Active not recruitingPHASE3INTERVENTIONAL

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)

This study is investigating a new treatment for breast cancer that has returned locally, can't be operated on, or has spread to other parts of the body (HR+/HER2- type). Researchers want to see if adding the drug pembrolizumab to standard chemotherapy works better and is safer than chemotherapy alone. They are particularly interested in patients whose cancer cells have a certain marker called PD-L1. The study is in its final phase (Phase 3), meaning it's comparing the new combination against the current standard treatment to understand how well it stops the cancer from growing.

At a glance

Status

Active not recruiting

Phase

PHASE3

Sponsor

Merck Sharp & Dohme LLC

Enrolment target

340

Start

18 Jun 2021

Estimated completion

18 Dec 2027

Breast Neoplasms

What is this study about?

This study, called KEYNOTE-B49, is looking into a new way to treat a specific type of breast cancer. This is for breast cancer that is Hormone Receptor-positive (HR+) and HER2-negative (HER2-), which means its cells have certain features. It's for cancer that has either come back in the same area and can't be removed by surgery, or has spread to other parts of the body. This is known as advanced breast cancer.

The main idea is to combine a drug called pembrolizumab with standard chemotherapy. Chemotherapy is a common treatment for cancer, but pembrolizumab is a newer type of drug that works with your body's immune system to fight cancer cells. Researchers want to find out if this combination therapy is more effective at stopping the cancer from growing or spreading compared to just using chemotherapy by itself.

They're especially interested in patients whose cancer cells show a certain marker called PD-L1. This marker might help predict who would benefit most from pembrolizumab. The study aims to see if the combination treatment can keep the cancer from worsening for longer, which doctors call "Progression-Free Survival."

Key takeaways

This study is testing a new combination of treatments for HR+/HER2- advanced breast cancer.
It combines a drug called pembrolizumab with standard chemotherapy.
The aim is to see if this new combination is more effective than chemotherapy alone.
Researchers are particularly interested in patients whose cancer cells have a specific marker called PD-L1.
This is a Phase 3 study, meaning it's a large trial to confirm treatment benefits.
Participation involves regular clinic visits for treatment and monitoring.

Who may be eligible?

To join this study, people must have a specific type of breast cancer that has either come back locally and can't be removed by surgery, or has spread to other parts of the body. This cancer must be HR+/HER2- and shouldn't have been treated with chemotherapy for advanced cancer before.

Participants must have already tried and progressed on hormone therapy. There are different situations for this: you might have tried two or more hormone therapies (including one with a CDK4/6 inhibitor), or you might have progressed quickly on a hormone therapy depending on when your cancer came back or how long you've been on treatment. The study team will check your specific treatment history to see if you fit one of these groups.

Also, a doctor must feel that chemotherapy is a suitable treatment option for you at this time. You'll need to be at least 18 years old.

Quick self-check

Do you have HR+/HER2- breast cancer that has come back locally (and can't be operated on) or has spread?
Have you already tried and progressed on hormone therapy for your advanced breast cancer?
Has your cancer progressed on specific prior treatments as described by your doctor?
Does your doctor think chemotherapy is a suitable option for you now?
Are you at least 18 years old?

This is a guide only — the research team will confirm whether you can take part.

What does participation involve?

If you join this study, you will be randomly assigned to one of two groups. One group will receive pembrolizumab plus chemotherapy, and the other will receive a placebo (an inactive substance) plus chemotherapy. You, your doctor, and the study team will not know which group you are in until after the study is over, unless there's a medical need to find out.

Taking part will involve regular visits to the clinic for treatments, check-ups, and tests to see how you're responding and to monitor any side effects. These tests might include blood samples, scans, and physical exams. The type and frequency of visits will depend on the specific chemotherapy chosen. The total duration of your participation, including follow-up, will be explained by the study team, but generally involves several months of treatment and continued monitoring.

Potential risks and benefits

Participating in this study might offer potential benefits, such as access to a new treatment combination that could be more effective in controlling your cancer than standard chemotherapy alone. However, there are also potential risks, as pembrolizumab and chemotherapy can both cause side effects. These can range from mild to more serious, and the study team will monitor you closely for them. You have the right to withdraw from the study at any time, for any reason, without it affecting your usual medical care.

Locations (256)

University of Alabama at Birmingham-Medicine ( Site 0065)
Birmingham, United States
Arizona Oncology Associates-Arizona Oncology ( Site 0049)
Tucson, United States
Pacific Cancer Care ( Site 0023)
Monterey, United States
UCSF Medical Center at Mission Bay ( Site 0043)
San Francisco, United States
Georgetown University Medical Center-Department of Medicine and Oncology ( Site 0026)
Washington D.C., United States
MedStar Washington Hospital Center ( Site 0063)
Washington D.C., United States
Baptist MD Anderson Cancer Center ( Site 0013)
Jacksonville, United States
Miami Cancer Institute at Baptist Health, Inc. ( Site 0070)
Miami, United States
Miami Cancer Institute - Plantation ( Site 0076)
Plantation, United States
University Cancer & Blood Center, LLC ( Site 0032)
Athens, United States
Northwest Georgia Oncology Centers, a Service of Wellstar Cobb Hospital-Research ( Site 0028)
Marietta, United States
University of Illinois at Chicago ( Site 0061)
Chicago, United States

+244 more sites — see the official record for the full list.

Common questions

What is HR+/HER2- breast cancer?

This is a type of breast cancer where the cells have receptors for hormones like oestrogen or progesterone (HR+) but don't have too much of a protein called HER2 (HER2-). This affects how it's treated.

What is pembrolizumab?

Pembrolizumab is a drug that helps your immune system recognise and fight cancer cells. It's a type of immunotherapy.

What does 'locally recurrent inoperable or metastatic' mean?

It means the cancer has come back in the nearby area but can't be removed by surgery, or it has spread to other parts of the body, like the bones or lungs.

Will I definitely receive the new drug?

No, you will be randomly assigned to one of two groups. One group gets pembrolizumab plus chemotherapy, and the other gets a placebo (dummy drug) plus chemotherapy. This is to fairly compare the new treatment.

What is 'Progression-Free Survival'?

This is a way doctors measure how long a person lives with cancer without the disease getting worse or spreading. The goal of this study is to increase this time.