISSUED NUMBER<br><br>OF BCAs<br><br>OUTSTAND<br><br>ING AS OF<br><br>JANUARY<br><br>1, 2025 NUMBER<br><br>OF ISSUED<br><br>BSAs NUMBER<br><br>OF LAPSED<br><br>BSAs NUMBER<br><br>OF<br><br>EXERCISE<br><br>D  BSAs NUMBER<br><br>OF BSAs<br><br>OUTSTAND<br><br>ING NUMBER<br><br>OF BSAs<br><br>EXERCISA<br><br>BLE MAXIMUM<br><br>NUMBER OF<br><br>SHARES TO<br><br>BE ISSUED IF<br><br>ALL<br><br>CONDITIONS<br><br>ARE MET
FOR THE NINE MONTHS ENDED<br><br>SEPTEMBER 30, 2025 AS OF<br><br>SEPTEMBER 30, 2025
2015-12-04 BSA-2015-11 96,924 96,924 96,924 96,924 96,924
2015-12-04 BSA-2015-12 82,000 16,400 16,400 16,400 16,400
2017-09-18 BSA-2017-1 16,400 16,400 16,400 16,400 16,400
2018-01-22 BSA-2018-1 49,200 16,400 16,400 16,400 16,400
2024-04-04 BSA-2024-1 58,365 58,365 58,365 58,365
2024-04-04 BSA-2024-2 19,455 19,455 19,455 19,455
2025-01-13 BSA-2025-1 100,000 100,000 100,000 100,000
2025-01-13 BSA-2025-2 25,000 25,000 25,000 25,000
2025-04-22 BSA-2025-3 39,370 39,370 39,370 39,370 39,370
Total BSAs 486,714 223,944 164,370 0 388,314 146,124 388,314

BSAs granted in January and April 2025

In January 2025, the Group granted its independent Board members, as well as one of its Board Observers and Advisor, the right to

subscribe up to 125,000 BSAs in the aggregate, the vesting of which (if subscribed) is subject to a service condition of four years, by

tranches of 25% each, vested on January 1 of each year. Additionally, the BSAs are subject to a vesting acceleration condition in case

of a tender offer on the securities issued by the Group and resulting in a change of control of the Group. All of the granted BSAs were

subscribed by the beneficiaries in February 2025.

In April 2025, the Group granted to one of its Board members the right to subscribe up to 39,370 BSAs, the vesting of which is subject

to a service condition of four years, by tranches of 25% each, vested on May 1 of each year. The BSAs were subscribed in May 2025.

The fair value of the BSAs was determined at grant date using the Black Scholes model, with the following assumptions:

TYPE FAIR VALUE<br><br>OF THE<br><br>UNDERLYING<br><br>SHARE FAIR VALUE<br><br>OF THE BSA NUMBER OF<br><br>BSAs SUBSCRIPTI<br><br>ON PRICE STRIKE<br><br>PRICE PER<br><br>SHARE RISK FREE<br><br>RATE EXPECTED<br><br>MATURITY VOLATILITY
BSA-2025-1 €6.13 [€3.5-€3.9] 100,000 €2.00 €6.63 4.65% [5.5-7 years] 60.88%
BSA-2025-2 €6.13 [€3.5-€3.9] 25,000 €2.00 €6.63 4.65% [5.5-7 years] 60.88%
BSA-2025-3 €6.48 [€3.7-€4.1] 39,370 €1.27 €6.41 3.92% [5.5-7 years] 60.69%

AGAs

The following tables summarize the data relating to AGAs as well as the assumptions used for the measurement thereof in

accordance with IFRS 2—Share-based Payment:

F-26

GRANT DATE TYPE Total NUMBER<br><br>OF AGAs<br><br>ISSUED NUMBER OF<br><br>AGAs<br><br>OUTSTANDING<br><br>AS OF<br><br>JANUARY 1,<br><br>2025 NUMBER OF<br><br>ISSUED AGAs NUMBER OF<br><br>LAPSED AGAs NUMBER OF<br><br>VESTED AGAs NUMBER OF<br><br>AGAs<br><br>OUTSTANDING
FOR THE NINE MONTHS ENDED SEPTEMBER 30,<br><br>2025 AS OF<br><br>SEPTEMBER 30,<br><br>2025
2023-07-11 AGA-2023-1 1,382,796 780,040 (177,280) 602,760
2023-07-11 AGA-2023-2 100,000 75,000 (75,000)
2023-09-28 AGA-2023-3 731,500 485,875 (15,500) (251,125) 219,250
2023-09-28 AGA-2023-4 254,250 213,250 (1,250) (108,500) 103,500
2023-12-01 AGA-2023-5 132,750 81,250 (26,000) 55,250
2024-02-01 AGA-2024-1 1,549,125 1,355,625 (30,125) 1,325,500
2024-03-28 AGA-2024-2 22,500 22,500 22,500
2024-05-23 AGA-2024-3 38,500 38,500 (7,500) 31,000
2024-07-11 AGA-2024-4 93,000 93,000 93,000
2024-07-11 AGA-2024-5 25,000 25,000 25,000
2024-07-11 AGA-2024-6 20,000 20,000 (10,000) 10,000
2024-09-05 AGA-2024-7 198,000 198,000 198,000
2025-02-06 AGA-2025-1 4,319,500 4,319,500 (5,500) 4,314,000
2025-02-06 AGA-2025-2 123,102 123,102 123,102
2025-02-06 AGA-2025-3 17,625 17,625 17,625
2025-02-06 AGA-2025-4 30,500 30,500 30,500
2025-03-20 AGA-2025-5 50,000 50,000 50,000
2025-05-30 AGA-2025-6 25,000 25,000 25,000
2025-08-01 AGA-2025-7 1,711,000 1,711,000 1,711,000
Total AGAs 0 10,824,148 3,388,040 6,276,727 (160,875) (546,905) 8,956,987 TYPE FAIR VALUE OF<br><br>THE<br><br>UNDERLYING<br><br>SHARE FAIR VALUE OF<br><br>THE AGA MATURITY VOLATILITY RISK FREE RATE
--- --- --- --- --- ---
AGA-2025-1 €5.82 €5.82 N/A N/A N/A
AGA-2025-2 €5.82 €5.82 N/A N/A N/A
AGA-2025-3 €5.82 €5.82 N/A N/A N/A
AGA-2025-4 €5.82 €5.82 N/A N/A N/A
AGA-2025-5 €6.17 €6.17 N/A N/A N/A
AGA-2025-6 €5.17 €5.17 N/A N/A N/A
AGA-2025-7 €61.20 €61.20 N/A N/A N/A

AGAs granted in February, March, May and August 2025

From February to August 2025, certain of the Group’s officers and employees were allocated 4,319,500 AGAs (AGA plan 2025-1),

123,102 AGAs (AGA plan 2025-2), 17,625 AGAs (AGA plans 2025-3), 30,500 AGAs (AGA plan 2025-4), 25,000 AGAs (AGA plan

2025-6) and 1,711,000 AGAs (AGA plan 2025-7) in the aggregate, the vesting of which is subject to certain conditions:

F-27

•Subject to remaining employed with the Group, each such officer or employee’s AGAs will be vested as follows: (i) 50% at

the end of a two-year period from the allocation date, (ii) 25% at the end of a three-year period from the allocation date and

(iii) 25% at the end of a four-year period from the allocation date (service condition).

•By exception to the above, the vesting of almost half of the 4,319,500 2025-1 AGAs is subject to the occurrence of a tender

offer on the securities issued by the Group and resulting in a change of control of the Group before a certain date, and the

123,102 2025-2 AGAs will vest entirely at the end of a two-year period from the allocation date.

•Additionally, all the remaining 2025-1 AGAs as well as the 2025-2, 2025-3 and 2025-4 AGAs are subject to a vesting

acceleration condition in case of a tender offer on the securities issued by the Group and resulting in a change of control of

the Group.

In March 2025, a Group employee was allocated 50,000 AGAs (AGA plan 2025-5), the vesting of which is subject to the achievement

of certain milestones related to clinical studies and market authorization of ABX464 in UC and CD. These AGAs are also subject to a

vesting acceleration condition in case of a tender offer on the securities issued by the Group and resulting in a change of control of the

Group.

