Alpelisib (Piqray) is a PI3Kα-specific inhibitor, approved by the FDA in May 2019 for use in combination with endocrine therapy fulvestrant for the treatment of hormone receptor (HR)-positive, HER2-negative, PIK3CA-mutated, advanced, or metastatic breast cancer (https://www.fda.gov/news-events/press-announcements/fda-approves-first-pi3k-inhibitor-breast-cancer; 24 May 2019). Here, ERBB2 is linked to breast cancer.