This is a Phase IV, prospective, multicenter, open-label, non-comparative interventional study to assess the safety of alpelisib plus fulvestrant in men and post-menopausal women with HR-positive, HER2-negative, aBC with a PIK3CA mutation, whose disease has progressed on or after endocrine-based treatment.~Participants will be treated with alpelisib 300 mg orally once daily starting on Cycle 1 Day 1 in combination with fulvestrant (intramuscular injection) 500 mg on Cycle 1 Day 1 and Day 15, and Day 1 of every cycle thereafter in a 28 day cycle. Patients may be discontinued from treatment earlier due to unacceptable toxicity, disease progression, withdrawal of consent, or at the discretion of the investigator or the patient.
The purpose of this study is to determine the safety of alpelisib plus fulvestrant in men and post-menopausal women with HR-positive, HER2-negative, advanced or metastatic breast cancer (aBC) with a PIK3CA mutation, whose disease has progressed on or after endocrine-based treatment