Bruton's tyrosine kinase as a drug discovery target.

Bruton's tyrosine kinase (Btk) is an important mediator in multiple signal transduction pathways. Fifteen years of research have revealed a complex role for Btk in hematopoietic cells. These studies suggest that Btk may be a promising target for therapeutic intervention for several complicated diseases. Inhibitors targeting the Btk kinase domain have been developed and show clear beneficial effects in animal models of rheumatoid arthritis, lymphoma and other diseases. Here, an overview of these studies is presented with an emphasis on results stemming from medicinal chemistry research.