Obefazimod

Abivax Announces Positive Pre-NDA Interaction with the FDA for Obefazimod Company remains on track to submit its first New Drug Application for obefazimod for the treatment of moderately to severely active ulcerative colitis by the end of 2026 PARIS, France – July 30, 2026 – 10:05 p.m. CEST – 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, today announced the successful completion of its positive pre-New Drug Application (NDA) interaction with the U.S. Food and Drug Administration (FDA) for obefazimod for the treatment of adults with moderately to severely active ulcerative colitis (UC). Constructive FDA feedback resulted in alignment on the Company's planned NDA submission strategy and supported the planned content and format of the NDA submission. Abivax remains on track to submit its first NDA for obefazimod by the end of 2026. Marc de Garidel, MBA, Chief Executive Officer of Abivax said: “Achieving alignment with the FDA on our NDA submission strategy marks an important milestone as we prepare to submit Abivax's first New Drug Application for obefazimod. We appreciate the Agency's constructive feedback, which reinforces our confidence in the path toward filing. This progress builds on the positive Phase 3 ABTECT program results announced earlier this year, which continue to support obefazimod's potential in ulcerative colitis as we work toward completing our NDA submission by the end of 2026." ezstandalone.cmd.push(function () { ezstandalone.showAds(131); }); 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. Contact: Patrick Malloy SVP, Investor Relations Abivax SA patrick.malloy@abivax.com Media Contact: LifeSci Communications Karissa Baltz, Ph.D. Associate Director LSC_ABIVAX@lifescicomms.com FORWARD-LOOKING STATEMENTS This press release contains forward-looking statements, forecasts and estimates, including those relating to the Company’s business. Words such as “anticipate,” “expect,” “on track,” “potential,” “will” and variations of such words and similar expressions are intended to identify forward-looking statements. These forward-looking statements include statements concerning the potential therapeutic benefit of obefazimod and obefazimod’s potential to be a first-in-class therapy for ulcerative colitis, the timing of regulatory filings including an NDA submission for obefazimod in ulcerative colitis, the potential U.S. commercialization of obefazimod, 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 for the fiscal year ended December 31, 2025 filed with the U.S. Securities and Exchange Commission on March 23, 2026, 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 labeling 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 for 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. Attachment 2026_07_30_Abivax Announces Positive Pre-NDA Interaction with FDA for Obefazimod

Positive proof-of-concept clinical data show substantial improvements in visual acuity in limbal stem cell deficiency ( LSCD) patients treated with CSB-001 Pivotal studies for CSB-001 in LSCD planned for 1H 2027 Series B funds Claris through pivotal development and supports pre-commercialization activities Stephen Brady appointed President and Chief Executive Officer, Brian Baum named Chief Commercial Officer, and Marc de Garidel appointed Chairman of the Board ezstandalone.cmd.push(function () { ezstandalone.showAds(131); }); JERSEY CITY, N.J., July 28, 2026 (GLOBE NEWSWIRE) -- Claris Biotherapeutics, Inc. , a late-stage biopharmaceutical company dedicated to advancing transformative therapies for sight-threatening conditions where limited or no treatment options exist, today announced multiple key milestones, including the close of a $118 million Series B financing and key executive and board appointments. These catalysts are designed to accelerate the company’s next phase of growth as it advances CSB-001 (oremepermin alfa ophthalmic solution) based on positive proof-of-concept data towards the planned initiation of pivotal studies in 1H 2027 in patients with limbal stem cell deficiency (LSCD), a blinding disease impacting the ocular surface, representing an area of high unmet need where no approved drug therapy exists. Financing Details The $118M Series B financing was co-led by new investors Samsara Biocapital and Catalio Capital Management, and joined by Adage Capital Management, Sofinnova Investments, Aisling Capital, and ADAR1 Capital Management, with continued support from all existing investors, Novo Holdings, Janus Henderson Investors, and Mass General Brigham Ventures. Proceeds from the fundraise