Breakdown of the compensation expenses accounted for the three- and nine-month periods ended September 30,

2024 and 2025:

TYPE<br><br>(in thousands of euros) FOR THE<br><br>THREE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2024 FOR THE<br><br>THREE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2025 FOR THE NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2024 FOR THE NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2025
BCEs (56) (84)
BSAs (130) (142) (199) (213)
AGAs (9,914) (16,023) (15,484) (22,284)
Social taxes related to AGAs (441) (30,251) (619) (30,918)
Total (10,541) (46,416) (16,386) (53,415)

The significant amount of social taxes related to AGAs (and related provisions) for the nine months ended September 30, 2025 is

attributable to the increase in the price of the underlying shares over the period.

Provisions for social taxes related to AGAs are classified within the Current Provisions and Non-current Provisions line items in the

balance sheet, which amount to €532 thousand and €819 thousand, respectively, as of December 31, 2024 and €11,412 thousand and

€16,622 thousand, respectively, as of September 30, 2025.

F-28

Note 15. Financial liabilities

Financial liabilities break down as follows:

(amounts in thousands of euros)
FINANCIAL LIABILITIES AS OF<br><br>DECEMBER 31,<br><br>2024 AS OF<br><br>SEPTEMBER 30,<br><br>2025
Kreos & Claret bond loans 26,373 11,779
Lease liabilities 1,431 611
PGE 1,252
Borrowings 29,056 12,390
Kreos & Claret convertible notes (OCABSA) 23,370 4,099
Convertible loan notes 23,370 4,099
Kreos & Claret minimal return indemnifications 3,620
Derivative instruments 3,620
Royalty certificates 13,023 28,099
Other financial liabilities 13,023 28,099
Total non-current financial liabilities 69,069 44,588
Kreos & Claret bond loans 20,028 23,040
Lease liabilities 932 938
PGE 1,235 1,252
Borrowings 22,195 25,230
Heights convertible notes 21,574
Kreos & Claret convertible notes (OCABSA) 4,170
Convertible loan notes 21,574 4,170
Kreos & Claret BSA 1,166
Derivative instruments 1,166
Total current financial liabilities 44,935 29,400
Total financial liabilities 114,004 73,988

Note 15.1. Structured debt financing with Kreos & Claret subscribed in August 2023 – “Kreos / Claret Financing”

The Kreos / Claret Financing consists of three tranches of €25,000 thousand each in aggregate principal amount (the convertible

OCABSA and the second and third tranches of non-convertible bonds, respectively the "tranches A, B and C") as well as a Minimal

Return Indemnification ("MRI") to the benefit of the bondholders.

In addition to the Kreos / Claret OCABSA, the Group has issued share warrants (the “tranche A-B BSA” and “tranche C BSA”),

giving Kreos and Claret the right to subscribe to up to 214,198 and 405,832 ordinary shares respectively.

The OCABSA are compound instruments, split between (i) a debt component (then measured at amortized cost) and (ii) an equity

component corresponding to the conversion option and the attached OCABSA warrants.

The OCABSA warrants are considered as an embedded component of the bonds rather than a separate stand-alone financial

instrument.

The Kreos / Claret second and third tranches are hybrid instruments, split between (i) debt host contracts accounted for at amortized

cost and (ii) bifurcated embedded derivatives accounted for at fair value through profit and loss, corresponding to the Minimal Return

Indemnifications and the prepayment options (the fair value of the prepayment options being deemed insignificant at issuance and as

of December 31, 2024 and September 30, 2025).

F-29

As the A-B and C warrants (the "Kreos / Claret BSA") are contractually transferable separately from the bonds and are redeemable in

a variable number of ordinary shares of the Group, they are classified as standalone derivative financial liabilities.

The detailed terms and conditions and the accounting treatment of these instruments are presented in Note 15.1 to the annual

consolidated financial statements of the Group as of December 31, 2024 accompanying the Group’s Annual Report.

On August 6, 2025, Kreos Capital VII(UK) Limited converted the Tranche A portion of the Kreos / Claret Financing (the Kreos /

Claret OCABSA), resulting in the issuance of 785,389 ordinary shares and an increase in equity by €16,058 thousand.

In addition, on the same date Kreos Capital VII Aggregator SCSp opted for the cashless exercise of its share warrants (the tranche A-B

BSA and tranche C BSA), implemented through the repurchase by the Company of 94,117 tranche A-B and C BSA and the issuance

of 319,251 ordinary shares of the Company. At this date, the fair value of exercised warrants of €15,143 thousand was reclassified

from derivative financial liabilities to equity. As of this date, due to the put option being exercised by the holders, the fair value of the

BSAs is deemed equal to their intrinsic value, which is equal to the difference between the share price on August 6, 2025 and their

exercise price.

On August 28, 2025, Claret European Growth Capital Fund III SCSp, exercised its share warrants (the tranche A-B BSA and tranche

C BSA) for 206,662 shares of the Company. At this date, the fair value of exercised warrants of €11,531 thousand was reclassified

from derivative financial liabilities to equity.

In the context of the Minimal Return Indemnification, the Minimum Cash Return amount was defined as follows:

(i) with respect to tranche A and tranche B, 1.4 times the amount of the cumulated principal drawn under the relevant

instrument, and;

(ii) with respect to tranche C, 1.3 times the amount of the cumulated principal drawn under the relevant instrument.

In the event the amount of the cash generated by the tranche A (the Kreos / Claret OCABSA), tranche B or tranche C bond loans,

including principal and interest payments, transaction fees, and the end-of-loan exit fees, (the “Actual Return” calculated as at the

earlier of (i) March 31, 2027, or (ii) the date of any prepayment or acceleration of the tranche B and C bond loans or more generally

such earlier date as the same shall become repayable ("the Redemption Date")), is lower than the Minimum Cash Return, the Group

shall indemnify the bondholders for the difference between the Minimum Cash Return and the Actual Return (the “Minimal Return

Indemnification").

In July 2025, as a result of (i) the repayments of principal and interests made until that date, (ii) the exercise of the Tranche A-B and C

BSA and (iii) the conversion of the Kreos OCABSA, the cash generated thereby met the Minimum Cash Return due to the Kreos /

Claret bondholders. Consequently, as no further payment could be due by the Group in relation to the Kreos / Claret Minimal Return

Indemnification, the MRI derivatives amounting to €3,620 thousand were derecognized on that date.

On November 25, 2025, Claret European Growth Capital Fund III SCSp converted its portion of the Tranche A portion of the Kreos /

Claret Financing (the Claret OCABSA), resulting in the issuance of 392,695 ordinary shares of the Group. Following this conversion,

the Group no longer holds any debt related to the Tranche A of the Kreos Claret Financing.

On November 28, 2025, the Group notified the bondholders of its intention to prepay in full the outstanding balances of Tranches B

and C of the Kreos / Claret Financing. The transaction is expected to be completed before December 31, 2025. Following this

redemption, the Group would no longer hold any debt related to the entire Kreos / Claret Financing.

Measurement of the Kreos / Claret second and third tranches hybrid instruments

At inception, the net cash proceeds reflect the tranches' initial fair values. The fair values of the Minimal Return Indemnifications were

deducted from the initial carrying values of the debt components of each tranche, which were subsequently measured at amortized cost

using the effective interest rate ("EIR") method.

