Final Overall Survival in the PIK3CA/AKT1/PTEN-Altered Population

Erica L. Mayer, MD, MPH, of Dana-Farber Cancer Institute, presents the key secondary endpoint of overall survival in the PIK3CA/AKT1/PTEN-altered population of CAPItello-291, the phase 3 trial of capivasertib plus fulvestrant in hormone receptor positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. The Kaplan-Meier curves separate over the first 12 to 18 months before converging, and the hazard ratio of 0.83 did not reach significance (P = .201). Without crossover, post-progression therapy was imbalanced, with subsequent targeted therapy in about 43% of the fulvestrant-alone arm versus about 26% of the capivasertib arm. Seth A. Wander, MD, PhD, of Massachusetts General Hospital, says survival is hard to demonstrate in early lines given abundant subsequent options and that the result does not deter his enthusiasm. Sarah L. Sammons, MD, of the University of Maryland Greenebaum Comprehensive Cancer Center, remains comfortable today given the alternatives but notes competitive pressure ahead.