Media Update: AAD: new data advance Sanofi’s scientific leadership across innovative treatments for inflammatory skin diseases

AAD: new data advance Sanofi’s scientific leadership across innovative treatments for inflammatory skin diseases New amlitelimab phase 2 data show impact on symptoms for patients with moderate-to-severe AD Positive Dupixent data include a late-breaking oral presentation featuring phase 2/3 data evaluating the efficacy and safety of Dupixent in patients with BP Paris, February 28, 2025 . Sanofi will present 26 abstracts, including one late-breaking and five additional oral presentations, across approved and investigational medicines at the American Academy of Dermatology (AAD) Annual Meeting in Orlando, FL, US from March 7 – 11, 2025. Presentations in partnership with Regeneron include studies evaluating Dupixent in patients with bullous pemphigoid (BP), atopic dermatitis (AD), chronic spontaneous urticaria and prurigo nodularis (PN). New analyses evaluating Sanofi’s pipeline medicine amlitelimab, an anti-OX40-ligand monoclonal antibody, will also be presented, including long-term (52-week) results from the STREAM-AD phase 2b study in adult patients with moderate-to-severe AD, and the first interim results from the RIVER-AD phase 2 study in adult patients who did not initially achieve clinical response in Part 1 of the STREAM-AD study at 24 weeks. Alyssa Johnsen, MD, PhD Global Therapeutic Area Head, Immunology and Oncology Development “Our breadth of data at AAD demonstrates our commitment to patients and advancing treatments for an unmatched number of type 2 inflammatory skin conditions driven by intense itch. The Dupixent data being shared reinforce its clinical evidence across skin diseases, including results from a phase 2/3 study in patients with bullous pemphigoid. Additionally, we are excited to share new data highlighting the potential of our novel anti-OX40-ligand, amlitelimab, in atopic dermatitis, which offers a unique mechanism of action that could help normalize the overactive immune system and restore immune balance without T-cell depletion.” Notable presentations include: Dupixent Key presentations highlighting data from the Dupixent clinical program will be featured, including a late-breaking oral presentation: LIBERTY-BP ADEPT phase 2/3 study: results evaluating the efficacy and safety of Dupixent in patients with moderate-to-severe BP. Immunology pipeline New data evaluating amlitelimab in patients with moderate-to-severe AD will also be presented, including: STREAM-AD phase 2b study: 52-week results evaluating the impact of amlitelimab on maintenance of itch response in AD. RIVER-AD phase 2 study: first interim results assessing the safety and efficacy of amlitelimab in patients with AD at 28 weeks that did not achieve clinical response in the STREAM-AD study at 24 weeks. Amlitelimab is an investigational medicine and its safety and efficacy have not been evaluated by any regulatory authority. Complete list of AAD presentations: Presenting author Abstract title Presentation details Atopic dermatitis Beck Dupilumab Treatment Significantly Reduces Age-Dependent Total IgE Levels in Young Children With Atopic Dermatitis Poster #64623 e-Poster Bissonnette Dupilumab Treatment Improves Skin Barrier Function in Adolescent and Adult Patients With Atopic Dermatitis: Results from the BALISTAD and BALISTAD-CN Studies Poster #63413 e-Poster Goleva Dupilumab Normalizes Filaggrin Processing and Improves Clinical Outcomes in Children With Moderate-to-Severe Atopic Dermatitis Poster #61982 e-Poster Irvine Growth Analysis in Children Aged 6 to 11 Years with Severe Atopic Dermatitis and Impact of up to 52 Weeks of Dupilumab Treatment on Height Oral Presentation #62057 March 7, 2025 4:40 p.m. – 4:45 p.m. ET Paller Dupilumab Safety and Efficacy Up To 3 Years in Children Aged 6 Months to 11 Years With Atopic Dermatitis Poster #62960 e-Poster Paller Baseline Growth Analysis of Children and Adolescents With Moderate-to-Severe