F-30

The fair values of the Minimal Return Indemnifications were measured using the following assumptions:

Tranche B Minimal Return Indemnification - March 2024 AS OF DECEMBER 31, 2024
Minimal return 1.40x
Discount rate 7.50%
Probability-weighted present value of shortfall payment (in<br><br>thousands of €) 2,635 (Final redemption)<br><br>136 (Tender offer)
Probability-weighted fair value of tranche A-B warrants with MRI<br><br>(in thousands of €) 104 (Final redemption)
Probability-weighted fair value of tranche A-B warrants without<br><br>MRI (in thousands of €) 241 (Final redemption)
Total fair value of MRI (in thousands of €) 2,499 (Final redemption, i.e. a+b-c)<br><br>136 (Tender offer)
Fair value of Tranche B MRI (in thousands of €) 2,636 Tranche C Minimal Return Indemnification - June 2024 AS OF DECEMBER 31, 2024
--- ---
Minimal return 1.30x
Discount rate 7.50%
(a) Probability-weighted present value of shortfall payment (in<br><br>thousands of €) 1,160 (Final redemption)<br><br>43 (Tender offer)
(b) Probability-weighted fair value of tranche A-B warrants with<br><br>MRI (in thousands of €) 684 (Final redemption)
(c) Probability-weighted fair value of tranche A-B warrants without<br><br>MRI (in thousands of €) 903 (Final redemption)
Total fair value of MRI (in thousands of €) 941 (Final redemption, i.e. a+b-c)<br><br>43 (Tender offer)
Fair value of Tranche C MRI (in thousands of €) 984

For the purpose of measuring the fair value of the MRI (shortfall payment), the fair value of the tranche A-B and C BSA was

measured with a Black Scholes model under the Final redemption scenario and with a Monte Carlo model under the Tender offer

scenario.

As of December 31, 2024, using the same assumption with an increase of +1% volatility, €+1 share price, +1% risk-free rate, +10% in

the probability of achieving the Final redemption scenario and +1% discount rate would result in changes of the MRI B and C fair

value by respectively €(1) thousand, €(3) thousand, €(3) thousand, €+3 thousand and €(82) thousand.

Measurement of the Kreos / Claret tranche A-B-C BSA

The Kreos / Claret tranche A-B and tranche C BSA are measured at fair value using a Black-Scholes valuation model. The model

considers two probability-weighted scenarios, i.e. (i) the 7-year expiry of the BSA and (ii) an earlier exercise upon a tender offer. The

main data and assumptions are the following:

F-31

Kreos/Claret Tranche A-B BSA - August 2023 AS OF DECEMBER 31, 2024
Number of outstanding BSA 214,198
Exercise price per share €18.67
Ordinary share price €6.76
Exercise date 19/08/2030 (expiry)<br><br>18/02/2027 (tender offer)
7-year expiry scenario probability 95%
Volatility 44.3% (expiry)<br><br>44.3% (tender offer)
Dividend 0
Risk-free rate 2.9% (expiry)<br><br>2.9% (tender offer)
Fair value of issued Kreos/Claret Tranche A-B BSA 243 Kreos/Claret Tranche C BSA - November 2023 AS OF DECEMBER 31, 2024
--- ---
Number of outstanding BSA 405,832
of which, number of conditional BSA 0
Exercise price per share €9.86
Ordinary share price €6.67
Exercise date 01/11/2030 (expiry)<br><br>18/02/2027 (tender offer)
7-year expiry scenario probability 95%
Probability of Drawdown of Tranche C credit facility Drawn on June 21, 2024
Volatility 44.3% (expiry)<br><br>44.3% (tender offer)
Dividend 0
Risk-free rate 2.9% (expiry)<br><br>2.9% (tender offer)
Fair value of issued Kreos/Claret Tranche A-B BSA 923

As of December 31, 2024, using the same assumption with an increase of +1% volatility, €+1 share price, +1% risk-free rate and

+10% in the probability of achieving the 7 years expiry scenario would result in an increase of Kreos / Claret A-B and C BSA fair

value by respectively €37 thousand, €350 thousand, €61 thousand and €75 thousand.

Note 15.2.  Heights convertible notes

The Heights convertible notes consists of (i) a host debt instrument and (ii) conversion and settlement options representing embedded

derivatives. The whole instrument is measured at fair value through profit or loss ("FVTPL") at each reporting date.

At inception, the Heights convertible notes' fair value differed from the issuance proceeds by €2,359 thousand.

Since the fair value measurement of the instrument is evidenced by a valuation technique that does not only use data from observable

F-32

markets, the carrying amount was adjusted to defer the difference between the fair value measurement and the transaction price, and

the day one gain is therefore recognized in financial income on a straight-line basis over the term of the instrument.

In application of the Amendments to IAS 1 Presentation of Financial Statements – Classification of Liabilities as Current or Non-

current, and Non-current Liabilities with Covenants, the Heights convertible notes are classified as current financial liabilities.

The fair value of the Heights convertible notes (including the embedded features) has been measured with a Monte Carlo model,

considering two probability-weighted scenarios: (i) a Put Event or Default/Dissolution scenario and (ii) a voluntary conversion at

maturity scenario. The main data and assumptions are the following:

Heights convertible notes - August 2023 AS OF DECEMBER 31, 2024
Original principal amount (in thousands of €) 35,000
Interest rate 6%
Conversion price per share €23.77
Ordinary share price €6.76
Maturity date 24/08/2025 (put event)<br><br>24/08/2027 (HTM/voluntary conversion)
Held to maturity scenario probability 75%
Initial price limit €14.43
Early redemption amount (put event) 120.00%
Volatility 50%
Credit spread 25%
Risk-free rate 2.9%
Fair value of Heights convertible notes (in<br><br>thousands of €) 20,017

As of December 31, 2024, using the same assumptions with an increase of +1% volatility, €+1 share price, +1% risk-free rate and

+10% probability of achieving the held to maturity scenario would result in a change in the Heights convertible notes fair value by

respectively €+2 thousand, €+39 thousand, €(219) thousand and €(631) thousand.

On July 23 and July 30, 2025, the noteholders requested the conversion of respectively 150 and 200 convertible notes (corresponding

to the entirety of the outstanding principal amount of approximately €21.9 million) into 920,377 new ordinary shares of the Group at a

conversion price of €23.7674 per ordinary share (see Note 3.2 "Conversion of the Heights convertible notes – July-August 2025").

At these dates, the fair value of the converted notes of €53,921 thousand was reclassified from financial liabilities to equity. On the

conversion dates, due to the put option being exercised by the holders, the fair values of the Heights notes were deemed equal to the

market prices of the issued shares.

As a result of the derecognition of the Heights notes, the outstanding day-one gain was entirely amortized, resulting in a financial

income of €1,262 thousand.

F-33

Note 15.3. State guaranteed loan – “PGE”

The payment of the last installment of the State-guaranteed loan (Prêt garanti par l'Etat, or "PGE") is scheduled in June 2026.

Note 15.4. Lease liabilities

The variations in lease liabilities are set forth below:

AS OF<br><br>DECEMBER 31, 2023 540
(+) Increase 2,051
(-) Decrease (406)
AS OF<br><br>SEPTEMBER 30, 2024 2,185
AS OF<br><br>DECEMBER 31, 2024 2,363
(+) Increase
(-) Decrease (814)
AS OF<br><br>SEPTEMBER 30, 2025 1,549

Lease liabilities mainly relate to the Group’s former headquarters in Paris (as of December 31, 2023), the Boston office entered into in

November 2023, the Montpellier offices entered into in April 2024, the new Paris headquarters entered into in May 2024 and to a

lesser extent to vehicles, parking lots and printers (Note 8).

As of December 31, 2024 and September 30, 2025, the lease liabilities of the Paris headquarters and Boston offices represented 93%

and 96% of the total lease liability, respectively.

Lease expenses related to contracts for which a lease liability and right of use asset is recognized under IFRS 16 were €412 thousand

and €637 thousand for the nine-month periods ended September 30, 2024 and 2025, respectively. They were recognized for (i)

€591 thousand and €568 thousand as Depreciation expenses and (ii) €43 thousand and €51 thousand as Interest expenses, for the nine-

month periods ended September 30, 2024 and 2025, respectively.

Lease expenses related to short-term lease contracts and low value assets that are not included in the valuation of the lease liability

amount to €251 thousand, and €172 thousand for the nine-month periods ended September 30, 2024 and 2025, respectively.

F-34

Note 15.5. Royalty certificates

The royalty certificates are measured at amortized cost using the EIR method.

