Media Update: Sanofi presents new data from robust MS clinical pipeline exploring multiple approaches to address important unmet patient needs

Sanofi presents new data from robust MS clinical pipeline exploring multiple approaches to address important unmet patient needs

Paris, October 2, 2023. Sanofi will present new data at the 9th Joint ECTRIMS-ACTRIMS meeting evaluating three investigational treatments for multiple sclerosis (MS) that target the underlying biology of MS to treat the full spectrum of disease and reinforce the commitment to address smoldering neuroinflammation, a key driver of disability progression.

New findings from brain-penetrant and bioactive tolebrutinib, the company’s potentially best-in-disease oral investigational Bruton’s tyrosine kinase (BTK) inhibitor, reinforce the ability of this near-term candidate to reach the central nervous system (CNS) to target smoldering neuroinflammation at its source. Data from frexalimab, the potentially best-in-disease novel second-generation investigational anti-CD40L antibody, and SAR443820, the first-in-class oral investigational brain-penetrant receptor-interacting protein kinase 1 (RIPK1) inhibitor, will also be presented.

Global Head of Neurology Development, Sanofi

Our deep expertise in neuroimmunology has allowed us to explore distinct mechanisms that have the potential to halt this debilitating disease by directly crossing the blood-brain barrier or indirectly inhibiting the upstream immunological processes. Specifically for tolebrutinib, addressing the smoldering neuroinflammation activity within the CNS represents a great unmet need in MS and offers significant potential for limiting the destructive, disabling nature of this disease.

Abstracts accepted for presentation include:

| Tolebrutinib(BTKi) | Safety and Clinical Efficacy Outcomes from the Long-term Extension Study of Tolebrutinib in Participants with Relapsing Multiple Sclerosis: 3-Year Results| Poster: #P278Oct. 11, 16.30-18.30 CEST |

| | Bruton’s Tyrosine Kinase Regulates Microglial Proinflammatory Pathways – Implications For Multiple Sclerosis| Poster: #P134Oct. 11, 16.30-18.30 CEST |

| | Cerebrospinal Fluid Myeloid Modulation In Patients With Multiple Sclerosis Treated With Tolebrutinib | Oral Platform Presentation#1599

Oct. 12, 10:35-10:45 CEST |

| | Tolebrutinib Can Reverse a Multiple Sclerosis-Induced Cerebrospinal Fluid Proteomic Alteration | Poster: #P645Oct. 12, 17:00–19.00 CEST |

| | MRI Outcomes From The Long-Term Extension Study Of Tolebrutinib in Participants With Relapsing Multiple Sclerosis: 3-Year Results| Poster: #P684Oct. 12, 17.00–19.00 CEST |

| | Baseline Characteristics in the Tolebrutinib Phase 3 Non-Relapsing Secondary Progressive Multiple Sclerosis (nrSPMS) HERCULES Clinical Trial| Poster: #P1476ePoster |

| Frexalimab(anti-CD40L) | Phase 2 Efficacy and Safety of Frexalimab: 6 Month Results of a Novel CD40L Inhibitor in Relapsing Multiple Sclerosis| Poster: #P275Oct. 11, 16.30-18.30 CEST |

| | Inhibition Of CD40L With Frexalimab Blunts Innate Immune Responses To ActivatedT Cells | Poster: #P1279ePoster |

| SAR443820 (RIPK1i) | RIPK1 Activation Mediates Disease Progression In Multiple Sclerosis By Driving Neuroinflammatory Signaling In Microglia And Astrocytes| Poster: #P156Oct. 11, 16.30–18.30 CEST |

| Disease State | Patterns and Predictors of Conversion from Relapsing-Remitting to Secondary Progressive MS: A Longitudinal Study Using the Danish Multiple Sclerosis Registry| Poster: #042Oct. 11, 16.30–18.30 CEST |

| An International Consensus with Delphi Methodology on Smoldering Disease in MS: Definition, Clinical Manifestations and Underlying Biology| Poster: #P437Oct. 12, 17.00–19.00 CEST | |

| Digital Biomarkers For Early Detection Of Disability Worsening In MS: The MS-DETECT Study Design | Poster: #P1449ePoster | |

Tolebrutinib is a potentially best-in-disease oral investigational brain-penetrant and bioactive Bruton’s tyrosine kinase (BTK) inhibitor that achieves CSF concentrations predicted to modulate B lymphocytes and microglial cells. Tolebrutinib is being evaluated in Phase 3 clinical trials for the treatment of relapsing forms of MS (RMS), non-relapsing secondary progressive MS (nrSPMS), and primary progressive MS (PPMS) and its safety and efficacy have not been evaluated by any regulatory authority worldwide. For more information on tolebrutinib clinical trials, please visit www.clinicaltrials.gov.

Frexalimab (SAR441344) is a potentially best-in-disease second generation investigational anti-CD40L antibody that blocks the costimulatory CD40/CD40L pathway which is important for activation and function of adaptive (T and B cells) and innate (macrophages/microglia and dendritic cells) immunity. Through this unique upstream mechanism of action, frexalimab has the potential to address both acute and chronic neuroinflammation in MS. Sanofi is developing SAR441344 under an exclusive license from ImmuNext Inc. Frexalimab is being evaluated in Phase 2 clinical trials for Sjogren’s Syndrome, Systemic Lupus Erythematosus and Multiple Sclerosis, and its safety and efficacy have not been reviewed by any regulatory authority. For more information on frexalimab clinical trials, please visit www.clinicaltrials.gov.

SAR4433820 is an oral, first-in-class brain-penetrant RIPK1 inhibitor that targets inflammatory cell signalling and activation of cell death pathways in MS pathophysiology. Its multitargeted mechanism of action and flexibility to be used as a monotherapy or in combination gives SAR443820 the potential to address neurodegeneration and disability accumulation​. SAR443820 is being evaluated in Phase 2 clinical trials for Amyotrophis Lateral Sclerosis and Multiple Sclerosis, and its safety and efficacy have not been reviewed by any regulatory authority. SAR443820 is in-licensed from Denali. For more information on SAR443820 clinical trials, please visit www.clinicaltrials.gov.

For nearly two decades, we have channeled our energy into improving the lives of people with relapsing forms of MS, delivering disease-modifying therapies with distinct mechanisms of action and partnering with the MS community. We are dedicated to using our scientific and clinical heritage in MS to develop therapeutic solutions that address other neuroinflammatory, neurodegenerative, and genetic diseases.

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 some 100 countries, 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

Sally Bain | + 1 617 834 6026 | [email protected]

Victor Rouault | + 33 6 70 93 71 40 | [email protected]

Eva Schaefer-Jansen | + 33 7 86 80 56 39 | [email protected]

Arnaud Delépine | + 33 6 73 69 36 93 | [email protected]

Corentine Driancourt | + 33 6 40 56 92 21 | [email protected]

Felix Lauscher | + 1 908 612 7239 | [email protected]

Tarik Elgoutni| + 1 617 710 3587 | tarik.e [email protected]

Nathalie Pham | + 33 7 85 93 30 17 | [email protected]

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