Atopic Dermatitis Enrolled in Phase 3 Dupilumab Trials Oral Presentation #62286 March 7, 2025 10:00 a.m. – 10:05 a.m. ET Ramien Dupilumab Improves Patient-Reported Outcomes in Patients of Color Aged Less Than 12 Years With Atopic Dermatitis: 4-Year Results from the PEDISTAD Registry Poster #64507 e-Poster Simpson Real-World Effectiveness of Dupilumab in African American Patients With Atopic Dermatitis: 3-Year Data from the PROSE Registry Poster # 64411 e-Poster Ständer Dupilumab Treatment Corrects Upregulation of Type 2 Cytokines Cascades and Improves Pruritus Symptoms in Patients With Moderate-to-Severe Atopic Dermatitis Poster #63364 e-Poster Tada Effectiveness and Safety Data of Dupilumab in Asian Adult Patients With Atopic Dermatitis are Consistent With the Overall Global Population: Real-World Insights 2 Years into the GLOBOSTAD Multinational Prospective Observational Study Poster #63294 e-Poster Wang Dupilumab Improves Health-Related Quality of Life and Work Productivity Among Adults With Moderate-to-Severe Atopic Dermatitis in Clinical Practice: 5-Year Follow-up Results From the RELIEVE-AD Study Poster # 63592 e-Poster Wang Sustained Disease Control Among Adults With Moderate-to-Severe Atopic Dermatitis in Clinical Practice: 5-Year Follow-up Results From the RELIEVE-AD Study Oral Presentation #63519 March 8, 2025 10:00 a.m. – 10:05 a.m. ET Wine Lee Real-World Treatment Outcomes of Systemic Treatments for Moderate-to- Severe Atopic Dermatitis in Children Aged Less Than 12 Years from Racial Minority Groups: 4-Year Results from the PEDISTAD Registry Poster #64468 e-Poster Chovatiya Design and Rationale of ARMADA-AD Disease Registry: An International, Prospective, Observational Registry to Characterize Unmet Needs and Evaluate Real-World Effectiveness and Safety of Systemic Therapies in Adults and Adolescents With Atopic Dermatitis Poster #60502 e-Poster Geng Amlitelimab Reduces Th2-, Th1-, and Th17/22-Related Cytokines and Chemokines in Adults With Moderate-to-Severe Atopic Dermatitis): Results From an Exploratory Analysis of the Phase 2b STREAM-AD Study Poster #62188 e-Poster Kim Impact of amlitelimab (an anti-OX40 Ligand antibody) on Maintenance of Itch Response in Atopic Dermatitis: Results from the 52-Week STREAM-AD Phase 2b Study Poster #62198 e-Poster Thaci Interim Results of RIVER-AD: 28-Week Open-Label Safety and Efficacy of amlitelimab in Patients With Atopic Dermatitis Not Initially Achieving Clinical Response at Week 24 of the STREAM-AD Phase 2b Trial Poster #63598 e-Poster Bullous pemphigoid TBC Efficacy and Safety of Dupilumab in Patients With Bullous Pemphigoid: Results from LIBERTY-BP ADEPT Phase 2/3 Study Late Breaking Oral Presentation #66987 March 8, 2025 Time TBC Chronic spontaneous urticaria Friedman Persistence and Adherence Among Patients With Chronic Spontaneous Urticaria Initiating Advanced Therapies: A Real-World, Claims Database Study Poster #64349 e-Poster Prurigo nodularis Elmariah Real-World Prevalence of Psychiatric and Sleep Disorders Among Adult Patients With Prurigo Nodularis and Prurigo Nodularis Patients Initiating Dupilumab in the US Poster #63307 e-Poster Kim Real-World Prevalence of Comorbidities Among Adult Patients With Prurigo Nodularis With and Without Type 2 Inflammatory Diseases in the US Poster #63337 e-Poster Kwatra Real-World Comorbidities of Adult Patients With Prurigo Nodularis Initiating Dupilumab in the US by Race/Ethnicity Poster #63345 e-Poster Mollanazar Real World Comorbidities of Adult Patients With Prurigo Nodularis Initiating Dupilumab in the US Oral Presentation #63281 March 7, 2025 11:40 a.m. - 11:45 a.m. ET Mollanazar Real-World Medication Use Prior to Dupilumab Initiation Among Adult Patients With Prurigo Nodularis in the US Poster #63298 e-Poster Thomas Dupilumab Improves Disease Control as Early as 1 Month among Adults With Prurigo Nodularis in Clinical Practice: Initial Results from the RELIEVE-PN Study Poster #64375 e-Poster Yosipovitch Real-World Comorbidities, Treatment