During the third quarter of 2025, the Group revised the probability of success (“POS”) of the obefazimod clinical trials to take into

account the Phase 3 results announced in July 2025 and reassessed its estimate of future royalty cash flows accordingly. This change

in estimate resulted in a remeasurement of the certificates’ amortized costs, using the original EIR of 34% calculated at the date of

issuance, which led to an increase by €11,318 thousand of the royalty certificates liability. The expense was recorded within the

financial expenses in the Statements of Income (Loss).

As of September 30, 2025, using the same future royalty cash flows assumptions with an increase of +5 points of POS and +5% of

peak penetration (best case scenario) would result in an increase in the royalty certificates carrying value by respectively €

+1,439 thousand and €+2,436 thousand. Using the same assumptions with a decrease of (5)% points of POS and (5)% of peak

penetration (worst case scenario) would result in a decrease in the royalty certificates carrying value by respectively €(1,591) thousand

and €(3,851) thousand.

Fair value

The fair value of the royalty certificates amounts to €7,313 thousand as of December 31, 2024 and €88,094 thousand as of September

30, 2025. The variation is primarily explained by the revised POS, reflecting the results of the Phase 3 trials, and by the decrease in the

discount rate, both reflected by the increase in the Group's share price during the third quarter of 2025 (see Note 3.2 - Publication of

positive Phase 3 results from both ABTECT 8-week induction trials investigating obefazimod, in moderate to severely active UC – July

2025).

The fair value of the royalty certificates is based on the net present value of royalties, which depends on assumptions made by the

Group with regards to the POS of its studies, the commercialization budget of obefazimod (“peak penetration”) and the discount rate.

In addition, as of December 31, 2024, royalty projections have been adjusted to reflect the significant difference between the Group’s

value derived from management projections and the Group’s market capitalization. As of September 30, 2025, following the increase

in the Group's share price and the business plan update, such adjustment was no longer required. Management ensured that the

discount rate of 10.0% used is reasonable based on the specific risk profile of the royalties certificates.

As of December 31, 2024, using the same assumptions with an increase of +5 points of POS, +5% of peak penetration (best case

scenario), +1% discount rate and €+1 share price would result in a change in the royalty certificates fair value by respectively €

+572 thousand, €+1,735 thousand, €(314) thousand and €+1,160 thousand. Using the same assumptions with a decrease of (5)%

points of POS, (5)% of peak penetration (worst case scenario) and (1)% discount rate and €(1) share price would result in a change in

the royalty certificates fair value by respectively €(572) thousand, €(2,527) thousand, €+332 thousand and €(1,160) thousand.

As of September 30, 2025, using the same assumptions with an increase of +5 points of POS, +5% of peak penetration (best case

scenario) and +1% discount rate would result in a change in the royalty certificates fair value by respectively €+5,014 thousand, €

+2,991 thousand and €(4,334) thousand. Using the same assumptions with a decrease of (5)% points of POS, (5)% of peak penetration

(worst case scenario) and (1)% discount rate would result in a change in the royalty certificates fair value by respectively

€(5,014) thousand, €(5,686) thousand, and €4,612 thousand.

F-35

Note 15.6. Change in financial liabilities

Changes in financial liabilities, excluding derivative instruments, are presented below as of September 30, 2024 and 2025:

(Amounts in thousands of euros) Kreos/<br><br>Claret<br><br>convertible<br><br>notes<br><br>(OCABSA) Kreos &<br><br>Claret<br><br>bond<br><br>loans Heights<br><br>convertibl<br><br>e notes PGE Conditional<br><br>advances BPI Lease<br><br>liabilities Royalty<br><br>certificates Total
FINANCIAL LIABILITIES (excluding<br><br>derivatives instruments)
AS OF<br><br>DECEMBER 31, 2023 21,643 29,605 3,678 6,771 540 12,229 74,466
Proceeds 47,444 47,444
Repayments (6,563) (1,250) (1,142) (402) (9,357)
Interest paid (1,688) (2,267) (1,378) (18) (14) (5,364)
Non-cash changes: classification of<br><br>embedded derivatives as separate<br><br>derivative financial instruments (3,204) (3,204)
Non-cash changes: (gain)/loss on<br><br>recognition or derecognition (442) (442)
Non-cash changes: interest expense and<br><br>other 2,956 3,559 1,333 56 7 43 3,023 10,977
Non-cash changes: other fair value<br><br>remeasurement 609 609
Non-cash changes: conversion into shares (4,070) (4,070)
Non-cash changes : subsidies 914 914
Non cash changes: additional leases 2,021 2,021
Non cash changes : Effect of the change in<br><br>foreign currency exchange rates (3) (3)
AS OF<br><br>SEPTEMBER 30, 2024 22,912 45,533 23,164 2,466 2,480 2,185 15,253 113,992
AS OF<br><br>DECEMBER 31, 2024 23,370 46,401 21,574 2,488 2,363 13,023 109,218
Repayments (14,551) (2,188) (1,250) (782) (18,770)
Interest paid (1,688) (2,951) (689) (43) (51) (5,422)
Non-cash changes: (gain)/loss on<br><br>recognition or derecognition (1,557) (1,557)
Non-cash changes: interest expense and<br><br>other 2,644 5,919 778 58 51 3,758 13,209
Non-cash changes: amortized cost<br><br>remeasurement 11,318 11,318
Non-cash changes: other fair value<br><br>remeasurement 36,002 36,002
Non-cash changes: conversion into shares (16,058) (53,921) (69,979)
Non cash changes : Effect of the change in<br><br>foreign currency exchange rates (33) (33)
AS OF<br><br>SEPTEMBER 30, 2025 8,269 34,819 1,252 1,549 28,099 73,988

For the nine-month period ended September 30, 2024, proceeds from the issuance of the Kreos / Claret tranches B and C bond loans

are presented net of transaction costs and deposits (corresponding to the prepayments of half of the last debt installments on issuance

date) included in the debt discount using the EIR method, and amounting to €1,475 thousand and €1,081 thousand respectively. Net

proceeds from non-convertible bond loans of €47,944 thousand disclosed in the Unaudited Condensed Consolidated Statements of

Cash Flows for the nine-month period ended September 30, 2024 do not include transaction fees of €500 thousand related to the

Kreos / Claret tranche A-B warrants classified as prepaid expenses as of December 31, 2023.

Note 15.7. Change in derivative instruments

Changes in derivative instruments are presented below as of September 30, 2024 and 2025:

F-36

(amounts in thousands of euros) Kreos/Claret BSA Kreos/Claret<br><br>Minimal Return<br><br>Indemnifications Total
DERIVATIVE FINANCIAL<br><br>INSTRUMENTS
AS OF<br><br>DECEMBER 31, 2023 2,579 2,579
(+) Issuance 2,158 2,158
(+) Increase in fair value 544 677 1,221
(-) Decrease in fair value (139) (139)
AS OF<br><br>SEPTEMBER 30, 2024 2,984 2,835 5,819
AS OF<br><br>DECEMBER 31, 2024 1,166 3,620 4,786
(+) Increase in fair value 29,935 29,935
(-) Decrease in fair value (3,620) (3,620)
(-) Repurchases (4,427) (4,427)
(-) Exercises (26,674) (26,674)
AS OF<br><br>SEPTEMBER 30, 2025

Details related to these instruments' accounting treatments and terms and conditions are set forth in Notes 15.1 and 15.2 of these

financial statements, as well as in Notes 15.1 and 15.2 to the annual consolidated financial statements of the Group as of December 31,

2024 accompanying the Group’s Annual Report.

Note 15.8. Breakdown of financial liabilities by maturity

The following are the remaining contractual maturities of financial liabilities as of December 31, 2024 and September 30, 2025. The

amounts are gross and undiscounted, and include contractual interest payments.

