By Fineline Cube 
French pharmaceutical major Sanofi (NASDAQ: SNY) announced that it has received another orphan drug designation (ODD) from the European Medicines Agency (EMA) for its rilzabrutinib, a reversible covalent Bruton’s tyrosine kinase (BTK) inhibitor, for the treatment of IgG4-related disease (IgG4-RD). This designation underscores the potential of rilzabrutinib to address a significant unmet medical need in this rare condition.
Background on Rilzabrutinib
Rilzabrutinib has already received orphan designations for immune thrombocytopenia (ITP) in the US, EU, and Japan, as well as for warm autoimmune hemolytic anemia, IgG4-RD, and sickle cell disease in the US. The drug has also been granted Fast Track designation in the US for ITP and IgG4-RD. Currently, rilzabrutinib is under regulatory review in the US, EU, and China for its potential use in ITP, with a target action date for the US FDA regulatory decision set for August 29, 2025.
Clinical Evidence
The orphan drug designation for IgG4-RD is supported by a Phase 2 study (NCT04520451). In this study, rilzabrutinib demonstrated a reduction in disease flare, other disease markers, and glucocorticoid sparing in patients with IgG4-RD after 52 weeks of treatment. The safety profile of rilzabrutinib was consistent with previous studies, with no new safety signals observed.-Fineline Info & Tech