Rilzabrutinib

Sanofi’s Wayrilz approved in Japan to treat immune thrombocytopenia Wayrilz is a BTK inhibitor that works through multi-immune modulation to help address the underlying causes of immune thrombocytopenia (ITP) Approval based on the LUNA 3 phase 3 study that demonstrated rapid and durable platelet response and improvements in other symptoms ITP is a rare disease of complex immune dysregulation leading to lower platelet counts, bleeding, and reduced quality of life Paris, June 23, 2026. The Ministry of Health, Labour and Welfare in Japan has granted marketing and manufacturing authorization to Wayrilz (rilzabrutinib), a novel oral reversible Bruton’s tyrosine kinase inhibitor (BTKi), for the treatment of persistent or chronic immune thrombocytopenia (ITP) in patients who do not respond sufficiently to other treatments or in whom tolerability is considered to be problematic. Wayrilz can help address the underlying causes of the disease, through multi-immune modulation, targeting key pathways across the immune system. The approval is based on the LUNA 3 phase 3 study (clinical study identifier: NCT04562766) , in which Wayrilz met the primary and secondary endpoints, showing a positive impact on sustained platelet counts and other symptoms. "For ITP patients, achieving platelet counts close to normal and living without worrying about bleeding is extremely important. Additionally, in recent years, there has been growing interest in various other symptoms associated with ITP such as fatigue,” said Hisashi Kato , MD, PhD, Department of Blood Transfusion and Cell Therapy, The University of Osaka Hospital, Suita, Japan. “Wayrilz is a novel BTKi that works through multi-immune modulation to help address the root cause of ITP pathophysiology. It is expected to become a new therapeutic option that may help patients with disease management, including not only improvement in platelet counts but also considering patients' quality of life." “People living with immune thrombocytopenia who continue to experience symptoms, despite trying existing treatments, face a great unmet need,” said Manuela Buxo , Executive Vice President, Global Head of Specialty Care at Sanofi. “Wayrilz has a differentiated mechanism of action that enables multi-immune modulation to address the underlying pathophysiology of ITP and offers new hope to patients who have not responded to prior therapy. This milestone underscores Sanofi’s commitment to bringing innovative treatment options to rare disease patients around the world.” The LUNA 3 phase 3 study evaluated the efficacy and safety of Wayrilz compared to placebo in adults (n=202) with persistent or chronic ITP. Patients who achieved platelet count response at 12 weeks were eligible to continue the full 24-week double-blind period (64% of patients in the Wayrilz arm and 32% of patients in the placebo arm). Patients receiving Wayrilz experienced the following compared to patients receiving placebo: Statistically significant durable platelet response at week 25 (23% of patients in Wayrilz arm vs. 0% in placebo arm; p<0.0001) Faster time to first platelet response (36 days in Wayrilz arm vs. not reached in placebo arm; p<0.0001) Longer duration of platelet response (least square mean of 7 weeks in Wayrilz arm vs. 0.7 weeks in placebo arm) Patients receiving Wayrilz reported an overall 10.6-point improvement in the overall quality of life domain compared to a 2.3-point increase in the placebo arm, based on The Immune Thrombocytopenia Patient Assessment Questionnaire, a clinical tool designed to measure ITP symptoms and impacts. The results of this analysis are descriptive and were not powered for statistical significance. The most common adverse reactions (incidence ≥10%) were diarrhea, nausea, headache, abdominal pain, and COVID-19. Wayrilz is being studied across multiple other rare diseases, including IgG4-related disease (IgG4-RD), warm autoimmune hemolytic anemia (wAIHA), and sickle cell disease. These additional indications are currently under investigation and have not been approved by regulatory authorities. Japan has granted Wayrilz orphan drug designation for ITP, IgG4-RD, and wAIHA. About ITP ITP is a disease of complex immune dysregulation that causes low platelet counts (<100,000/μL), resulting in a variety of bleeding symptoms and high risk of thromboembolism. Beyond bruising and bleeding, which can include potentially life-threatening episodes like intracranial hemorrhage, people living with ITP may experience reduced quality of life, including physical fatigue and cognitive impairment. About Wayrilz Wayrilz (rilzabrutinib) is a novel oral reversible covalent BTK inhibitor that has the potential to be an effective new medicine for several rare immune-mediated or inflammatory diseases by working to restore immune balance via multi-immune modulation. The