Ensem Therapeutics Inc. has gained IND clearance from the FDA for ETX-636, a novel allosteric pan-mutant-selective PI3Kα inhibitor and degrader. A first-in-human trial will begin this quarter. The phase I/II study will evaluate ETX-636 administered alone and in combination with fulvestrant in participants with advanced solid tumors, including breast cancer, harboring a PI3Kα mutation.