Emerging therapy targeting tyrosine-protein kinase BTK: potential for ibrutinib and other BTK inhibitors

Tyrosine-protein kinase BTK (Bruton tyrosine kinase) plays a critical role in the B cell receptor signaling pathway, and as such, mediates many immune responses. Recent studies targeting BTK with small-molecule inhibitors have shown these agents to be effective with relatively low systemic toxicity. BTK inhibitors, such as ibrutinib, CC-292 (AVL-292), ONO-4059 and HM-71224,, are proving to be impressively effective for treating B cell malignancies such as chronic myeloid leukemia and lymphomas. Other diseases that may be treatable with BTK inhibitors include multiple myeloma, as well as autoimmune conditions such as rheumatoid arthritis and lupus. Here, we describe the function of BTK and the potential of the new breed of BTK inhibitors for the clinical treatment of BTK-dependent conditions.