RecruitingPHASE2INTERVENTIONAL

Neoadjuvant, SBRT With Intratumoural Pembrolizumab Followed by Neoadjuvant Chemotherapy in Breast Cancer

This study is investigating a new treatment approach for specific types of breast cancer before patients receive standard chemotherapy. Researchers want to see if combining a precise form of radiation therapy, called SBRT, with a drug called pembrolizumab (also known as KEYTRUDA®) can boost the body's immune response against cancer. The idea is that this combination might make the cancer cells more sensitive to subsequent chemotherapy. They are hoping to improve how well patients respond to treatment. This is a Phase 2 study, meaning it's checking the safety and effectiveness of this new combination in a small group of people.

At a glance

Status

Recruiting

Phase

PHASE2

Sponsor

London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's

Enrolment target

Start

19 Jan 2026

Estimated completion

01 Feb 2029

Breast Cancer Breast Cancer Stage II Breast Cancer Stage III Breast Cancer Invasive Breast Cancer Triple Negative

What is this study about?

This study is exploring a new way to treat certain types of breast cancer, specifically those that are high-risk. The main idea is to try a combination of treatments *before* patients receive their main course of chemotherapy. The treatment starts with a very focused type of radiation, called SBRT, combined with two injections of a medicine called pembrolizumab. After these initial steps, patients would then go on to have their usual chemotherapy.

The researchers think that the special radiation and pembrolizumab might 'wake up' the body's immune system to better fight the cancer. The hope is that by doing this first, the subsequent chemotherapy will be more effective at shrinking or getting rid of the cancer. They want to see if this combined approach leads to better results than chemotherapy alone.

Previous studies have hinted that SBRT radiation might help the immune system. Adding pembrolizumab, which is a drug that helps the immune system find and attack cancer cells, could potentially make this effect even stronger. This study is a step towards understanding if this new combination is safe and if it can improve how well breast cancer is treated.

Key takeaways

This study is testing a new combination for high-risk breast cancer.
It uses targeted radiation (SBRT) and an immune-boosting drug (pembrolizumab).
These are given *before* your standard chemotherapy.
The goal is to make chemotherapy work better by 'waking up' your immune system.
Participation is for adults with specific breast cancer types.

Who may be eligible?

This study is for adults aged 18 and over who have certain types of breast cancer. Specifically, it's for those with invasive ductal carcinoma (including some with lobular features) that is categorised as stage IIB or III. Some stage IIA breast cancers, particularly triple-negative or HER2-positive types, might also be eligible.

You would need to be planning to have chemotherapy before surgery (neoadjuvant chemotherapy) and be able to have small tissue samples (biopsies) taken and receive the pembrolizumab injections. Your doctor would need to be able to feel the lump.

There are also some reasons why you might not be able to join. For example, if you've already had treatment for this breast cancer, had radiation to the same breast before, or if you have inflammatory breast cancer. Certain serious health conditions, autoimmune diseases, or if you are pregnant or breastfeeding, would also mean you couldn't take part. You also shouldn't have any signs of the cancer having spread to other parts of your body.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you 18 years old or older?
Do you have invasive ductal breast cancer (Stage IIB, III, or some IIA types)?
Are you planning to receive chemotherapy before surgery?
Have you not had any previous treatment for this specific breast cancer?
Is your breast cancer *not* inflammatory, or spread to other parts of your body?

Answer every question to see your result.

What does participation involve?

If you decide to take part in this study, you would first have a special type of radiation treatment called SBRT. This is a very focused radiation therapy. During this period, you would also receive two injections of the medicine pembrolizumab into the tumour. After this initial treatment phase, you would then receive your standard neoadjuvant chemotherapy, which is the chemotherapy given before surgery.

Throughout the study, you would have regular check-ups, which might include blood tests, imaging scans, and tissue samples (biopsies) to see how you are responding to the treatment and to monitor for any side effects. The exact number of visits and tests would be explained to you by the study team. The total duration of your participation would cover the SBRT, pembrolizumab, chemotherapy, and follow-up assessments.

Potential risks and benefits

Potential benefits of joining this study could include receiving a new experimental treatment that might make your standard chemotherapy more effective against your breast cancer. You would also be closely monitored by a specialised medical team. However, as it is a new combination, there are potential risks and side effects from both the SBRT radiation and pembrolizumab that are not fully understood in this specific combination. These could be different from what is usually expected from each treatment alone. You would be fully informed about all known risks before making a decision. Remember, taking part in any clinical study is always voluntary, and you have the right to withdraw at any time without affecting your usual medical care.

Locations (2)

St. Joseph's Health Care London
Verified postcode
London, Canada· Not yet recruiting
St. Joseph's Health Care London
Verified postcode
London, Canada· Recruiting

Common questions

What is SBRT?

SBRT stands for Stereotactic Body Radiation Therapy. It's a very precise type of radiation that delivers high doses of radiation to the cancer while trying to protect healthy tissues around it.

What is pembrolizumab?

Pembrolizumab (also known as KEYTRUDA®) is a type of immunotherapy medicine. It helps your body's own immune system find and fight cancer cells.

Why are they doing this before chemotherapy?

The researchers think that giving the SBRT and pembrolizumab first might 'prime' or prepare your immune system, making the cancer cells more sensitive and responsive to the chemotherapy you'll receive afterward.

What does 'high-risk breast cancer' mean?

High-risk breast cancer generally refers to cancers that have certain features that make them more likely to grow or spread, or those that might not respond as well to standard treatments alone.

Will I still have surgery?

This study involves treatment *before* surgery (neoadjuvant treatment). After completing the study treatments and chemotherapy, your doctor would discuss your next steps, which would typically include surgery.

How to find out more

Muriel Brackstone, MD, PhD

muriel.brackstone@lhsc.on.ca 519-685-8500 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.