Sanofi-Aventis Groupe announced promising results from its Phase 2 RILECSU study, showcasing rilzabrutinib's ability to significantly reduce itch severity and improve disease activity in adults with moderate-to-severe chronic spontaneous urticaria (CSU). The findings were unveiled in a late-breaking poster session at the 2024 American Academy of Allergy, Asthma & Immunology (AAAAI) Annual Meeting in Washington, DC.

Rilzabrutinib, an innovative oral Bruton's tyrosine kinase (BTK) inhibitor, demonstrated a rapid reduction in weekly itch severity score (ISS7) starting from the first week of treatment. These results lay the groundwork for Phase 3 trials in CSU and prurigo nodularis slated to commence later this year.

Key Findings from the RILECSU Study:

• Significant decrease in ISS7 at Week 12, with the highest dose (400 mg three times a day) showing a notable reduction compared to placebo.
• Early and significant reductions in weekly urticaria activity score (UAS7) and weekly hives severity score (HSS7) by Week 12.
• Rilzabrutinib was generally well-tolerated, with the most common adverse events being diarrhea, nausea, and headache, showing a favorable safety profile without the severe side effects associated with other BTK inhibitors.

Expert Insights:

Professor Marcus Maurer, a renowned expert in dermatology and allergy, highlighted the transformative potential of rilzabrutinib for patients inadequately controlled by standard antihistamines. The prospect of rapidly controlling itch with an oral medication could significantly enhance the quality of life for those suffering from CSU.

Dr. Naimish Patel, Head of Global Development for Immunology and Inflammation at Sanofi, expressed optimism regarding rilzabrutinib's future in addressing the needs of patients with moderate-to-severe CSU. The rapid alleviation of itch and disease symptoms could mark a significant leap forward in treating this and other immune-mediated diseases.

Looking Ahead:

With rilzabrutinib positioned as one of the 12 potential blockbusters in Sanofi’s immunology pipeline, the focus is now on advancing to Phase 3 trials. The upcoming pivotal Phase 3 readout in immune thrombocytopenia and Phase 2 results in asthma, IgG4-related disease, and warm autoimmune hemolytic anemia in 2024 are keenly anticipated, promising to further establish rilzabrutinib's role in the treatment landscape of immune-mediated diseases.

Rilzabrutinib's journey through clinical trials underscores Sanofi's commitment to pioneering treatments that address unmet medical needs, with the potential to significantly improve the lives of patients around the globe.