molecules of the month

Context. DS69910557 (Daiichi Sankyo) is an oral inhibitor of parathyroid hormone (PTH) type 1 receptor (PTHR1) being developed as a calcium-lowering drug. The well-characterized secretin class receptor PTH1R is a principal regulator of bone remodeling and calcium ion homeostasis which makes it an attractive target for some endocrinopathies and bone disorders. The first report of a PTH receptor inhibitor, BIM-44002, which showed preclinical efficacy, was in 1997, although the compound did not demonstrate calcium-lowering activity in human studies. Since then, at least three other small molecule PTH1R antagonists have been reported, including a 1,3,4-benzotriazepine-based lead, SW106, and DS08210767, as well as the peptide antagonist DPC-AJ1951. Additionally, at least three small molecule agonists of the receptor have been reported, including AH-3960,…