Abivax Sa · EURONEXT:ABVX
Abivax Sa — Corporate Update (June 2026)
56 slides from Abivax Sa's corporate update, Jun 29, 2026
Slide 1: ABTECT Maintenance – Supplemental Part 2 Update with Appendix
ABTECT Maintenance – Supplemental Part 2 Update with Appendix June 29, 2026
Slide 2: Agenda
Agenda Pat Malloy 01 Welcome Senior Vice President, Investor Relations Marc de Garidel 02 Opening Remarks Chief Executive Officer Fabio Cataldi, M.D. 03 Data Review: Study Context, Design & Topline Efficacy Chief Medical Officer Chris Rabbat, PhD 04 Safety Review & Exposure-Adjusted Incidence Analys
Slide 3: Webcast KOL Panel
Webcast KOL Panel Moderated Discussion and Analyst Q&A Discussion Jordan Axelrad, M.D., M.P.H Remo Panaccione, M.D., FRCPC Associate Professor of Medicine, NYU Professor of Medicine, Grossman School of Medicine, Co-Director, IBD Director, IBD Clinic Center, NYU Langone Health University of Calgary 3
Slide 4: Forward Looking Statements
Forward Looking Statements This presentation contains information pertaining to Abivax SA (“Abivax,” the “Company,” “we,” “our” or “us”). Certain statements included in this presentation that are not historical facts are forward-looking statements for purposes of the safe harbor provisions under the
Slide 5: Agenda
Agenda Pat Malloy 01 Welcome Senior Vice President, Investor Relations Marc de Garidel 02 Opening Remarks Chief Executive Officer Fabio Cataldi, M.D. 03 Data Review: Study Context, Design & Topline Efficacy Chief Medical Officer Chris Rabbat, PhD 04 Safety Review & Exposure-Adjusted Incidence Analys
Slide 6: ABTECT Maintenance Part 2: Advancing the Treatment Paradigm in UC
ABTECT Maintenance Part 2: Advancing the Treatment Paradigm in UC Part 2 further strengthens benefit-risk profile of obefazimod and de-risks regulatory pathway Obefazimod delivered best-in-disease efficacy in a highly refractory ulcerative colitis 1 population The Part 2 safety profile remained cons
Slide 7: Obefazimod Demonstrated Best-in-Disease Efficacy and a Strong Benefit-Risk Profile
Obefazimod Demonstrated Best-in-Disease Efficacy and a Strong Benefit-Risk Profile in Difficult-to-Treat Patients 37.2% of 50 mg induction non-responders achieved clinical remission at Week 44 of maintenance Strong Efficacy Results in 34.5% of 50 mg induction non-responders achieved endoscopic r
Slide 8: Agenda
Agenda Pat Malloy 01 Welcome Senior Vice President, Investor Relations Marc de Garidel 02 Opening Remarks Chief Executive Officer Fabio Cataldi, M.D. 03 Data Review: Study Context, Design & Topline Efficacy Chief Medical Officer Chris Rabbat, PhD 04 Safety Review & Exposure-Adjusted Incidence Analys
Slide 9: Part 2 Study Design: Difficult-to-Treat Population
Part 2 Study Design: Difficult-to-Treat Population Part 1 Relapsers and Induction Non-Responders 1 2 3 4 Part 2 serves as a Part 2 includes two distinct Part 2 patients are more All patients receive obefazimod supplemental dataset to Part 1 patient populations refractory and difficult to treat Maint
Slide 10: Over 55% of Part 2 Participants Previously Failed 1 or More Advanced Therapies
Over 55% of Part 2 Participants Previously Failed 1 or More Advanced Therapies Comparing Maintenance Part 1 and Part 2 Patient Populations Part 1 Part 2 Induction Responders – Part 1 Induction Non-Responders‡ – Part 2 Part 1 Relapsers* – Switch to Part 2 Double-Blind Placebo Controlled Trial Double-
Slide 11: Part 2 Patients Entered Maintenance With A Greater Inflammatory Burden Than Part 1
