Primary Progression-Free Survival Results From CAPItello-291

Erica L. Mayer, MD, MPH, of Dana-Farber Cancer Institute, recaps the primary analysis of CAPItello-291 in hormone receptor positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer, in which capivasertib plus fulvestrant improved progression-free survival from 3.1 to 7.3 months (hazard ratio, 0.50) in the PIK3CA/AKT1/PTEN-altered population and from 3.6 to 7.2 months (hazard ratio, 0.60) overall, with benefit regardless of ESR1 alteration or prior cyclin-dependent kinase (CDK) 4/6 inhibitor exposure, findings that supported the original approval. Sarah L. Sammons, MD, of the University of Maryland Greenebaum Comprehensive Cancer Center, argues that cross-trial comparison is unavoidable as the field crowds, positions alpelisib as the current comparator for PIK3CA-mutated disease, and views the capivasertib adverse event profile as more favorable. She adds that roughly 60% of enrolled patients had prior CDK4/6 inhibitor therapy and that subgroup data help guide choices for patients with co-occurring ESR1 and PIK3CA alterations.