Pembrolizumab Plus Chemotherapy for HR+/HER2- PD-L1‒Positive Advanced Breast Cancer: Final Analysis of the Phase 3 KEYNOTE-B49 Study.
BACKGROUND We evaluated pembrolizumab plus chemotherapy versus chemotherapy alone in participants with PD-L1‒positive, hormone receptor-positive (HR+)/HER2- advanced breast cancer after progression on prior endocrine-based therapy (ET). PATIENTS AND METHODS Participants with locally recurrent inoperable or metastatic...