will be used to complete Claris’ ongoing clinical trials in patients with LSCD, including a proof-of-concept study evaluating CSB-001 and a non-interventional natural history study. The financing will also fund the company through a planned pivotal program of CSB-001 in patients with LSCD, scheduled to start in 1H 2027, and enable pre-commercialization activities. CSB-001 targets the underlying pathophysiology of LSCD by promoting corneal epithelial regeneration while modulating inflammation and fibrosis. Clinical data generated to date have demonstrated substantial improvements in visual acuity. Claris expects to report its proof-of-concept results in LSCD during the second half of 2026. In connection with the financing, Stephen Brady, President and CEO of Claris, Mike Dybbs, Ph.D., Partner at Samsara Biocapital, Matthew Hobson, Ph.D., Principal at Catalio Capital Management, and Maha Radhakrishnan, M.D., Executive Partner at Sofinnova Investments, joined the board of directors. Claris Appointments Stephen Brady, President & CEO , has nearly 30 years of operational, transactional, and board experience spanning corporate strategy, M&A, business development, and finance across public and private life sciences companies. Prior to Claris, Mr. Brady was the Chairman of the Board and CEO of Tempest Therapeutics, and prior to this position, he was executive vice president of strategy and finance at Immune Design and played a key role in the company's IPO, financings, licensing deals, and eventual sale to Merck. Earlier in his career, he held progressively senior roles at several biopharmaceutical companies, including vice president of corporate development at Proteolix. In this position, Mr. Brady led Proteolix’s business development and strategic efforts that culminated in the company’s sale to Onyx Pharmaceuticals. Proteolix’s lead asset, Kyprolis ® (carfilzomib), subsequently became the cornerstone of Onyx and a principal driver of Amgen’s $10.4 billion acquisition of Onyx. Mr. Brady currently serves on the Board of Directors of Claris and the Biotechnology Innovation Organization (BIO). Brian Baum, CCO, brings to Claris more than 20 years of program and lifecycle management, commercial strategy, marketing, market access, commercial operations, and specialty product launch experience in biopharma. Prior to Claris, Mr. Baum served as Senior Vice President at Dompé Pharmaceuticals and led critical commercial initiatives that supported the successful U.S. launch and growth of Oxervate ® , a recombinant human nerve growth factor approved in 2018 for neurotrophic keratitis, a rare and serious eye disease with no prior FDA-approved therapies. As a senior commercial leader, Mr. Baum played a key role in driving Oxervate’s growth, with annual U.S. sales surpassing $1.1 billion in 2024. Prior to Dompé, Mr. Baum spent ten years at Genentech in a range of U.S. and global commercial leadership roles, including supporting the launch and commercialization of Lucentis ® across three major retinal indications: wAMD, RVO, and DME. Marc de Garidel, Chairman, is a recognized biotech entrepreneur and global pharmaceutical executive with a distinguished track record of building and scaling innovative healthcare companies, advancing breakthrough therapies, and creating substantial shareholder value through organic growth and strategic M&A across the biotechnology sector. Since May 2023, Mr. de Garidel has served as CEO of Abivax, leading the development of obefazimod for ulcerative colitis and driving exceptional corporate growth, from a $500 million to a $14 billion company in over three years. Prior to Abivax, he was CEO of CinCor Pharma from 2020 to 2023, where he successfully led the company through its acquisition by AstraZeneca. CinCor’s lead therapy was subsequently approved by the FDA as a first-in-class treatment for resistant hypertension. From 2018 to 2020, Mr. de Garidel served as CEO of Corvidia Therapeutics, overseeing its strategic growth and successful acquisition by Novo Nordisk. Earlier in his career, he served as CEO of Ipsen from 2010 to 2016, where he transformed the company into a leading global oncology player through the expansion of Somatuline and the landmark ex-U.S. licensing agreement for Cabometyx. Mr. de Garidel began his career at Eli Lilly and Company before spending 15 years at Amgen in senior international leadership roles. He has also served as Chairman of Ipsen since late 2010. “I’m thrilled to join Claris at such a pivotal moment in the company’s evolution,” said Mr. Brady, President and CEO of Claris. “The strong