Further to this exploratory data, the SANDPIPER study recruited 516 patients with endocrine-resistant, PIK3CA-mutant breast cancer to fulvestrant/taselisib vs. fulvestrant/placebo and met its primary endpoints of a statistically significant improvement in PFS (7.4 months vs. 5.4 months in favor of taselisib). The gene discussed is PIK3CA; the disease is breast cancer.