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Be Part of Research - Trial Details - 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)

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)

Not Recruiting

Open to: ALL

Age: 18.0 - N/A

Medical Conditions

Breast Neoplasms


This information is provided directly by researchers, and we recognise that it isn't always easy to understand. We are working with researchers to improve the accessibility of this information. In some summaries, you may come across links to external websites. These websites will have more information to help you better understand the study.


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.

Start dates may differ between countries and research sites. The research team are responsible for keeping the information up-to-date.  

The recruitment start and end dates are as follows:

Jun 2021 Dec 2027

INTERVENTIONAL

Intervention Type : BIOLOGICAL
Intervention Description : Intravenous (IV) infusion

Intervention Arm Group : Pembrolizumab + Chemotherapy;

Intervention Type : DRUG
Intervention Description : IV infusion

Intervention Arm Group : Pembrolizumab + Chemotherapy;Placebo + Chemotherapy;

Intervention Type : DRUG
Intervention Description : IV infusion

Intervention Arm Group : Pembrolizumab + Chemotherapy;Placebo + Chemotherapy;

Intervention Type : DRUG
Intervention Description : IV infusion

Intervention Arm Group : Pembrolizumab + Chemotherapy;Placebo + Chemotherapy;

Intervention Type : DRUG
Intervention Description : oral administration

Intervention Arm Group : Pembrolizumab + Chemotherapy;Placebo + Chemotherapy;

Intervention Type : DRUG
Intervention Description : IV infusion

Intervention Arm Group : Placebo + Chemotherapy;

Intervention Type : DRUG
Intervention Description : IV infusion

Intervention Arm Group : Placebo + Chemotherapy;



You can take part if:



You may not be able to take part if:


This is in the inclusion criteria above


Below are the locations for where you can take part in the trial. Please note that not all sites may be open.

  • Leicester Royal Infirmary-HOPE Clinical Trials Unit ( Site 1502)
    Leicester
    England
  • The Royal Cornwall Hospital ( Site 1507)
    Truro
    Cornwall
    TR1 3LJ
  • St Bartholomew's Hospital ( Site 1508)
    London
    England
    EC1A 7BE
  • The Christie ( Site 1510)
    Manchester
    England
    M20 4BX
  • North West Cancer Centre ( Site 1511)
    Londonderry
    London, City Of
    BT47 6SB
  • Guy's & St Thomas' NHS Foundation Trust ( Site 1501)
    London
    London, City Of
    SE1 9RT
  • Blackpool Victoria Hospital ( Site 1503)
    Blackpool
    Lancashire
    FY38NR


The study is sponsored by Merck Sharp & Dohme LLC




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Read full details for Trial ID: NCT04895358
Last updated 27 February 2025

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