Discovery of Branebrutinib (BMS-986195): A Strategy for Identifying a Highly Potent and Selective Covalent Inhibitor Providing Rapid in Vivo Inactivation of Bruton’s Tyrosine Kinase (BTK)

Bruton’s
tyrosine kinase (BTK), a non-receptor tyrosine
kinase, is a member of the Tec family of kinases and is essential
for B cell receptor (BCR) mediated signaling. BTK also plays a critical
role in the downstream signaling pathways for the Fcγ receptor
in monocytes, the Fcε receptor in granulocytes, and the RANK
receptor in osteoclasts. As a result, pharmacological inhibition of
BTK is anticipated to provide an effective strategy for the clinical
treatment of autoimmune diseases such as rheumatoid arthritis and
lupus. This article will outline the evolution of our strategy to
identify a covalent, irreversible inhibitor of BTK that has the intrinsic
potency, selectivity, and pharmacokinetic properties necessary to
provide a rapid rate of inactivation systemically following a very
low dose. With excellent in vivo efficacy and a very desirable tolerability
profile, 5a (branebrutinib, BMS-986195) has advanced
into clinical studies.