The FDA on Friday approved alpelisib, the first PI3K inhibitor to treat postmenopausal women and men with hormone receptor-positive, HER2-negative, PIK3CA-mutated breast cancer that progressed during or after an endocrine-based regimen, according to an agency press release.

Alpelisib (Piqray, Novartis), used in combination with fulvestrant (Faslodex, AstraZeneca), was approved with a companion diagnostic test, therascreen PIK3CA RGQ PCR Kit (Qiagen), to detect the PIK3CA mutation in a tissue and/or a liquid biopsy. Patients who are negative by the therascreen test using the liquid biopsy should undergo tumor biopsy for PIK3CA mutation testing.