Syros prioritizing oral CDK7, dropping IV after Phase I data

After tolerability issues in a Phase I trial led to lower doses and longer infusion times for its first clinical CDK7 inhibitor, Syros is choosing to concentrate instead on a preclinical oral compound aimed at the same target.

Syros Pharmaceuticals Inc. (NASDAQ:SYRS) intends to start next quarter a Phase I trial in select solid tumors of SY-5609, its non-covalent oral inhibitor of CDK7. The company believes that molecule is more selective and more potent than SY-1365, the IV treatment it has studied in Phase I testing, and offers more flexible dosing and convenience for patients...