atezolizumab + alpelisib

Atezolizumab + alpelisib is an investigational combination therapy consisting of two distinct anticancer agents with complementary mechanisms of action. Atezolizumab is a monoclonal antibody immune checkpoint inhibitor targeting programmed death-ligand 1 (PD-L1), thereby enhancing T-cell mediated immune responses against tumor cells. Alpelisib is a small molecule inhibitor of the phosphatidylinositol 3-kinase catalytic subunit alpha isoform (PI3Kα), specifically inhibiting the PI3K pathway in cancer cells harboring PIK3CA mutations, which are associated with tumor growth and resistance to endocrine therapy. This combination has been explored in clinical research for advanced or metastatic breast cancer, particularly hormone receptor-positive, HER2-negative, PIK3CA-mutated subtypes[1][2][6].