Part 2 Patients Entered Maintenance With A Greater Inflammatory Burden Than Part 1 Patients Baseline Characteristics at Start of Maintenance Post-Induction Focus of Today Part 1 Part 2 Induction Responders* Induction Non-responders (N=678) (N=437) Measure Maintenance Baseline Maintenance Baseline MM
Slide 12: Continued Obefazimod Treatment Delivered Unprecedented Efficacy for Non-Responders
Continued Obefazimod Treatment Delivered Unprecedented Efficacy Results for Patients who Failed to Respond After 8 Weeks Part 2: Induction Non-Responders – Exploratory Efficacy Endpoints At Week 44 of Maintenance 25 mg: All remitters were steroid-free 50 mg: Only 4 of 55 remitters remained on steroi
Slide 13: Dose Escalation From 25 mg to 50 mg Restored Disease Control
Dose Escalation From 25 mg to 50 mg Restored Disease Control in Patients Who Relapsed in Part 1, Supporting a Practical, Real-World Treatment Approach Part 1 Relapsers: Dose Escalation After Relapse on 25mg 25/50 mg (Induction) → 25 mg (Part 1) → Relapse → 50 mg (Part 2) N=33, Week 44 of Maintenance
Slide 14: Obefazimod Achieved the Highest Endoscopic Remission Rate Among All UC Therapies
Obefazimod Achieved the Highest Endoscopic Remission Rate Among All UC Therapies Obefazimod delivered transformational endoscopic remission, even in induction non-responders Obe Ph3 Obe Ph3 Maintenance Efficacy of FDA Approved UC Products: Endoscopic Remission* at 52 Weeks Induction Induction Induct
Slide 15: Agenda
Agenda Pat Malloy 01 Welcome Senior Vice President, Investor Relations Marc de Garidel 02 Opening Remarks Chief Executive Officer Fabio Cataldi, M.D. 03 Data Review: Study Context, Design & Topline Efficacy Chief Medical Officer Chris Rabbat, PhD 04 Safety Review & Exposure-Adjusted Incidence Analys
Slide 16: Contextualizing Safety Results in the Full Obefazimod Clinical Program
Contextualizing Safety Results in the Full Obefazimod Clinical Program Part 2 and Comprehensive Exposure-Adjusted Part 1 Safety Review Safety Overview Incidence Rate Analysis 16
Slide 17: Favorable Safety Profile Observed in Part 1 of the Maintenance Study
Favorable Safety Profile Observed in Part 1 of the Maintenance Study Obefazimod Part 1 Safety Results Summary Incidence rate of serious TEAEs No Signal for Serious Serious/Severe or opportunistic Infrequent Serious TEAEs similar to placebo Infections infection rate similar to placebo Low Inciden
Slide 18: Rate of Malignancies Excluding NMSCs in ABTECT Part 1 was Similar to Phase 3
Malignancies Excluding NMSCs Rate of Malignancies Excluding NMSCs in ABTECT Part 1 was Similar to Phase 3 Randomized Placebo-Controlled Maintenance Trials of Approved Agents Number and Distribution of Non-NMSC Malignancies in Part 1 was Identical to Skyrizi Malignancies Excluding NMSCs in Randomized
Slide 19: 50 mg Dose Accounted for Nearly 70% of All Patient Year Exposure in Part 2
50 mg Dose Accounted for Nearly 70% of All Patient Year Exposure in Part 2 As expected, rare events are more likely to be observed in the dose group with the greatest cumulative patient-years of exposure Patient Years Of Exposure By Dose in Part 2 Exposure Distribution How are patient-years of expos
Slide 20: Favorable Safety Profile Observed in Part 2, Consistent with Overall Experience
Favorable Safety Profile Observed in Part 2, Consistent with the Overall Obefazimod Safety Experience ABTECT Maintenance Part 2 Safety Results Obe 25 mg Obe 50 mg Summary Safety Events, n (%) N=186 N=447* Any TEAE 132 (71.0%) 307 (68.7%) TEAE leading to study drug discontinuation 21 (11.3%) 27 (6.0%
Slide 21: Obe 50 mg Accounts for 49% of Patient Year Exposure in Integrated UC Program
