PRN3562

PRN3562 is a small molecule inhibitor of Bruton's tyrosine kinase (BTK) originally developed by Principia Biopharma using its proprietary Tailored Covalency platform. Designed as a potent and selective reversible inhibitor, PRN3562 was intended to treat various autoimmune and inflammatory diseases by modulating B-cell receptor signaling and myeloid cell activation. Following Sanofi's acquisition of Principia Biopharma in 2020, the development of PRN3562 appears to have been deprioritized in favor of other BTK inhibitors in the portfolio, such as rilzabrutinib and tolebrutinib. The drug's reversible binding profile was intended to offer a distinct safety and pharmacodynamic profile compared to irreversible BTK inhibitors.