Sanofi's Rilzabrutinib Receives Orphan Drug Designation in EU for IgG4-Related Disease

Sanofi's rilzabrutinib has received orphan drug designation in the EU for IgG4-related disease. The designation is based on positive phase 2 study data presented at the EULAR 2025 conference. Rilzabrutinib is a covalent and reversible BTK inhibitor with potential for treating rare autoimmune diseases. Sanofi is committed to developing new treatments for rare diseases.

Sanofi's rilzabrutinib has received orphan drug designation in the EU for IgG4-related disease (IgG4-RD). The designation, granted by the European Medicines Agency (EMA), underscores Sanofi's commitment to advancing new medicines for immune-mediated rare diseases. The decision was based on positive phase 2 study data presented at the European Alliance of Associations for Rheumatology (EULAR) 2025 Congress [1].

Rilzabrutinib, a reversible covalent Bruton’s tyrosine kinase (BTK) inhibitor, demonstrated effectiveness in reducing disease flare, other disease markers, and glucocorticoid sparing in IgG4-RD patients over a 52-week period. The safety profile of rilzabrutinib was consistent with previous studies, with no new safety signals observed [1].

The orphan drug designation is significant as it recognizes the potential of rilzabrutinib in addressing a rare, life-threatening condition affecting approximately eight out of 100,000 adult patients in the US each year. IgG4-RD is a progressive, relapsing, chronic immune-mediated rare disease that can lead to organ damage and irreversible dysfunction [1].

Sanofi has received orphan designations for rilzabrutinib in various conditions, including immune thrombocytopenia (ITP) and warm autoimmune hemolytic anemia in the US, the EU, and Japan. Additionally, rilzabrutinib has been granted fast track designation in the US for ITP and IgG4-RD [1].

The target action date for the US FDA regulatory decision for ITP, which was granted fast track designation, is August 29, 2025. Rilzabrutinib is currently under regulatory review in the US, the EU, and China for its potential use in ITP [1].

References:
[1] https://www.globenewswire.com/news-release/2025/08/14/3133146/0/en/Press-Release-Sanofi-s-rilzabrutinib-earns-orphan-designation-in-the-EU-for-IgG4-related-disease.html