Obe 50 mg Accounts for 49% of Patient Year Exposure in Integrated UC Clinical Program Placebo accounts for a small minority of patient-year exposure Patient Years Overview for Exposure-Adjusted Incidence Rates Analysis Set Treatment Patient Exposure Distribution Arm Years Integrated UC Placebo 218 1
Slide 22: Increasing Size and Relevance of Dataset: Malignancies Excluding NMSCs
Malignancies Excluding NMSCs All Active Combined Malignancy Other Than NMSC Rates were Consistent with the Reference Range Across All Three Datasets Integrated UC Clinical Program Reference Range All Active (Phase 2 + Phase 3 Induction Placebo 25 mg 50 mg Based on Published Combined and Maintenance)
Slide 23: Two Malignancies Excluding NMSCs Observed in Part 2 Maintenance Trial
Malignancies Excluding NMSCs Two Malignancies Excluding NMSCs Observed in Part 2 Maintenance Trial Multiple confounding pre-existing risk factors for both malignancy cases Part 2 Malignancy Cases in Context Obefazimod 25 mg Obefazimod 50 mg Total in Part 2 Preferred Term N=186, n N=447, n N=633, n P
Slide 24: A Nonclinical Photosensitivity Finding Led to Enhanced Skin Surveillance
A Nonclinical Photosensitivity Finding Led to Enhanced Skin Surveillance in the ABTECT Phase 3 and Phase 2 OLE Protocols Photosensitivity in Context Rigorous Skin Lesion Monitoring in Skin Lesion: No difference between Nonclinical Photosensitivity Findings ABTECT and Phase 2 OLE obefazimod and place
Slide 25: No Increase in Skin Lesion Occurrence Between Placebo and Obefazimod
No Increase in Skin Lesion Occurrence Between Placebo and Obefazimod Despite Robust Surveillance Skin Lesion Summary – Phase 3 Maintenance Program Maintenance Part 1 & Part 2 Combined Patient Years of Exposure ~147 ~274 ~438 Placebo Obe 25 mg Obe 50 mg n (IR per 100 PY) n (IR per 100 PY) N (IR per 1
Slide 26: Increasing Size and Relevance of Dataset: NMSCs
NMSCs All Active Combined NMSC Rates Were Consistent With the Reference Range Across All Three Datasets Integrated UC Clinical Program Reference Range All Active (Phase 2 + Phase 3 Induction Placebo 25 mg 50 mg Based on Published Combined and Maintenance) UC Studies Increasing Size and Relevance of
Slide 27: All Four Part 2 NMSC Cases Occurred in Patients with Established Risk Factors
NMSCs All Four Part 2 NMSC Cases Occurred in Patients with Established NMSC Risk Factors Advanced age (3/4), thiopurine use (3/4), prior skin cancer history (2/4), failure of multiple advanced therapies (3/4) Part 2 NMSC Cases in Context Obefazimod 25 mg Obefazimod 50 mg Total in Part 2 Preferred Te
Slide 28: Safety Database Now Includes >1,700 Patient-Years of Exposure
Safety Database Now Includes >1,700 Patient-Years of Exposure Key safety observations from the expanded maintenance dataset Safety Analysis Summary Favorable Safety With the addition of Part 2 maintenance data, the obefazimod safety database now includes >1,700 1 Profile Maintained patient-years of
Slide 29: Agenda
Agenda Pat Malloy 01 Welcome Senior Vice President, Investor Relations Marc de Garidel 02 Opening Remarks Chief Executive Officer Fabio Cataldi, M.D. 03 Data Review: Study Context, Design & Topline Efficacy Chief Medical Officer Chris Rabbat, PhD 04 Safety Review & Exposure-Adjusted Incidence Analys
Slide 30: Abivax Conducted Regulatory Assessments with Multiple Former FDA Senior Leaders
Abivax Conducted Regulatory Assessments with Multiple Former FDA Senior Leaders Following the ABTECT Maintenance Part 1 and 2 Readouts Feedback from Four Regulatory Consultants Regarding Part 1 and 2 Data 1 Safety & Labeling 2 Dose Strategy 3 Totality of Evidence Strong support for advancing Mainten
