Based on the phase III trial, SOLAR‐1,15PIK3CAm have reached level 2 evidence for predicting benefit, according to the Magnitude of Clinical Benefit Scale by ESMO, from fulvestrant combined with alpelisib, an alpha‐specific PI3K inhibitor in patients with advanced HR+/HER2− BC, who had previously progressed to a previous line of endocrine therapy, showing a significantly higher median PFS compared to placebo plus fulvestrant (HR = 0.65 [95% CI, 0.50–0.85], p < 0.001). The gene discussed is PIK3CA; the disease is breast cancer.