molecules of the month

Context. PRN1008 (rilzabrutinib, Sanofi) is an oral, reversible covalent Bruton’s tyrosine kinase (BTK) inhibitor in a Ph. III trial for immune thrombocytopenia. A simultaneously published inhibitor, PRN473, is in development as a topical treatment for atopic dermatitis. Following target discovery in 1993, and subsequent approval of the first BTK inhibitor 20 years later, research on these agents have intensified over the last decade, with numerous compounds currently either being marketed or in clinical trials for both oncology and immunology indications (e.g. ibrutinib, acalabrutinib, zanubrutinib). At the moment, there are no approved reversible BTK inhibitors, though non-covalent fenebrutinib (NCT05119569) is in late development for multiple sclerosis. Next-generation BTK inhibitors have focused on improving safety, as ibrutinib can lead to the development…