obefazimod (ABX464) / Abivax - LARVOL DELTA

EQ504, a Potent AhR Modulator, Promotes Epithelial Repair and Barrier Restoration Compared to Clinically Validated AhR Agonists. (IMMUNOLOGY 2026) - "These findings demonstrate that EQ504 is a potent AhR agonist with superior epithelial repair and barrier-stabilizing activity compared to obefazimod. The ability of EQ504 to promote IL-22 responsiveness while reducing CLDN2 expression highlights functional differentiation among AhR-targeting therapies and supports its development as a promising treatment for inflammatory mucosal diseases."

Clinical • Gastroenterology • Gastrointestinal Disorder • Immunology • Inflammation • Inflammatory Bowel Disease • Ulcerative Colitis • CLDN2 • IL22 • IL2RA

EQ504: A Novel AhR Modulator That Promotes Immune Tolerance Through Il-10 and Il-22 Cytokine Release (IMMUNOLOGY 2026) - "Despite its therapeutic potential inflammatory bowel disease (IBD), clinical development of AhR modulators has been limited by the lack of potent, selective and drug-like molecules. We evaluated EQ504, a novel small-molecule AhR modulator derived from the endogenous ligand ITE and obefazimod, a clinically validated molecule in IBD. These findings identify EQ504 as a potent next generation AhR modulator with a unique immunoregulatory profile. EQ504 promotes Tr1mediated immune tolerance and anti-inflammatory macrophage polarization, mechanisms highly relevant to the treatment of IBD."

Gastroenterology • Gastrointestinal Disorder • Immunology • Inflammation • Inflammatory Bowel Disease • FOXP3 • GZMB • IL10 • IL1B • IL22 • IL6 • TNFA

R&D Expenses (GlobeNewswire) - "Research and development ('R&D') expenses increased by €31.2 million to €177.8 million (70.9% of operating expenses) in 2025 compared to €146.5 million (79.0% of operating expenses) in 2024. This increase was predominantly driven by expenses related to:...A €10.2 million increase related to the Company’s Crohn’s disease ('CD') clinical program, driven by the progression of Phase 2b clinical trials for obefazimod in CD; and A €4.1 million increase related to new indications (including combination therapy) for obefazimod; and A €1.6 million increase related to the Company’s ulcerative colitis ('UC') clinical program, driven by the continuation of Phase 3 clinical trials for obefazimod in UC..."

Commercial • Crohn's disease • Ulcerative Colitis

Data Safety Monitoring Board (DSMB) Update for ABTECT Phase 3 Trials (GlobeNewswire) - "On March 18, 2026, the independent Data Safety Monitoring Board ('DSMB') completed a safety review of the ongoing Phase 3 ABTECT-UC maintenance trial and reported no new safety signals. Nearly 90% of enrolled participants have completed the 44-week treatment period. This positive update supports the continued advancement of the program as the Company remains on track to report topline results from its ABTECT-UC maintenance trials in late Q2 2026."

DSMB • P3 data: top line • Ulcerative Colitis

Impact of prior advanced therapy inadequate response by drug class on symptomatic improvement with obefazimod in patients with moderately to severely active ulcerative colitis: pooled analysis of ABTECT Phase 3 induction trials (ECCO-IBD 2026) - P3 | "Rates of symptomatic remission and symptomatic response were evaluated across subgroups of ATIR pts, including 1 TNF inhibitor only (TNFi-IR), vedolizumab only (Vedo-IR), a TNFi + Vedo (TNFi/Vedo-IR) only, a TNFi + Vedo + ustekinumab (TNFi/Vedo/Uste-IR) only, and ustekinumab (Uste-IR) or a JAK inhibitor (JAK-IR) in any line of therapy. 2: Proportion of ATIR patients achieving symptomatic response from week 1 to week 8 – pooled ABTECT trials Conclusion In this pooled analysis of ABTECT trials, Obe demonstrated symptomatic improvements in pts with UC as early as the first weeks of treatment, irrespective of prior inadequate response to any class of AT. Symptomatic remission continued to increase through W8 across all ATIR subgroups without plateau, indicating potential for additional gains beyond W8."