AS OF<br><br>DECEMBER 31, 2024
CURRENT AND NON-CURRENT<br><br>FINANCIAL LIABILITIES GROSS<br><br>AMOUNT CONTRACTUAL<br><br>CASH FLOWS LESS THAN 1<br><br>YEAR FROM 1 TO 2<br><br>YEARS FROM 2 TO 5<br><br>YEARS LONGER<br><br>THAN 5<br><br>YEARS
(amounts in thousands of euros)
Heights convertible notes 21,574 24,063 8,750 8,750 6,563
Kreos/Claret convertible notes<br><br>(OCABSA) 23,370 30,653 2,250 19,943 8,460
Kreos/Claret bond loans 46,401 58,080 24,016 25,715 8,348
PGE 2,488 2,586 1,293 1,293
Royalty certificates (1) 13,023
Lease liabilities 2,363 2,512 993 996 516 7
Derivative instruments 4,786 4,786 1,166 3,620
Total financial liabilities 114,004 122,680 38,468 56,698 27,507 7

F-37

AS OF<br><br>SEPTEMBER 30, 2025
CURRENT AND NON-CURRENT<br><br>FINANCIAL LIABILITIES GROSS<br><br>AMOUNT CONTRACTUAL<br><br>CASH FLOWS LESS THAN 1<br><br>YEAR FROM 1 TO 2<br><br>YEARS FROM 2 TO 5<br><br>YEARS LONGER<br><br>THAN 5<br><br>YEARS
(amounts in thousands of euros)
Heights convertible notes
Kreos/Claret convertible notes<br><br>(OCABSA) 8,269 9,660 4,684 4,976
Kreos/Claret bond loans 34,819 40,241 25,548 14,693
PGE 1,252 1,268 1,268
Royalty certificates (1) 28,099
Lease liabilities 1,549 1,747 980 672 95
Derivative instruments
Total financial liabilities 73,988 $52,916 32,481 20,341 95

(1) The contractual cash flows above do not include potential future royalty payments related to the royalty certificates, amounting to

2% of the future net sales of obefazimod (worldwide and for all indications). The amount of royalties that may be paid under the

royalty certificates is capped at €172.0 million in the aggregate. Royalty payments are expected to take place before the expiry date of

the certificates, which is 15 years after their issuance date (September 2, 2037), and would be included in the "from 2 to 5 years" and

"longer than 5 years" maturity categories according to management's projections.

Note 16. Retirement benefit obligations

Retirement benefit obligations include the liability for the defined benefit plan, measured based on the provisions stipulated

under the applicable collective agreements, i.e. the French pharmaceutical industry’s collective agreement. This commitment

only applies to employees subject to French law. Employees in the U.S. benefit from defined contribution plans (401(k)).

Note 17. Payables and other current liabilities

Note 17.1. Trade payables and other current liabilities

Trade payables and other current liabilities break down as follows:

(amounts in thousands of euros)
TRADE PAYABLES AND OTHER CURRENT LIABILITIES AS OF<br><br>DECEMBER 31,<br><br>2024 AS OF<br><br>SEPTEMBER 30,<br><br>2025
Trade payables 30,748 14,355
Accrued invoices 13,049 15,663
Other 26
Trade payables and other current liabilities 43,824 30,019

The decrease in Trade payables as of September 30, 2025 compared to December 31, 2024 is mainly attributable to decreased

activity on ABTECT as a result of reaching major milestones in the Phase 3 clinical trials.

F-38

Note 17.2. Tax and employee-related payables

Tax and employee-related payables are presented below:

(amounts in thousands of euros)
TAX AND EMPLOYEE-RELATED PAYABLES AS OF<br><br>DECEMBER 31,<br><br>2024 AS OF<br><br>SEPTEMBER 30,<br><br>2025
Employee-related payables 2,742 3,018
Social security and other 1,783 4,654
Other tax and related payments 184 259
TAX AND EMPLOYEE-RELATED PAYABLES 4,709 7,931

The increase in Social security and other payables relates to social contributions on vested AGAs that have become due.

Note 18. Operating income

Operating income is composed as below:

(amounts in thousands of euros)
OPERATING INCOME FOR THE<br><br>THREE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2024 FOR THE<br><br>THREE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2025 FOR THE NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2024 FOR THE NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2025
Research tax credit ("CIR") 1,332 639 3,997 2,656
Subsidies 20 4,140
Other (27) 1,404 2 1,474
Total operating income 1,324 2,043 8,139 4,130

Research tax credit (“CIR”)

The Group carries out research and development projects. As such, it has benefited from a research tax credit for the nine-month

periods ended September 30, 2024 and 2025 for an amount of €3,997 thousand and €2,656 thousand, respectively.

Subsidies

Subsidies primarily relate to the Bpifrance RNP-VIR and CARENA conditional advances, the repayments of which were partly

waived by Bpifrance in June 2024, for €1,872 thousand and €2,251 thousand respectively (see Note 3.1).

Other

For the nine-month period ended September 30, 2025, the line item "Other" mainly includes issuance, cancellation and depositary

service fees collected from ADS holders by Citibank, who is acting as the Group's exclusive depositary for its publicly listed ADSs.

As part of the depositary agreement between Citibank and the Group, the latter is entitled to receive a portion of the aforementioned

fees collected by Citibank.

The amount recognized for the three-month period ended September 30, 2025 reflects the higher amount of ADS transactions

following the announcement of Phase 3 results and the Group's Offering in July 2025.

Note 19. Operating expenses

F-39

Note 19.1. Sales and marketing

(amounts in thousands of euros)
SALES AND MARKETING FOR THE THREE<br><br>MONTHS ENDED<br><br>SEPTEMBER 30,<br><br>2024 FOR THE THREE<br><br>MONTHS ENDED<br><br>SEPTEMBER 30,<br><br>2025 FOR THE NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER 30,<br><br>2024 FOR THE NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER 30,<br><br>2025
Personnel costs 448 1,256 1,901 2,217
Consulting and professional fees 270 568 2,363 952
Other sales and marketing expenses 135 14 819 203
Sales & Marketing 853 1,838 5,082 3,372

The sales and marketing expenses as of September 30, 2025 consist primarily in consulting costs associated with market research in

preparation for the Group's future sales and commercialization efforts in the U.S. The decrease for the nine-month period ended

September 30, 2025 compared to September 30, 2024 was predominantly driven by a reduction in the headcount of the Group's Sales

and Marketing department as well as one-time costs that were incurred in 2024 for the Group's corporate re-branding, including its

new website. The increase for the three-month period ended September 30, 2025 compared to September 30, 2024 is primarily driven

by personnel costs related to share-based compensation (AGAs).

Note 19.2. Research and development

Research and development expenses break down as follows:

(amounts in thousands of euros)
RESEARCH AND DEVELOPMENT<br><br>EXPENSES FOR THE<br><br>THREE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2024 FOR THE<br><br>THREE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2025 FOR THE<br><br>NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2024 FOR THE<br><br>NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2025
Sub-contracting, studies and research 33,271 28,017 80,553 87,309
Personnel costs 4,868 23,528 14,659 34,835
Consulting and professional fees 4,156 3,029 9,644 8,877
Intellectual property fees 493 443 1,434 920
Other research and development expenses 497 399 1,646 1,421
Research and development expenses 43,286 55,416 107,936 133,362

For the nine-month period ended September 30, 2025, research and development expenses were €133,362 thousand, as compared to

€107,936 thousand for the nine-month period ended September 30, 2024, and consisted primarily of expenses related to the UC

clinical program for €92,784 thousand, the CD clinical program for €11,472 thousand, the development of new indications for

obefazimod for €6,295 thousand as well as transversal activities for €20,367 thousand. This increase was primarily due to increased

expenses relating to (i) the continued progression of the UC clinical program and Phase 3 induction trials data read-out during the third

quarter of 2025 for €8,579 thousand, (ii) new indications for obefazimod by €5,985 thousand, (iii) the CD clinical program, resulting

from the progression of the Phase 2b trials in CD by €5,385 thousand and (iv) transversal activities by €5,948 thousand, mainly due to

increased chemistry, manufacturing and control ("CMC") & supply chain costs related to the progression of clinical trials and

anticipation of future commercial launch..

These increased costs also resulted from a sharp rise in employer contributions related to share-based payments (AGAs) by €

14,815

thousand, in turn attributable to the increase in the Company's share price during the third quarter of 2025 (see Note 14) and recorded

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under the line item Personnel costs. Similar factors have driven the increase for the three-month period ended September 30, 2025

compared to September 30, 2024.

