Study of TYK-00540 Tablets in Patients With Advanced Solid Tumors

This is an open-label, multi-center, dose-escalation and expansion phase I/II study to evaluate dose limiting toxicities (DLT) and determine the maximum tolerated dose (MTD) in subjects with locally advanced or metastatic solid tumors. To investigate the pharmacokinetic profile of TYK-00540 and its metabolites after single then multiple doses of TYK-00540 administered orally once daily. To assess preliminary effectiveness. To evaluate the efficacy of TYK-00540 combined with fulvestrant in subjects with ER+/HER2- breast cancer who have relapsed or progressed after treatment with CDK4/6 inhibitors