enzyme BTK, expressed in B cells, macrophages, and other innate immune cells, plays a critical role in multiple immune-mediated disease processes and inflammatory pathways. With the application of the TAILORED COVALENCY ® technology, Wayrilz can selectively inhibit the BTK target. Wayrilz is now approved for the treatment of ITP in the US, the EU, the UAE, the UK and Japan. About Sanofi Sanofi is an R&D driven, AI-powered biopharma company committed to improving people’s lives and delivering compelling growth. We apply our deep understanding of the immune system to invent medicines and vaccines that treat and protect millions of people around the world, with an innovative pipeline that could benefit millions more. Our team is guided by one purpose: we chase the miracles of science to improve people’s lives; this inspires us to drive progress and deliver positive impact for our people and the communities we serve, by addressing the most urgent healthcare, environmental, and societal challenges of our time. Sanofi is listed on EURONEXT: SAN and NASDAQ: SNY Media Relations Sandrine Guendoul | +33 6 25 09 14 25 | sandrine.guendoul@sanofi.com Evan Berland | +1 215 432 0234 | evan.berland@sanofi.com Léo Le Bourhis | +33 6 75 06 43 81 | leo.lebourhis@sanofi.com Victor Rouault | +1 617 356 4751 | victor.rouault@sanofi.com Timothy Gilbert | +1 516 521 2929 | timothy.gilbert@sanofi.com Léa Ubaldi | +33 6 30 19 66 46 | lea.ubaldi@sanofi.com Ekaterina Pesheva | +1 410 926 6780 | ekaterina.pesheva@sanofi.com Laura Romby | +33 6 74 16 74 29 | laura.romby@sanofi.com Investor Relations Thomas Kudsk Larsen |+44 7545 513 693 | thomas.larsen@sanofi.com Alizé Kaisserian | +33 6 47 04 12 11 | alize.kaisserian@sanofi.com Keita Browne | +1 781 249 1766 | keita.browne@sanofi.com Nathalie Pham | +33 7 85 93 30 17 | nathalie.pham@sanofi.com Nina Goworek | +1 908 569 7086 | nina.goworek@sanofi.com Thibaud Châtelet | +33 6 80 80 89 90 | thibaud.chatelet@sanofi.com Yun Li | +33 6 84 00 90 72 | yun.li3@sanofi.com Sanofi Forward-Looking Statements This press release contains forward-looking statements within the meaning of applicable securities laws, including the Private Securities Litigation Reform Act of 1995, as amended. 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Ethyreal will share more information on its asset at the Endocrine Society’s 2026 Annual Meeting. \n Ethyreal Bio has exited stealth with $101 million in funding, joining the queue of companies preparing to challenge Amgen’s Tepezza.Backed by series A and B round investors, including Atlas Venture and Medicxi Ventures, the Massachusetts-based biotech has quietly advanced an anti-TSHR antibody to the cusp of clinical development. A first-in-human trial of the asset, dubbed ETHY-001, is scheduled to start this year. Ethyreal is developing the drug candidate for thyroid eye disease (TED) and Graves’ disease (GD).“These two conditions frequently coexist in the same individual, yet current treatments for GD do not treat or prevent TED, and conversely, TED treatments do not address the hyperthyroidism characteristic of GD,” Ethyreal CEO Niranjan Kameswaran, Ph.D., said in a statement.Amgen markets Tepezza in TED. With an FDA approval decision due this month, Viridian Therapeutics is at the front of a pack of companies aiming to compete with Amgen’s blockbuster. Tepezza and Viridian’s veligrotug both target IGF-1R. The GD pipeline includes argenx’s efgartigimod, Biohaven Therapeutics’ BHV-1300, Immunovant Sciences’ IMVT-1402 and Sanofi’s rilzabrutinib. Ethyreal has identified TSHR blockade as a way to treat TED and GD. By stopping autoantibodies from activating the receptor, the biotech aims to treat TED symptoms in the eye while tackling GD by reducing excess thyroid hormone production in thyroid cells.Other companies are pursuing similar approaches. Changchun GeneScience Pharmaceutical advanced an anti-TSHR antibody into the clinic and sold ex-China rights to the candidate to Yarrow Bioscience for $70 million upfront. Ollin Biosciences also entered the space by partnering with a Chinese biotech, agreeing to a financial package worth up to $440 million for rights to VelaVigo Bio’s TSHRxIGF-1R bispecific.  The TSHR race includes oral antagonists. Crinetics Pharmaceuticals and Septerna have shared preclinical data on “nonpeptide” and small molecule TSHR antagonists, respectively, in recent years, although both biotechs are focused on other programs.Ethyreal will share more information on its contender next week at the Endocrine Society’s 2026 Annual Meeting. The presentation will cover preclinical data on an anti-TSHR antibody with half-life extension technology that is designed for subcutaneous administration using an autoinjector. Ethyreal has taken the asset toward the clinic using the proceeds of previously undisclosed series A and B rounds.