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)
Summary
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.
Timeline
- Start
- 2021-06-18
- Primary completion
- 2027-12-18
- Completion
- 2027-12-18
Drugs
| Evaluation | Drug | Modality | Dose | Route |
|---|---|---|---|---|
| Subject | Pembrolizumab | Monoclonal antibody | 200 mg | Intravenous |
| Background | Capecitabine | Small molecule | 1000 mg/m2 | Oral |
| Background | Doxorubicin | Other / unclassified | 50 mg/m2 | Intravenous |
| Background | Nab-paclitaxel | Small molecule | 100 mg/m2 | Intravenous |
| Background | Paclitaxel | Small molecule | 90 mg/m2 | Intravenous |