The SOLAR-1 results led the FDA to approve “alpelisib in combination with fulvestrant for post-menopausal women, and men, with HR+/HER2− PIK3CA-mutated advanced or metastatic BC following progression on or after an endocrine-based regimen”, whereas the EMA approved alpelisib in a similar population but only “after an hormone treatment used alone has failed”. This evidence concerns the gene ERBB2 and breast cancer.