Note 19.3. General and administrative

(amounts in thousands of euros)
GENERAL AND ADMINISTRATIVE<br><br>EXPENSES FOR THE<br><br>THREE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER 30,<br><br>2024 FOR THE<br><br>THREE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER 30,<br><br>2025 FOR THE NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2024 FOR THE NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER<br><br>30, 2025
Personnel costs 4,051 21,042 15,483 31,588
Consulting and professional fees 2,229 3,542 6,077 7,245
Other general and administrative expenses 1,095 917 3,746 2,971
General and administrative expenses 7,375 25,500 25,306 41,803

For the nine-month period ended September 30, 2025, general and administrative expenses were €41,803 thousand, as compared to

€25,306 thousand for the nine-month period ended September 30, 2024. This increase was primarily due to the sharp rise in employer

contributions related to share-based payments (AGAs) by €15,075 thousands and an increase in consulting and professional fees by

€1,168 thousand, resulting from an increase in legal and professional fees and costs associated with operating as a dual-listed public

company.

Similar factors have driven the decrease for the three-month periods ended September 30, 2025 compared to September 30, 2024.

Note 20. Employees

The Group’s average workforce during the periods ended September 30, 2024 and 2025 was as follows:

HEADCOUNT FOR THE NINE<br><br>MONTHS ENDED<br><br>SEPTEMBER 30, 2024 FOR THE NINE<br><br>MONTHS ENDED<br><br>SEPTEMBER 30, 2025
France 36 40
United States 27 27
Total 63 67

Note 21. Financial gain (loss)

The financial loss breaks down as follows:

F-41

(amounts in thousands of euros)
FINANCIAL GAIN (LOSS) FOR THE THREE<br><br>MONTHS ENDED<br><br>SEPTEMBER 30,<br><br>2024 FOR THE THREE<br><br>MONTHS ENDED<br><br>SEPTEMBER 30,<br><br>2025 FOR THE NINE<br><br>MONTHS ENDED<br><br>SEPTEMBER 30,<br><br>2024 FOR THE NINE<br><br>MONTHS ENDED<br><br>SEPTEMBER 30,<br><br>2025
Interest on bond loans (2,194) (1,783) (3,559) (5,919)
Interest on convertible loan notes (1,422) (694) (4,290) (3,422)
Interest on conditional advances and PGE (12) (14) (73) (58)
Interest on royalty certificates (1,090) (1,707) (3,023) (3,758)
Interest on lease liabilities (18) (15) (43) (51)
(Increase) / decrease in derivatives fair value (699) (29,544) (1,221) (29,935)
Increase /  (decrease) in other liabilities / (assets) at fair<br><br>value through profit and loss (701) (37,354) (609) (36,015)
Increase / (decrease) in other liabilities / (assets) at<br><br>amortized cost (12,818) (11,878)
Transaction costs (1,606)
Foreign exchange losses (2,323) (9,113) (2,154) (11,419)
Other financial expense (15) (8) (49) (21)
Financial expenses (8,474) (93,051) (16,627) (102,478)
Interest income 1,983 3,361 6,794 4,410
(Increase) / decrease in derivatives fair value 1,137 3,639 139 3,620
Increase / (decrease) in other liabilities (assets) at fair<br><br>value through profit and loss 454 916
Effect of unwinding the discount related to advances<br><br>made to CROs 169 173 520 536
Day-one gain on recognition of financial liabilities 147 1,262 442 1,557
Foreign exchange gains 0 11,516 2,054 11,705
Financial income 3,436 20,404 9,949 22,743
Financial gain (loss) (5,037) (72,647) (6,679) (79,735)

Interest on bond loans consists of interests from the Kreos / Claret B and C tranches, drawn down in March and June 2024,

respectively, thus explaining the increase for the three- and nine-month periods ended September 30, 2025 compared to September 30,

2024 (see Note 15.1).

Interests on convertible loan notes corresponds to interests from the Kreos / Claret OCABSA (tranche A) and from the Height notes

(see Notes 15.1 and 15.2).

Transaction costs for the three- and nine-month periods ended September 30, 2024 mainly relate to the amortization of the prepaid

expenses related to the transaction costs of the Kreos / Claret tranche C bond loans (see Note 15.1).

Increases and decreases in the fair value of derivatives for the nine-month period ended September 30, 2025 respectively correspond to

the remeasurement of the Kreos / Claret BSA prior to their exercise and the derecognition of the Kreos / Claret MRI (see Notes 15.1,

15.2 and 15.7).

The increases in financial liabilities measured at amortized cost mainly correspond to the remeasurements of the royalty certificates

following changes in the Group's estimates of future cash flows (see Note 15.6).

The decrease and increase in other liabilities at fair value through profit or loss ("FVTPL") mainly relate to the Heights notes for the

three- and nine-month periods ended September 30, 2024 and September 30, 2025 respectively (see Note 15.2).

The increase in other assets at FVTPL for the three- and nine-month periods ended September 30, 2025 result from the revaluation of

cash equivalents measured at FVTPL.

F-42

The day-one gain on recognition of financial liabilities related to the Heights notes. The amount recorded for the nine-month ended

September 30, 2025 includes the amortization of the outstanding unamortized balance upon the conversion of the notes (see Note

15.2).

Interest income mainly relates to the invested proceeds from (i) the Group's initial public offering on the Nasdaq Global Market and

the concurrent European Private Placement from October 2023, (ii) the Kreos / Claret and Heights Financings and (iii) the Group's

public Offering from July 2025.

Foreign exchange losses for the three- and nine-month periods ended September 30, 2025 relate to the translation of cash and cash

equivalents held in U.S. dollars into the Company's functional currency as of September 30, 2025, resulting in a net loss of

€8,297 thousand, and to other realized and unrealized losses on foreign exchange transactions (see Note 11).

Foreign exchange gains for the three- and nine-month periods ended September 30, 2025 mainly relate to the €10,663 thousand gain

resulting from the favorable change in the euro to U.S. dollar exchange rate between the closing of the Group's July 2025 Offering and

the date of receipt of funds.

Note 22. Income tax

The Group incurred tax losses in the current period and prior years. As the recoverability of these tax losses is not considered probable

in subsequent periods due to the uncertainties inherent in the Group’s business, the Group has not recognized deferred tax assets

beyond deferred tax liabilities arising within the same taxable entity under the same taxable regime and with consistent timing of

reversal, after considering, if applicable, limitations in the use of deductible tax losses carried forward from prior periods applicable

under tax laws in France and in the U.S.

Note 23. Income (loss) per share

Basic loss per share is calculated by dividing income (loss) attributable to equity holders of the Company by the weighted-

average number of outstanding ordinary shares for the period.

Diluted loss per share are calculated by adjusting the weighted average number of ordinary shares outstanding to assume

conversion of all dilutive potential ordinary shares.

(amounts in thousands of euros, except share data)
BASIC AND DILUTED LOSS PER SHARE FOR THE THREE<br><br>MONTHS ENDED<br><br>SEPTEMBER 30,<br><br>2024 FOR THE THREE<br><br>MONTHS ENDED<br><br>SEPTEMBER 30,<br><br>2025 FOR THE NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER 30,<br><br>2024 FOR THE NINE<br><br>MONTHS<br><br>ENDED<br><br>SEPTEMBER 30,<br><br>2025
Weighted average number of outstanding shares 63,226,066 72,944,298 63,024,814 66,634,630
Net loss for the period (55,227) (153,358) (136,864) (254,142)
Basic and diluted loss per share (€/share) (0.87) (2.10) (2.17) (3.81)

Since net results for the three- and nine-month periods ended September 30, 2024 and 2025 are losses, potentially dilutive instruments

(BCEs, BSAs, AGAs, the OCABSA, the Kreos / Claret BSAs and the Heights notes) have been excluded from the computation of

diluted weighted-average shares outstanding because such instruments had an antidilutive impact. Consequently, diluted loss per share

is the same as the basic loss per share.

Note 24. Related parties

Except for share-based compensation plans (see Note 14), the Group has not engaged in any new transaction with its related parties

over the nine-month period ended September 30, 2025.

