RecruitingPhase 1Drug trialClinical Trial of Avasopasem in Patients With Metastatic Hormone Receptor Positive Breast Cancer With Progression on a CDK 4/6 Inhibitor and Hormonal TherapyThis study aims to evaluate the safety of avasopasem in combination with CDK 4/6 inhibitor and hormonal therapy in women with metastatic hormone receptor positive breast cancer, and to see if the addition of avasopasem improves the effectiveness of a CDK 4/6 inhibitor and hormonal therapy.