Study of Pembrolizumab (MK-3475) Plus Chemotherapy Versus Placebo Plus Chemotherapy for HR+/HER2- Locally Recurrent Inoperable or Metastatic Breast Cancer (MK-3475-B49/KEYNOTE-B49) (NCT04895358)
A Randomized, Double-blind, Placebo-controlled, Phase 3 Study of Pembrolizumab Plus Chemotherapy Versus Placebo Plus Chemotherapy for the Treatment of Chemotherapy-Candidate Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative (HR+/HER2-) Locally Recurrent Inoperable or Metastatic Breast Cancer (KEYNOTE-B49)
🩺 Plain-English Summary (8th-Grade Level)
The safety and efficacy of pembrolizumab plus the investigator's choice of chemotherapy will be assessed compared to placebo plus the investigator's choice of chemotherapy in the treatment of chemotherapy-candidate hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR+/HER2-) locally recurrent inoperable or metastatic breast cancer. The primary hypotheses are that the combination of pembrolizumab and chemotherapy is superior to placebo and chemotherapy in regards to Progression-Free Survival (PFS) in participants with programmed cell death-ligand 1 (PD-L1) combined positive score (CPS) ≥1. Prior to protocol amendment 7, participants who discontinued pembrolizumab/placebo with SD or better and subsequently experienced disease progression may have been eligible for up to 17 additional administrations of pembrolizumab if, upon unblinding, they were found to have received pembrolizumab, at the same dose and schedule used for the initial treatment period.
Who can join: Review the eligibility criteria below.
Location: University of Alabama at Birmingham-Medicine ( Site 0065) — Birmingham, Alabama
Age range: 18 Years
🧪 Interventions in This Study
📋 "Do I Qualify?" — 1-Minute Self Screener
Instant ChecklistFull eligibility criteria are available on the official NIH protocol. View the criteria ↗
📍 All Participating Trial Locations (256 Sites)
Showing the first 25 of 256 sites.
- University of Alabama at Birmingham-Medicine ( Site 0065) — Birmingham, Alabama
- Arizona Oncology Associates-Arizona Oncology ( Site 0049) — Tucson, Arizona
- Pacific Cancer Care ( Site 0023) — Monterey, California
- UCSF Medical Center at Mission Bay ( Site 0043) — San Francisco, California
- Georgetown University Medical Center-Department of Medicine and Oncology ( Site 0026) — Washington D.C., District of Columbia
- MedStar Washington Hospital Center ( Site 0063) — Washington D.C., District of Columbia
- Baptist MD Anderson Cancer Center ( Site 0013) — Jacksonville, Florida
- Miami Cancer Institute at Baptist Health, Inc. ( Site 0070) — Miami, Florida
- Miami Cancer Institute - Plantation ( Site 0076) — Plantation, Florida
- University Cancer & Blood Center, LLC ( Site 0032) — Athens, Georgia
- Northwest Georgia Oncology Centers, a Service of Wellstar Cobb Hospital-Research ( Site 0028) — Marietta, Georgia
- University of Illinois at Chicago ( Site 0061) — Chicago, Illinois
- Edward-Elmhurst Healthcare, Elmhurst Hospital-Nancy W. Knowles Cancer Center ( Site 0067) — Elmhurst, Illinois
- Edward-Elmhurst Healthcare, Edward Hospital-Edward Cancer Center ( Site 0066) — Naperville, Illinois
- Edward-Elmhurst Healthcare, Edward Hospital - Plainfield-Edward Cancer Center - Plainfield ( Site 00 — Plainfield, Illinois
- Orchard Healthcare Research Inc. ( Site 0037) — Skokie, Illinois
- Parkview Research Center at Parkview Regional Medical Center ( Site 0071) — Fort Wayne, Indiana
- McFarland Clinic, PC ( Site 0041) — Ames, Iowa
- Louisiana State University Health Sciences Shreveport ( Site 0072) — Shreveport, Louisiana
- CHRISTUS Highland-Oncology Research ( Site 0073) — Shreveport, Louisiana
- New England Cancer Specialists ( Site 0007) — Scarborough, Maine
- Greater Baltimore Medical Center-Medical Oncology/Hematology ( Site 0062) — Baltimore, Maryland
- MFSMC-HJWCI ( Site 0064) — Baltimore, Maryland
- MedStar Good Samaritan Hospital-Oncology Research ( Site 0069) — Baltimore, Maryland
- University of Massachusetts Medical School-Division of Hematology/Oncology ( Site 0052) — Worcester, Massachusetts
💰 Cost, Insurance & Patient Rights
- 100% Free Items: The investigational treatment and protocol-required procedures are supplied at zero cost by the sponsor.
- Routine Patient Care: Under federal law (ACA § 2709) and many state statutes, routine care costs are covered during participation.
- Voluntary Participation: You may withdraw at any time without affecting your standard medical care.
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💡 How to Participate
- Check the checklist above to see if you may qualify.
- Review the official NIH record below to find the coordinating site.
- Ask about the visit schedule, what is covered at no cost, and any travel support.
- Confirm with your own doctor before making a decision.