molecules of the month

5.      The Biogen reversible BTK kinase inhibitor, BIIB091, is a highly selective, phase I clinical candidate for multiple sclerosis. Irreversible BTK inhibitors have been explored and developed extensively, primarily in cancer. Reversible molecules have been less common, with the most clinically advanced molecule being fenebrutinib (phase III). This molecule possesses an uncommon benzoazepine core and triazine amide, whose polarity contribute to favorable overall drug properties. The amine is rendered non-basic by the oxetane and other substitutions (pKa = 2.8), and the molecule is more polar than the typical active-site kinase inhibitor with corresponding properties (e.g. solubility >50 ug/mL, logD = 2.2, PPB fu = 18%) The Biogen team reported good safety in two preclinical species with a high NOAEL of 250 mg/kg in…