Use, and Healthcare Resource Utilization Among Elderly Patients With Prurigo Nodularis Initiating Dupilumab in the US Oral Presentation #63341 March 8, 2025 1:05 p.m. - 1:10 p.m. ET About Dupixent Dupixent (dupilumab) is a fully human monoclonal antibody that inhibits the signaling of the IL4 and IL13 pathways and is not an immunosuppressant. The Dupixent development program has shown significant clinical benefit and a decrease in type-2 inflammation in phase 3 studies, establishing that IL4 and IL13 are two of the key and central drivers of type-2 inflammation that play a major role in multiple related and often co-morbid diseases. Dupixent has received regulatory approvals in more than 60 countries in one or more indications including certain patients with atopic dermatitis, asthma, chronic rhinosinusitis with nasal polyps, eosinophilic esophagitis, prurigo nodularis, chronic spontaneous urticaria, and chronic obstructive pulmonary disease in different age populations. More than 1,000,000 patients are currently being treated with Dupixent globally. Dupixent development program Dupilumab is being jointly developed by Sanofi and Regeneron under a global collaboration agreement. To date, dupilumab has been studied across more than 60 clinical studies involving more than 10,000 patients with various chronic diseases driven in part by type-2 inflammation. In addition to the currently approved indications, Sanofi and Regeneron are studying dupilumab in a broad range of diseases driven by type-2 inflammation or other allergic processes in phase 3 studies, including chronic pruritus of unknown origin, bullous pemphigoid, and lichen simplex chronicus. These potential uses of dupilumab are currently under clinical investigation, and the safety and efficacy in these conditions have not been fully evaluated by any regulatory authority. About amlitelimab Amlitelimab is a fully human, nondepleting, OX40-ligand (OX40L) monoclonal antibody that specifically blocks upstream OX40L signaling to potentially normalize T-cell mediated inflammation without T-cell depletion. It is being studied in a range of immune-mediated diseases and inflammatory disorders, including atopic dermatitis, hidradenitis suppurativa, alopecia areata, scleroderma, celiac disease and asthma. The potential uses of amlitelimab are currently under clinical investigation and its safety and efficacy have not been evaluated by any regulatory authority. About Sanofi We are an innovative global healthcare company, driven by one purpose: we chase the miracles of science to improve people’s lives. Our team, across the world, is dedicated to transforming the practice of medicine by working to turn the impossible into the possible. We provide potentially life-changing treatment options and life-saving vaccine protection to millions of people globally, while putting sustainability and social responsibility at the center of our ambitions. Sanofi is listed on EURONEXT: SAN and NASDAQ: SNY Media Relations Sandrine Guendoul | +33 6 25 09 14 25 | [email protected] Evan Berland | +1 215 432 0234 | [email protected] Nicolas Obrist | +33 6 77 21 27 55 | [email protected] Léo Le Bourhis | +33 6 75 06 43 81 | [email protected] Victor Rouault | +33 6 70 93 71 40 | [email protected] Timothy Gilbert | +1 516 521 2929 | [email protected] Investor Relations Thomas Kudsk Larsen |+44 7545 513 693 | [email protected] Alizé Kaisserian | +33 6 47 04 12 11 | [email protected] Felix Lauscher | +1 908 612 7239 | [email protected] Keita Browne | +1 781 249 1766 | [email protected] Nathalie Pham | +33 7 85 93 30 17 | [email protected] Tarik Elgoutni | +1 617 710 3587 | [email protected] Thibaud Châtelet | +33 6 80 80 89 90 | [email protected] Yun Li | +33 6 84 00 90 72 | yun.li3 @sanofi.com Sanofi Forward-Looking Statements This media update contains forward-looking statements as defined in the Private Securities Litigation Reform Act of 1995, as amended. 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