Positive results from the LUNA 3 phase 3 study demonstrated that rilzabrutinib 400 mg twice daily orally achieved the primary endpoint of durable platelet response in adult patients with persistent or chronic immune thrombocytopenia (ITP). The safety profile of rilzabrutinib was consistent with that reported in previous studies.
LUNA 3 study met its primary endpoint demonstrating a significantly higher proportion of patients receiving rilzabrutinib achieved the primary endpoint of durable platelet response versus placebo. This clinically and statistically significant result was achieved in a population of patients with primary ITP that had been refractory to prior therapy. Overall, study participants had a median of four prior ITP therapies and a median baseline platelet count of 15,000/μL (normal platelet count levels typically range from 150,000-450,000/μL). Positive results on key secondary endpoints also underscore the potential for rilzabrutinib to deliver clinically meaningful benefits for patients living with persistent and chronic ITP.

Rilzabrutinib was granted Fast Track Designation by the US Food and Drug Administration (FDA) for the treatment of ITP in November 2020 and was previously granted Orphan Drug Designation.

Houman Ashrafian
Executive Vice President, Head of Research and Development, Sanofi
“The results of this study reinforce rilzabrutinib’s potential to be a first-in-class oral, reversible BTK inhibitor that can provide clinically meaningful improvements for people living with severe immune-mediated diseases like ITP. These pivotal results are a testament to our commitment and expertise in rare blood diseases and ability to build a portfolio of next-generation small-molecule inhibitors that are both more selective and optimized to deliver robust efficacy and safety outcomes as compared to existing therapies.”

ITP is a serious, acquired autoimmune blood disorder characterized by autoantibody-mediated platelet destruction and impaired platelet production, leading to thrombocytopenia (low platelet counts of less than 100,000/μL) and an increased risk of life-threatening bleeding episodes (like intracranial hemorrhage). In addition, patients with ITP often experience significant quality-of-life impairments such as fatigue and cognitive dysfunction. With its dual mechanisms of action that reduce production of pathogenic autoantibodies and decrease macrophage mediated platelet destruction, rilzabrutinib could address the underlying mechanisms responsible for a wide range of ITP complications. 

About LUNA 3
LUNA 3 (NCT04562766) is a randomized, multicenter, phase 3 study evaluating the efficacy and safety of rilzabrutinib vs placebo in adult and adolescent patients with persistent or chronic ITP. Patients received either oral rilzabrutinib 400 mg twice a day or placebo through a 12- to 24-week double-blind treatment period, followed by a 28-week open-label treatment, and then a 4-week safety follow-up or long-term extension period. The adolescent part of the study is ongoing and still recruiting.

The primary endpoint is durable platelet response defined as the proportion of participants able to achieve platelet counts at or above 50,000/μL for for at least 8 out of the last 12 weeks of the 24-week blinded treatment period in the absence of rescue therapy. Secondary endpoints include the number of weeks with and time to platelet responses, rescue therapy use, and physical fatigue and bleeding score.

Detailed results of the LUNA 3 phase 3 study will be presented at a medical congress later this year.

Rilzabrutinib is currently under clinical investigation, and its safety and efficacy have not been evaluated by any regulatory authority.

About Rilzabrutinib
Rilzabrutinib is an oral, reversible, covalent BTK inhibitor that has the potential to be a first- or best-in-class treatment of several immune-mediated diseases. BTK, expressed in B cells, mast cells and other cells from the innate immune system, plays a critical role in inflammatory pathways and multiple immune-mediated disease processes. With the application of Sanofi’s TAILORED COVALENCY^® technology, rilzabrutinib can selectively inhibit the BTK target.

Rilzabrutinib is being studied across a variety of immune-mediated diseases, including immune thrombocytopenia (regulatory submission in H2 2024), asthma (phase 2), chronic spontaneous urticaria (phase 3 start in 2024), prurigo nodularis (phase 3 start in 2024), IgG4-related disease (phase 2b results in H2 2024), and warm autoimmune hemolytic anemia (phase 2b results in H2 2024).

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 | sandrine.guendoul@sanofi.com
Sally Bain | + 1 617 834 6026 | sally.bain@sanofi.com 
Victor Rouault | + 33 6 70 93 71 40 | victor.rouault@sanofi.com 
Timothy Gilbert | + 1 516 521 2929 | timothy.gilbert@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
Arnaud Delépine | + 33 6 73 69 36 93 | arnaud.delepine@sanofi.com
Corentine Driancourt | + 33 6 40 56 92 21 | corentine.driancourt@sanofi.com
Felix Lauscher | + 1 908 612 7239 | felix.lauscher@sanofi.com
Tarik Elgoutni| + 1 617 710 3587 | tarik.elgoutni@sanofi.com
Nathalie Pham | + 33 7 85 93 30 17 | nathalie.pham@sanofi.com

Sanofi Forward-Looking Statements
This press release contains forward-looking statements as defined in the Private Securities Litigation Reform Act of 1995, as amended. Forward-looking statements are statements that are not historical facts. These statements include projections and estimates and their underlying assumptions, statements regarding plans, objectives, intentions, and expectations with respect to future financial results, events, operations, services, product development and potential, and statements regarding future performance. Forward-looking statements are generally identified by the words “expects”, “anticipates”, “believes”, “intends”, “estimates”, “plans” and similar expressions. Although Sanofi’s management believes that the expectations reflected in such forward-looking statements are reasonable, investors are cautioned that forward-looking information and statements are subject to various risks and uncertainties, many of which are difficult to predict and generally beyond the control of Sanofi, that could cause actual results and developments to differ materially from those expressed in, or implied or projected by, the forward-looking information and statements. These risks and uncertainties include among other things, the uncertainties inherent in research and development, future clinical data and analysis, including post marketing, decisions by regulatory authorities, such as the FDA or the EMA, regarding whether and when to approve any drug, device or biological application that may be filed for any such product candidates as well as their decisions regarding labelling and other matters that could affect the availability or commercial potential of such product candidates, the fact that product candidates if approved may not be commercially successful, the future approval and commercial success of therapeutic alternatives, Sanofi’s ability to benefit from external growth opportunities, to complete related transactions and/or obtain regulatory clearances, risks associated with intellectual property and any related pending or future litigation and the ultimate outcome of such litigation, trends in exchange rates and prevailing interest rates, volatile economic and market conditions, cost containment initiatives and subsequent changes thereto, and the impact that pandemics or other global crises may have on us, our customers, suppliers, vendors, and other business partners, and the financial condition of any one of them, as well as on our employees and on the global economy as a whole. The risks and uncertainties also include the uncertainties discussed or identified in the public filings with the SEC and the AMF made by Sanofi, including those listed under “Risk Factors” and “Cautionary Statement Regarding Forward-Looking Statements” in Sanofi’s annual report on Form 20-F for the year ended December 31, 2023. Other than as required by applicable law, Sanofi does not undertake any obligation to update or revise any forward-looking information or statements.