Metastases • P3 data • Retrospective data • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis

Efficacy and safety of obefazimod in patients with moderately to severely active ulcerative colitis: results from two, Phase 3, randomised, double-blind, (BWG 2026) - P3 | "In both ABTECT induction trials, primary and secondary endpoints were met; obe treatment led to statistically significant improvements in clinical, endoscopic, symptomatic and combined endoscopic-histologic endpoints at week 8. Obe was well tolerated with no new safety signals identified."

Clinical • P3 data • Gastroenterology • Gastrointestinal Disorder • Immunology • Infectious Disease • Inflammatory Bowel Disease • Ulcerative Colitis

Efficacy of obefazimod in ABTECT Phase 3 induction trials: results of 8-week therapy in subsets of patients with and without prior inadequate response to advanced therapies. (BWG 2026) - P3 | "Among AT-IR-Yes and AT-IR-No subgroups, improvements in clinical, endoscopic, symptomatic and combined endoscopic-histologic measures were observed in pts treated with Obe at week 8 relative to PBO in ABTECT-1, ABTECT-2, and in the pooled analysis. Improvements vs. PBO in clinical response were observed in a pooled analysis in AT-IR-Yes JAKi-IR pts and across lines of therapy up to 4+ AT-IR."

Clinical • Metastases • P3 data • Gastroenterology • Gastrointestinal Disorder • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis

Phase 1 Study to Evaluate Pharmacokinetics, Relative Bioavailability, Palatability of Obefazimod Minitablet Formulation (clinicaltrials.gov) - P1 | N=44 | Not yet recruiting | Sponsor: Abivax S.A.

New P1 trial

IMPACT OF OBEFAZIMOD TREATMENT ON HISTOLOGIC AND COMBINED HISTOLOGIC-ENDOSCOPIC OUTCOMES IN PATIENTS WITH MODERATELY TO SEVERELY ACTIVE ULCERATIVE COLITIS: RESULTS FROM THE ABTECT-1 AND ABTECT-2 PHASE 3, DOUBLE-BLIND, PLACEBO-CONTROLLED INDUCTION TRIALS (DDW 2026) - No abstract available

Clinical • P3 data • Gastroenterology • Gastrointestinal Disorder • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis

Continued efficacy improvement beyond the induction period with once-daily obefazimod: week 8 to week 48 outcomes from the Phase 2b open-label maintenance study in patients with moderately to severely active ulcerative colitis, stratified by prior advanced-therapy exposure (ECCO-IBD 2026) - P3 | "Conclusion Obe-treated pts who achieved clinical response at W8 demonstrated continued improvement across all efficacy endpoints at W48, including clinical remission, independent of prior AT experience. Since both the Phase 2 and 3 studies enrolled similar populations of both AT-naïve and AT-experienced pts (including pts who failed prior AT), these findings provide relevant context for the ongoing Phase 3 maintenance trial."

Clinical • Metastases • P2b data • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis

Pooled analysis of efficacy and safety of once-daily oral obefazimod in European patients from the ABTECT Phase 3, double-blind, placebo-controlled induction trials (ECCO-IBD 2026) - P3 | "No signal was observed for serious/severe and opportunistic infections or malignancies. Conclusion In the European population included in the ABTECT induction trials, obefazimod demonstrated consistent efficacy and safety comparable to the overall study population."

P3 data • Retrospective data • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis

Early symptomatic improvement with obefazimod in patients with moderately to severely active ulcerative colitis: pooled results from the ABTECT-1 and ABTECT-2 Phase 3, double-blind, placebo-controlled induction trials (ECCO-IBD 2026) - P3 | "Greater proportions of pts receiving Obe achieved symptomatic response from W1 and symptomatic remission from W2. Conclusion In the ABTECT induction trials, both Obe doses demonstrated rapid and clinically meaningful symptoms improvement versus PBO, evident as early as W1."