F-43

Note 25. Off-balance sheet commitments given and contingent liabilities

On December 12, 2024, the Group was notified of a claim from the seller of Prosynergia requesting the payment of an earn-out in

connection with the transaction. Legal proceedings are ongoing in French court. The Group considers the probability of a resource

outflow in connection with this claim to be remote, and therefore has not recorded any provision in its financial statements.

Over the period ended September 30, 2025, the Group has not entered into any significant additional off-balance sheet commitment or

amended already existing commitments. The off-balance sheet commitments given by the Group as of September 30, 2025 are

identical to December 31, 2024, with the exception of the following changes in the commitments related to CRO contracts:

In the ordinary course of business, the Group regularly uses the services of subcontractors and enters into research and partnership

arrangements with various CROs, and with public- sector partners or subcontractors, who conduct clinical trials and studies in relation

to the drug candidates. As of December 31, 2024 and September 30, 2025, the Group’s commitments amounted to respectively

€234,908 thousand and €182,597 thousand

. T

he cost of services performed by CROs is recognized as an operating expense as

incurred.

Note 26. Off-balance sheet commitments received and contingent assets

Over the nine-month period ended September 30, 2025, the Group has not received any significant additional commitment and has not

identified any contingent assets susceptible to being recognized in the future.

Note 27. Management and assessment of financial risks

The Group is exposed to interest rate risk, credit risk, foreign currency risk and liquidity risk. The Group has not identified any

significant changes in the identified credit and interest rate risks as of September 30, 2025 compared to December 31, 2024.

Liquidity risk

The remaining contractual maturities of financial liabilities as of December 31, 2024 and September 30, 2025 are presented in Note

15.8.

The Group's estimate of its cash runway as of the date of approval of these financial statements is set forth in Note 2 - Going concern.

Foreign currency risk

The Group is exposed to a risk of exchange rates fluctuations on commercial transactions performed in currencies different from the

functional currency of the Group entity recording the transactions.

As of September 30, 2025, the monetary assets and liabilities denominated in U.S. dollars held by the Company amounted to

respectively $458,254 thousand (of which $450,233 thousand corresponding to cash and cash equivalents) and $1,878 thousand.

As a result, a 10% adverse change in the closing exchange rate for the euro against the U.S. dollar would have resulted in a foreign

exchange loss of €35,337 thousand, while a 10% favorable change would have resulted in a foreign exchange gain of €43,189

thousand.

The Subsidiary does not hold any monetary asset or liability denominated in currencies different from its functioning currency (the

U.S. dollar).

F-44

At this stage, the Group has not adopted any other recurring mechanism of hedging to protect its activity against currency fluctuations.

From time to time, the Group may nevertheless subscribe currency term accounts in order to cover a commitment in currency as

described above. The Group may consider in the future using a suitable policy to hedge exchange risks in a more significant manner if

needed.

Document

Abivax Presents Third Quarter 2025 Financial Results

•Cash and cash equivalents of EUR 589.7 (as of September 30, 2025) with a cash runway into Q4 2027

PARIS, France, December 15, 2025, 10:05 p.m. CET – Abivax SA (Euronext Paris: FR0012333284 – ABVX / Nasdaq – ABVX) (“Abivax” or the “Company”), 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, announced today its key financial information for the nine months ended September 30, 2025. The unaudited interim condensed consolidated financial statements as of and for the three and nine months ending September 30, 2025, reviewed by the Company’s Board of Directors on December 11, 2025, have been reviewed by the Company’s external auditors.

Abivax provided, since the most recently released financial results press release, the following key updates on its business and operational goals in press releases published:

•On September 23, 2025, a press release titled “Abivax Announces Presentation of Late-Breaking Abstract of Obefazimod from the ABTECT Phase 3 Induction Trials at 2025 United European Gastroenterology (UEG) Meeting”

•On September 29, 2025, a press release titled “Abivax Announces Acceptance of Additional Late-Breaking Abstract from the ABTECT Phase 3 Induction Trials to be Presented at 2025 United European Gastroenterology (UEG) Meeting”

•On October 5, 2025, a press release titled “Abivax Announces Late-Breaking Presentation of 8-Week ABTECT Trial Results with Updated Safety Data”

•On October 6, 2025, a press release titled “Abivax Announces Late-Breaking Presentation of 8-Week ABTECT Induction Trial Results in Participants With and Without Prior Inadequate Response to Advanced Therapies”

•On November 3, 2025, a press release titled “Abivax Announces Patient-Reported Outcomes Data from the Phase 3 ABTECT Induction Trials of Obefazimod, Demonstrating Significant Improvements in Quality of Life for Patients with Moderate-to-Severely Active Ulcerative Colitis”

Third Quarter 2025 Financial Highlights (IFRS figures)

(Consolidated, unaudited results)

Statements of Loss* Nine months ended<br><br>September 30, Change
in millions of euros 2025 2024
Total operating income 4.1 8.1 (4.0)
Total operating expenses
of which Research and Development costs (133.4) (107.9) (25.4)
of which Sales and Marketing costs (3.4) (5.1) 1.7
of which General and Administrative costs (41.8) (25.3) (16.5)
Operating loss (174.4) (130.2) (44.2)
Financial gain (loss) (79.7) (6.7) (73.1)
Net loss for the period (254.1) (136.9) (117.3)
Statements of Financial Position* September 30, 2025 December 31, 2024 Change
--- --- --- ---
in millions of euros
Net financial position 543.3 53.4 489.9
of which other current financial assets and other current receivables and assets* 27.6 23.2 4.4
of which available cash and cash equivalents 589.7 144.2 445.5
(of which financial liabilities)** (74.0) (114.0) 40.0
Total Assets 652.1 205.2 446.8
Total Shareholders’ Equity 511.2 40.6 470.7
* Excluding prepaid expenses<br><br>** Financial liabilities include borrowings, convertible loan notes, derivative instruments, royalty certificates and other financial liabilities

*Certain figures may not add or recalculate due to the use of rounded numbers.

•Operating loss increased by EUR 44.2M to EUR 174.4M for the nine months ending September 30, 2025 compared to EUR 130.2M for the same period in 2024. Operating income, consisting predominantly of research tax credit, subsidies, and issuance, cancellation and depositary fees collected on ADS transactions, decreased by EUR 4.0M to EUR 4.1M for the nine months ending September 30, 2025 compared to EUR 8.1M for the same period in 2024. The increase in operating loss was driven by an increase in operating expenses as described further below.

•Research and development (R&D) expenses increased by EUR 25.4M to EUR 133.4M for the nine months ending September 30, 2025 compared to EUR 107.9M for the same period in 2024. This increase was predominantly driven by:

◦A EUR 8.6M increase in costs related to the Company’s ulcerative colitis (UC) clinical program and continued progression of its phase 3 trials;

◦A EUR 5.4M increase in costs related to the Company’s Crohn’s Disease (CD) clinical program, driven by the progression of Phase 2b clinical trials for obefazimod in CD;

◦A EUR 6.0M increase in costs related to other obefazimod studies;

◦A EUR 5.9M increase in transversal expenses in CMC and supply chain costs related to the progression of clinical trials and anticipation of future commercial launch; and

◦A sharp rise in employer contributions related to the Company’s equity awards, in turn explained by the increase in the Company’s share price during the third quarter of 2025, which contributed to overall increase in spend across all operating expense categories, in an amount of €14.8 million (of which €14.5 million was attributable to the three-months ended September 30, 2025 compared to September 30, 2024.

•Sales and marketing (S&M) expenses decreased by EUR 1.7M to EUR 3.4M for the nine months ending September 30, 2025 compared to EUR 5.1M for the same period in 2024. The decrease was predominantly driven by a reduction in sales and marketing headcount as well as one-time costs of €1.8 million that were incurred in the prior year period for the Company's corporate re-branding, including its new website.

•General and administrative (G&A) expenses increased by EUR 16.5M to EUR 41.8M for the nine months ending September 30, 2025 compared to EUR 25.3M for the same period in 2024. This increase was primarily due to:

◦An increase of EUR 16.1M in personnel costs, of which EUR 15.1M were employer tax and social contributions related to the Company’s AGAs, resulting from the increase in the Company’s share price during the third quarter of 2025; and

◦An increase of EUR 1.2M in spending related to legal and professional fees and other costs associated with operating as a dual-listed public company.

