Paris, February 24, 2024. Positive results from the Phase 2 study RILECSU showed that rilzabrutinib significantly improved itch, hives and urticaria in adults with moderate-to-severe chronic spontaneous urticaria (CSU), whose symptoms are not adequately controlled by H1 antihistamines. These results were presented today in a late-breaking poster at the 2024 American Academy of Allergy, Asthma and Immunology (AAAAI) Annual Meeting in Washington, DC and form the basis for the Phase 3 program which is on track to start in 2024.

Professor Marcus Maurer, M.D.
Professor of Dermatology and Allergy, Executive Director of the Institute of Allergology at the Charité Berlin
“People with CSU are living with debilitating symptoms such as intensely itchy recurrent hives, swelling, or both which can have a high impact on their day-to-day lives. These data are promising news for patients that cannot be controlled with standard-of-care antihistamines – the possibility of controlling itch rapidly with an oral medicine would offer an important advancement in the treatment of this disease.”

Naimish Patel, M.D.
Head of Global Development, Immunology and Inflammation, Sanofi
“These data reinforce the potential of rilzabrutinib as a treatment option for patients with moderate-to-severe CSU and we believe that the rapid improvement of itch could make a meaningful difference in alleviating the physical and psychosocial burden these patients suffer from. Based on these data, later this year we will advance rilzabrutinib into Phase 3 development in both CSU and prurigo nodularis, another skin disorder characterized by relentless itching. We also look forward to data readouts for rilzabrutinib in 2024 with the opportunity to further demonstrate its potential impact across multiple immune-mediated diseases.”

Key Results 
In this dose-ranging study, different doses of rilzabrutinib were evaluated: 400 mg once every evening (QPM), 400 mg twice a day (BID), 400 mg three times a day (TID).

In the intent-to-treat (ITT) population which included either patients who were previously naïve or incomplete responders to omalizumab, Rilzabrutinib 400 mg TID demonstrated:

• Significant reduction from baseline in weekly itch severity score (ISS7) at Week 12, a key symptom of the disease, [least squares mean (LSM) -9.58 vs -6.31, respectively; p=0.0181]. Significant changes in ISS7 were seen as early as Week 1.
• Significant reduction from baseline to week 12 in weekly urticaria activity score (UAS7) [LSM -17.95 vs -11.20, respectively; p=0.0116].
• Significant reduction from baseline to week 12 in weekly hives severity score (HSS7) [LSM -8.31 vs -4.89; p<0.0100].
   

Rilzabrutinib was generally well-tolerated with no events of cytopenia, bleeding or atrial fibrillation seen with other BTK inhibitor. Treatment-emergent AEs occurring at a higher frequency with rilzabrutinib vs placebo were diarrhea (29.3% TID and BID, 7.9% QPM, 15% placebo), nausea (19.5% TID, 17.1% BID, 13.2% QPM, 5.0% placebo), headache (9.8% TID, 14.6% BID, 5.3% QPM, 0.0% placebo) and abdominal pain (0.0% TID, 12.2% BID, 2.6% QPM, 5.0% placebo).

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

About CSU
CSU is an inflammatory skin condition driven mainly by the activation of cutaneous mast cells, which causes itchy recurrent hives, swelling, or both. CSU is typically treated with H1 antihistamines and biologics; however, the disease remains uncontrolled in up to 50% of patients, who are left with limited alternative treatment options. These individuals continue to experience debilitating symptoms that can significantly impact quality of life.

About the RILECSU study
RILECSU is a 52-week Phase 2 study, comprising a 12-week randomized, double-blind, placebo-controlled, dose-ranging, efficacy and safety period, followed by a 40-week open-label extension period.

RILECSU is evaluating rilzabrutinib in adult patients with moderate-to-severe CSU who remain symptomatic despite use of H1 antihistamine treatment and are either naïve to or incomplete responders to omalizumab. The primary endpoint was change from baseline in weekly itch severity score ISS7 at 12 weeks. Secondary endpoints include change from baseline in weekly UAS7 at 12 weeks and change from baseline weekly HSS7 at 12 weeks.

Participants in the trial (n=160) were randomized 1:1:1:1 to rilzabrutinib 400mg once every evening (QPM), 400mg twice a day (BID), 400mg three times a day (TID), or matching placebo.

About Rilzabrutinib
Rilzabrutinib is an oral, reversible, covalent BTK inhibitor that has the potential to be a first- or best-in-class treatment of a number of immune-mediated diseases. BTK, expressed in B cells and mast cells, plays a critical role in multiple immune-mediated disease processes. With the application of Sanofi’s TAILORED COVALENCY^® technology, rilzabrutinib can selectively inhibit the BTK target while potentially reducing the risk of off-target side effects.

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 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

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

Investor Relations
Eva Schaefer-Jansen | + 33 7 86 80 56 39 | eva.schaefer-jansen@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.

Source:- Globenewswire