Slide 31: Regulatory Filing Strategy: Pursue Both 25 mg and 50 mg Doses for Maintenance
Regulatory Filing Strategy: Pursue Both 25 mg and 50 mg Doses for Maintenance Top Priority Induction Maintenance 8 weeks GOAL: File for BOTH 25 mg and 50 mg as 50 mg 25 mg 50 mg Flexible dosing could maintenance enable treatment Best-in-disease Best-in-disease optimization based on treatment doses e
Slide 32: ABTECT Maintenance Part 2: Advancing the Treatment Paradigm in UC
ABTECT Maintenance Part 2: Advancing the Treatment Paradigm in UC Part 2 further strengthens benefit-risk profile of obefazimod and de-risks regulatory pathway Obefazimod delivered meaningful clinical benefit in a highly refractory ulcerative 1 colitis population The Part 2 safety profile remained c
Slide 33: Agenda
Agenda Pat Malloy 01 Welcome Senior Vice President, Investor Relations Marc de Garidel 02 Opening Remarks Chief Executive Officer Fabio Cataldi, M.D. 03 Data Review: Study Context, Design & Topline Efficacy Chief Medical Officer Chris Rabbat, PhD 04 Safety Review & Exposure-Adjusted Incidence Analys
Slide 34: Webcast KOL Panel
Webcast KOL Panel Moderated Discussion and Analyst Q&A Discussion Jordan Axelrad, M.D., M.P.H Remo Panaccione, M.D., FRCPC Associate Professor of Medicine, NYU Professor of Medicine, Grossman School of Medicine, Co-Director, IBD Director, IBD Clinic Center, NYU Langone Health University of Calgary 3
Slide 35: Agenda
Agenda Pat Malloy 01 Welcome Senior Vice President, Investor Relations Marc de Garidel 02 Opening Remarks Chief Executive Officer Fabio Cataldi, M.D. 03 Data Review: Study Context, Design & Topline Efficacy Chief Medical Officer Chris Rabbat, PhD 04 Safety Review & Exposure-Adjusted Incidence Analys
Slide 36: ABIVAX
ABIVRX
Slide 37: Thank You!
Thank You! y ABIVRX
Slide 38: Exposure-Adjusted Incidence Rate Summary Tables
EXPOSURE-ADJUSTED INCIDENCE RATE SUMMARY TABLES 38
Slide 39: Malignancy Exposure-Adjusted Incidence Rate Summary Tables
Malignancies Excluding NMSCs Malignancy Exposure-Adjusted Incidence Rate Summary Tables Phase 3 Maintenance Integrated UC Clinical Program (Phase 3 + Phase 2) Maintenance Placebo 25 mg 50 mg All Active Expected UC Phase 3 (Ind, Part 1 & 2) Placebo 25 mg 50 mg All Active Expected UC (Part 2 Only) Com
Slide 40: NMSC Exposure-Adjusted Incidence Rate Summary Tables
NMSCs NMSC Exposure-Adjusted Incidence Rate Summary Tables Phase 3 Maintenance Integrated UC Clinical Program (Phase 3 + Phase 2) Maintenance Placebo 25 mg 50 mg All Active Expected UC Phase 3 (Ind, Part 1 & 2) Placebo 25 mg 50 mg All Active Expected UC (Part 2 Only) Combined Background + Phase 2 Pr
Slide 41: Additional Efficacy
a ADDITIONAL EFFICACY ABIVRX
Slide 42: Obefazimod Also Recaptured Response in Patients who Relapsed After Placebo
Obefazimod Also Recaptured Response in Patients who Relapsed After Being Randomized to Placebo in Part 1 and Switched to 50 mg in Part 2 Part 1 Relapsers: Relapse After Treatment Interruption 25/50 mg (Induction) → Placebo (Part 1) → Relapse →50 mg (Part 2) N=109, Week 44 of Maintenance 69.7% 54.1%
Slide 43: Phase 3 Induction and Phase 3 Part 2 Patient Cases
PHASE 3 INDUCTION AND PHASE 3 PART 2 PATIENT CASES 43
Slide 44: Malignancy in Phase 3 Induction
Malignancies Excluding NMSCs Malignancy in Phase 3 Induction Months of Medical Gender/ Obefazimod Treatment Investigator Preferred Term Obe Location Prior UC Treatment History of Medical History & Summary Age Duration Assessment* Exposure Cancer Prostatic hyperplasia (benign prostatic hyperplasia) t
