KEYNOTE-756: A randomized, double-blind, phase III study of pembrolizumab or placebo with neoadjuvant chemotherapy and adjuvant endocrine therapy for high-risk, early-stage, ER /HER2-breast cancer

Abstract

Background A high-risk subpopulation of ER+/HER2− breast cancer (BC) is characterized by high-grade tumors, decreased sensitivity to endocrine therapy (ET), higher responsiveness to chemotherapy (CT), and worse prognosis. Prior studies suggest that increased pathological complete response (pCR) rates after neoadjuvant CT may have a substantial impact for patients with high-risk, early-stage, HR+/HER2− BC. KEYNOTE-756 (NCT03725059) is a global, randomized, double-blind, phase 3 study of pembrolizumab (vs placebo) + CT as neoadjuvant treatment followed by pembrolizumab (vs placebo) + ET as adjuvant treatment for patients with high-risk, early-stage, ER+/HER2− BC. Trial design Patients with T1c..