interest in CSB-001 reflects both its promise for patients and commercial potential. With the company financed through Phase 3 and the team in place to execute, we're ready to advance CSB-001 from a position of strength. The prospect of significantly improving vision with a convenient eye drop is a tremendous advance, and I'm energized by the opportunity to take on a blinding disease like LSCD.” Marc de Garidel, Chairman of Claris Bio, added, “Claris is entering a defining period in its growth. In addition to welcoming Steve and Brian to Claris’ leadership team, I’d like to thank our founding CEO, Clarke Atwell, for his years of diligence in building the team and advancing the science underlying CSB-001, which allows us to approach this watershed moment with confidence. We look forward to continuing our work to advance CSB-001 in patients with limbal stem cell deficiency and lead the company through its next phase as we approach commercialization.” About LSCD and CSB-001 Limbal stem cell deficiency (LSCD) is a disease of the eye in which specialized stem cells that continuously replenish and repair the corneal surface are damaged or destroyed, leading to severe vision loss or blindness. CSB-001 (oremepermin alfa ophthalmic solution) contains recombinant human deleted hepatocyte growth factor (dHGF) as its active ingredient. By promoting corneal epithelial regeneration while modulating inflammation and fibrosis, CSB-001 is intended to address the underlying pathophysiology of LSCD. Clinical data to date demonstrate substantial improvements in visual acuity in LSCD patients treated with CSB-001. If approved, CSB-001 has the potential to become the first pharmacologic treatment for LSCD, providing a reliable, accessible, and scalable non-surgical treatment option. Claris and Kringle Pharma, Inc., a company developing oremepermin alfa for non-ophthalmic indications, have a safety-data sharing collaboration that has enabled a more efficient development of oremepermin alfa. Estimates indicate that at least 30,000 LSCD patients in the U.S. are actively being managed by an eye care professional, although given the lack of diagnosis, the number is likely larger. Ongoing and Planned CSB-001 Clinical Studies Proof-of-Concept Study. An open-label clinical study evaluating the safety and efficacy of CSB-001 eyedrops in 63 LSCD subjects is ongoing. Subjects receive CSB-001 investigational eye drops in either one or both eyes over 20 weeks beginning on Day 0, or at Week 20 after a 20 week observational period. Completion of dosing is followed by an observational period. More information can be found at clinicaltrials.gov (NCT06452316): Pivotal Studies. In 1H 2027, Claris plans to initiate two pivotal studies evaluating the safety and efficacy of CSB-001 compared to vehicle in a total of approximately 400 LSCD subjects. The primary efficacy endpoint will be visual acuity supported by anatomical endpoints. Non-Interventional Study. To prepare for the planned pivotal studies, Claris is currently conducting a prospective non-interventional study in subjects with LSCD. This study will provide insights into the natural history of LSCD and characterize real-world LSCD management patterns, and identify and qualify investigative sites and potential study participants for the planned pivotal studies. More information can be found at clinicaltrials.gov (NCT07636590): About Claris Bio Claris Biotherapeutics is a late-stage biopharmaceutical company dedicated to advancing transformative therapies for sight-threatening conditions where no or limited treatment options exist. With an initial focus on limbal stem cell deficiency (LSCD), a blinding disease, we are developing the first pharmacologic treatment with the potential to provide a reliable, accessible, and scalable non-surgical treatment option, while moving medical management beyond today's palliative care and towards meaningful improvements in vision and ocular surface health. Our near-term plan is to advance our lead therapeutic candidate, CSB-001 (oremepermin alfa ophthalmic solution), into LSCD pivotal studies in the first half of 2027, with a longer-term goal to become a leader in developing new therapies that improve vision and change patients’ lives. Foundational intellectual property for Claris was based on the scientific work of Drs. Reza Dana, MD, MSc, MPH, and Sunil Chauhan, DVM, PhD., both from the Massachusetts Eye and Ear and the Harvard Medical School Department of Ophthalmology. To learn more, visit . Media Contact Jordyn Temperato LifeSci Communications jtemperato@lifescicomms.com