Slide 45: Part 2: Malignancies other than non-melanoma skin cancers
Malignancies Excluding NMSCs Part 2: Malignancies other than non-melanoma skin cancers (non-NMSC) Medical Gender/ Obefazimod Treatment Months of Investigator Preferred Term Location Prior UC Treatment History of Medical History & Summary Age Duration Obe Exposure Assessment* Cancer MH of thrombocyth
Slide 46: All four Part 2 NMSC cases occurred in patients with established risk factors
NMSCs All four Part 2 NMSC cases occurred in patients with established NMSC risk factors Advanced age (3/4), thiopurine use (3/4), prior skin cancer history (2/4), failure of multiple advanced therapies (3/4) Medical Gender/ Obefazimod Treatment Months of Investigator Preferred Term Location Prior U
Slide 47: Reported Part 2 acute pancreatitis events and relevant clinical context
Reported Part 2 acute pancreatitis events occurred in patients with medical history and relevant clinical context Case 1: 25 mg Case 2: 50 mg Age: 50+ Location: Central Europe Age: 35+ Location: Eastern Europe Induction: PBO (8 wks) Treatment duration: Induction: 50 mg (8 wks) Treatment duration: Ma
Slide 48: Deaths Reported in Competitor Phase 3 Trials for Context
Deaths Reported in Competitor Phase 3 Trials for Context Obefazimod: One Non-Treatment Related Death in ABTECT Maintenance Part 2 Phase 3 UC Program Drug (Brand) (Induction + Maintenance) Details of Non-Treatment Related Death in ABTECT Part 2 Active Drug – 52 weeks Death (n) Treatment Arm 25 mg Age
Slide 49: Phase 2 Patient Years and Cases
PHASE 2 PATIENT YEARS AND CASES 49
Slide 50: Long-term Phase 2 experience included ~858 patient years of exposure
Phase 2 Long-term Phase 2 experience included ~858 patient years of exposure TOTAL PHASE 2 PATIENT YEARS (PYs)* ~858 PY of Obe Exposure 50 mg = ~404 PY, 25 mg = ~434 PY, PBO = ~20PY MH = Medical History; Patient Years for this analysis included obefazimod exposure only; *As of May 2026 50 Data on Fi
Slide 51: Malignancy / NMSC in Phase 2 Studies
Malignancies Excluding NMSCs NMSCs Malignancy / NMSC in Phase 2 Studies Medical Gender/ Obefazimod Treatment Months of Investigator Preferred Term Location Prior UC Treatment History of Medical History & Summary Age Duration Obe Exposure Assessment* Cancer Approximately 14 months after treatment ini
Slide 52: Protocol
52 PROTOCOL ABIVRX
Slide 53: ABTECT Phase 3 and Phase 2b OLE protocols incorporated enhanced skin lesion surveillance
ABTECT Phase 3 and Phase 2b OLE protocols incorporated enhanced skin lesion surveillance following pre-clinical photosensitivity findings Initial Protocol ABX464-108 CSP, v1.0, released 01-Sep-2021 Obefazimod Initial Obefazimod Updated Protocol Feature (ABX-484-108 v1.0) (ABTECT/108 v3.0) Skin lesio
Slide 54: Incidence Rates Calculations
INCIDENCE RATES CALCULATIONS 54
Slide 55: How Malignancy Incidence Rates (per 100 Patient-Years) Were Derived
Malignancies Excluding NMSCs How Malignancy Incidence Rates (per 100 Patient-Years) Were Derived 1 Published Sources 2 Converted to 100 Patient Years 3 Derived Benchmark Range Long MD, Martin CF, Pipkin CA, et al. Risk of melanoma and nonmelanoma skin cancer among patients with inflammatory bowel
Slide 56: How NMSC Incidence Rates (per 100 Patient-Years) Were Derived
NMSCs How NMSC Incidence Rates (per 100 Patient-Years) Were Derived 1 Published Sources 2 Converted to 100 Patient Years 3 Derived Benchmark Range NMSC Incidence (as Incidence Published NMSC incidence in IBD/UC Source Population Calculation population is generally on the order of: reported) (per 100