Clinical • P3 data • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis

Impact of prior inadequate response to advanced therapy (ATIR) on the efficacy of obefazimod in patients with moderately to severely active ulcerative colitis: results in subgroups including or excluding patients with prior JAK-IR from ABTECT Phase 3 induction trials (ECCO-IBD 2026) - P3 | "Conclusion In this pooled analysis of ABTECT trials, obefazimod showed rapid and nominally significant efficacy across clinical, endoscopic, and symptomatic endpoints in all ATIR pts. Similar outcomes were observed in the ATIR subgroup excluding JAK-IR in any line of therapy."

Clinical • Metastases • P3 data • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis

Integrated summary of safety of obefazimod in Phase 3 ABTECT induction trials (ECCO-IBD 2026) - P3 | "Serious, severe, or opportunistic infections or malignancies were rarely reported. Conclusion This integrated safety analysis of the two completed Phase 3 ABTECT induction trials showed a favorable safety and tolerability profile of obefazimod as observed in Phase 2 trials."

Clinical • P3 data • Inflammatory Bowel Disease • Ulcerative Colitis

Impact of age of subjects on the efficacy and safety of once-daily oral obefazimod in moderately to severely active ulcerative colitis: week 8 results from the ABTECT-1 and ABTECT-2 Phase 3, double-blind, placebo-controlled induction trials (ECCO-IBD 2026) - P3 | "No signal was observed for serious, severe, or opportunistic infections or malignancies. Conclusion In both ABTECT induction trials, obefazimod demonstrated consistent efficacy and safety across age subgroups with no new or unexpected safety findings."

Clinical • P3 data • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis

Impact of baseline Mayo endoscopic subscore on the efficacy of once-daily oral obefazimod in moderately to severely active ulcerative colitis: week 8 results from the two Phase 3 ABTECT induction trials (ECCO-IBD 2026) - P3 | "Conclusion In both ABTECT induction trials, obefazimod demonstrated clinical meaningful improvements irrespective of baseline MES. Numerically greater efficacy rates were observed in pts with baseline MES2 vs MES3."

Clinical • P3 data • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis

Impact of obefazimod treatment on histologic and combined histologic-endoscopic outcomes in patients with moderately to severely active ulcerative colitis: results from the ABTECT-1 and ABTECT-2 Phase 3, double-blind, placebo-controlled induction trials (ECCO-IBD 2026) - P3 | "In a pooled analysis, higher proportions of pts receiving either Obe-25 or Obe-50 versus PBO achieved all endoscopic and histologic endpoints (endoscopic improvement: Obe-25-PBO difference=21.9%; Obe-50-PBO difference=26.6% - histologic improvement: Obe-25-PBO difference=19.6%; Obe-50-PBO difference=22.8%), and combined endoscopic-histologic with nominal significance, including the most stringent endpoint of HEMR (Table 1). Conclusion In ABTECT induction trials, Obe treatment led to clinically meaningful improvements in endoscopic, histologic, and combined histologic-endoscopic endpoints at W8."

Clinical • P3 data • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis

Impact of concomitant use of corticosteroids on efficacy and safety of obefazimod at week 8 of induction trials in patients with moderately to severely active ulcerative colitis: results from the ABTECT-1 and ABTECT-2 Phase 3, double-blind, placebo-controlled induction trials (ECCO-IBD 2026) - P3 | "No signal was observed for serious, severe, or opportunistic infections or malignancies. Conclusion In both ABTECT induction trials, Obe demonstrated consistent efficacy and safety irrespective of baseline CS status."

