This is a Phase 1, open-label, multicenter, dose escalation and dose expansion study to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics, and antitumor activity of PF-07224826, as a single agent or in combination with endocrine therapy in participants with advanced solid tumors. This study will be divided into dose escalation/finding (Part 1) and dose expansion (Part 2).
In Part 1, participants with locally recurrent/advanced or metastatic Triple Negative Breast Cancer (TNBC), platinum resistant ovarian cancer and other advanced solid tumors will receive PF-07224826 as a single agent. Participants with HR-positive HER2-negative advanced or mBC will receive PF-07224826 in combination with endocrine therapy.
In Part 2 (Arm A), PF-07224826 will be evaluated in combination with fulvestrant in HR-positive HER2-negative advanced or mBC participants who have received prior CDK4/6 inhibitor. In Part 2 (Arm B), PF-07224826 will be evaluated in combination with fulvestrant in HR-positive HER2-negative locally advanced or mBC participants whose disease has progressed on prior endocrine therapy and is naïve to CDK4/6 inhibitors.