•For the nine months ended September 30, 2025, the EUR 79.7M financial gain (loss) was driven primarily by:

◦Increases in the fair value of the senior convertible notes (Heights Convertible Notes) issued in the August 2023 financing with Heights Capital Management and the warrants issued in August 2023 to Kreos Capital and Claret European Growth Capital (Kreos / Claret BSA) by EUR 36.0M and EUR 29.9M, respectively (driven by the increase in the Company’s share price prior to the conversion of the notes into ordinary shares);

◦Foreign exchange losses of EUR 11.4M, including EUR 9.1M non-cash impact of the revaluation of U.S. dollar-denominated cash and cash equivalents on hand as of September 30, 2025;

◦Interest expenses of EUR 9.3M in relation to borrowings and loans; and

◦Non-cash expense of EUR 15.1M in relation to royalty certificates;

◦Offset by EUR 11.7M of foreign exchange gains (including EUR 10.7M related to the Company’s July 2025 public offering), interest income of EUR 4.4M in relation to the invested proceeds from cash on hand, and EUR 3.6M of non-cash income related to the extinguishment of the Kreos / Claret minimal return indemnification liability (following the exercise of the Kreos / Claret BSA and conversion of the Kreos portion of the Tranche A OCABSA).

•The net loss for the nine months ended September 30, 2025 of EUR 254.1 million includes the following significant (greater than EUR 1.5M) non-cash expenses/(income):

in millions of euros
Share-based compensation expense 22.5
Increases in the fair value of the senior convertible notes (Heights) 36.0
Increases in the fair value of the warrants (Kreos / Claret) 29.9
Foreign exchange losses related to the revaluation of USD denominated cash and cash equivalents as of September 30, 2025 9.1
Non-cash expense from revaluation of royalty certificates 15.1
Income related to recognition of remaining day-one gain related to the extinguishment of the Heights notes (1.6)
Income related to the extinguishment of Kreos / Claret minimal return indemnification liability (3.6)

•Cash and cash equivalents as of September 30, 2025 was EUR 589.7M compared to EUR 144.2M as of December 31, 2024. The increase was primarily due to the EUR 608.1M in net proceeds, including foreign exchange gains from the period of the close of the fundraise to the receipt of cash, from the Company’s July 2025 public offering. This was partially offset by EUR 137.9M used in operations and EUR 23.4M related to principal and interest paid on the Company’s debt facilities.

•On July 28, 2025, Abivax completed its underwritten public offering of 11,679,400 American Depositary Shares, each representing one ordinary share, EUR 0.01 nominal value per share, of the Company, in the United States. The aggregate gross proceeds amounted to approximately $747.5 million, equivalent to approximately EUR 637.5 million, before deduction of underwriting commissions and offering expenses. The net proceeds, after deducting underwriting commissions and offering expenses, were approximately $700.3 million, equivalent to approximately EUR 597.2 million.

•During the nine months ending September 30, 2025, Heights Capital Management converted the Heights Convertible Notes (corresponding to the entirety of the outstanding principal amount of EUR 21.9 million) into 920,377 new ordinary shares of the Company at a conversion price of EUR 23.7674 per ordinary share in accordance with the terms and conditions of the Heights Convertible Notes. Following these share issuances, Abivax no longer holds any debt with Heights Capital Management.

•On August 6, 2025, Kreos Capital VII(UK) Limited converted its portion of the Tranche A convertible OCABSA resulting in the issuance of 785,389 ordinary shares of the Company. In addition, on the same date Kreos Capital VII Aggregator SCSp exercised its share warrants (the tranche A-B BSA and tranche C BSA) resulting in the issuance of 319,251 ordinary shares of the Company.

•On August 28, 2025, Claret European Growth Capital Fund III SCSp, exercised its share warrants (the tranche A-B BSA and tranche C BSA) resulting in the issuance of 206,662 ordinary shares of the Company.

•On November 25, 2025, Claret European Growth Capital Fund III SCSp converted its portion of the Tranche A convertible OCABSA resulting in the issuance of 392,695 ordinary shares of the Company. Following this conversion Abivax no longer holds any debt related to Tranche A of the Kreos/Claret structured debt.

•On November 28, 2025, the Company notified the bondholders of its intention to prepay in full the outstanding balances of Tranches B and C of the Kreos / Claret financing. The transaction is expected to be completed before December 31, 2025. Following this redemption, the Company will no longer hold any debt related to the entire Kreos / Claret financing.

Based on the Company’s existing cash and cash equivalents of EUR 589.7 million as of September 30, 2025, the Company expects, as of the date of issuance of the unaudited interim condensed consolidated financial statements included in the Company’s third quarter report, to be able to fund its forecasted cash flow requirements into the fourth quarter of 2027.

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About Abivax

Abivax is 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. Based in France and the United States, Abivax’s lead drug candidate, obefazimod (ABX464), is in Phase 3 clinical trials for the treatment of moderately to severely active ulcerative colitis. More information on the Company is available at www.abivax.com. Follow us on LinkedIn and on X, formerly Twitter, @ABIVAX.

Contacts:

Abivax Investor Relations

Patrick Malloy

patrick.malloy@abivax.com

+1 847 987 4878

FORWARD-LOOKING STATEMENTS

This press release contains forward-looking statements, forecasts and estimates, including those relating to the Company’s business and financial objectives. Words such as “design,” “expect,” “forward,” “future,” “potential,” “plan,” “project,” “will” and variations of such words and similar expressions are intended to identify forward-looking statements. These forward-looking statements include statements concerning or implying Abivax’s intention to and timing for repaying in full the outstanding balances of Tranches B and C of the Kreos / Claret financing, Abivax’s cash runway, and other statements that are not historical fact. Although Abivax’s management believes that the expectations reflected in such forward-looking statements are reasonable, investors are cautioned that forward-looking information and statements are subject to various risks, contingencies and uncertainties, many of which are difficult to predict and generally beyond the control of Abivax, that could cause actual results and developments to differ materially from those expressed in, or implied or projected by, the forward-looking information and statements. A description of these risks, contingencies and uncertainties can be found in the documents filed by the Company with the French Autorité des Marchés Financiers pursuant to its legal obligations including its universal registration document (Document d’Enregistrement Universel) and in its Annual Report on Form 20-F filed with the U.S. Securities and Exchange Commission on March 24, 2025 under the caption “Risk Factors.” These risks, contingencies and uncertainties include among other things, the uncertainties inherent in research and development, future clinical data and analysis, decisions by regulatory authorities, such as the FDA or the EMA, regarding whether and when to approve any drug candidate, as well as their decisions regarding labelling and other matters that could affect the availability or commercial potential of such product candidates. and the availability of funding sufficient for the Company’s foreseeable and unforeseeable operating expenses and capital expenditure requirements. Special consideration should be given to the potential hurdles of clinical and pharmaceutical development including further assessment by the Company and regulatory agencies and IRBs/ethics committees following the assessment of preclinical, pharmacokinetic, carcinogenicity, toxicity, CMC and clinical data. Furthermore, these forward-looking statements, forecasts and estimates are made only as of the date of this press release. Readers are cautioned not to place undue reliance on these forward-looking statements. Abivax disclaims any obligation to update these forward-looking statements, forecasts or estimates to reflect any subsequent changes that the Company becomes aware of, except as required by law. Information about pharmaceutical products (including products currently in development) that is included in this press release is not intended to constitute an advertisement. This press release is for information purposes only, and the information contained herein does not constitute either an offer to sell, or the solicitation of an offer to purchase or subscribe securities of the Company in any jurisdiction. Similarly, it does not give and should not be treated as giving investment advice. It has no connection with the investment objectives, financial situation or specific needs of any recipient. It should not be regarded by recipients as a substitute for exercise of their own judgment. All opinions expressed herein are subject to change without notice. The distribution of this document may be restricted by law in certain jurisdictions. Persons into whose possession this document comes are required to inform themselves about and to observe any such restrictions.