Clinical • P3 data • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis

Obefazimod mechanism of action (ECCO-IBD 2026) - "Sponsored by Abivax"

Inflammatory Bowel Disease

Obefazimod shows first evidence of anti-fibrotic activity in preclinical models of inflammatory bowel disease (ECCO-IBD 2026) - "Nintedanib, omipalisib and upadacitinib were used as comparators...2B) and collagen deposition was reduced by ~52% with day 5 dosing and ~42% with day 20 dosing in the Sirius Red assay, whereas thalidomide as a positive control achieved ~24%...Initial in vivo mouse data, aligned with the in vitro findings, indicate that Obe may act in a unique way on both intestinal inflammation and fibrosis. These promising results provide a strong rationale to further investigate Obe’s anti-fibrotic potential in the ongoing phase 2b Crohn’s disease trial (NCT#06456593)."

Preclinical • Crohn's disease • Immunology • Inflammation • Inflammatory Bowel Disease • Ulcerative Colitis • TGFB1

Impact of baseline body mass index (BMI) on efficacy of obefazimod in patients with moderately to severely active ulcerative colitis: results from the Phase 3 ABTECT induction trials (ECCO-IBD 2026) - P3 | "Similar results were observed with all other efficacy endpoints evaluated (Table). Conclusion In both ABTECT induction trials, Obe-25 and Obe-50 demonstrated clinically meaningful improvements in clinical, endoscopic, symptomatic, and combined endoscopic-histologic endpoints at week 8, with similar effect sizes, irrespective of baseline BMI."

Clinical • P3 data • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis

Improvements in patient-reported work productivity and activity impairment among patients with moderately to severely active ulcerative colitis (UC) treated with obefazimod induction therapy: pooled results from the 8-week ABTECT-1 and ABTECT-2 Phase 3, double-blind, placebo-controlled induction trials (ECCO-IBD 2026) - P3 | "Greater proportions of Obe-treated pts also achieved a MWPC for the presenteeism and activity impairment domains vs PBO (Table). Conclusion Obe markedly improved work productivity and reduced activity impairment in pts with moderately to severely active UC across both ABTECT induction trials."

Clinical • P3 data • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis

Obefazimod enhances miR-124 expression in blood and colon tissue and reduces the key inflammatory cytokines IL-17A and IL-6 in serum of patients with moderate-to-severely active ulcerative colitis: results from the Phase 3 ABTECT induction trials (ECCO-IBD 2026) - P3 | "Conclusion In the ABTECT induction trials conducted in pts with UC, Obe was associated with enhanced expression of miR-124 and nominally statistically significant reductions in the pro-inflammatory cytokines IL-17A and IL-6. These findings are consistent with the Phase 2 trial results and reflect restoration of immune homeostasis."

Clinical • P3 data • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis • IL17A • IL6

Impact of prior inadequate response to advanced therapies on early symptomatic improvement with obefazimod induction in moderately to severely active ulcerative colitis: results from the two Phase 3 placebo-controlled ABTECT induction trials (ECCO-IBD 2026) - P3 | "Conclusion In ABTECT trials, Obe-treated pts rapidly achieved symptomatic relief (either response or remission) regardless of prior ATIR, including a large number of pts previously treated with JAKi. No evidence of a plateau was observed through end of induction at W8 in all ATIR-Yes subgroups."

Clinical • Metastases • P3 data • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis

Improvements in patient-reported bowel urgency and nocturnal bowel movements among patients with moderately to severely active ulcerative colitis (UC) treated with obefazimod induction therapy: pooled results from the 8-week ABTECT-1 and ABTECT-2 Phase 3, double-blind, placebo-controlled induction trials (ECCO-IBD 2026) - P3 | "Results for BU and NBM were consistent across both trials. Conclusion Obe markedly improved BU and NBM in pts with moderately to severely active UC across both ABTECT induction trials with improvements observed as early as 2 weeks."

Clinical • P3 data • Immunology • Inflammatory Bowel Disease • Ulcerative Colitis