Immune booster and radiation combo tested before breast cancer surgery

NCT ID NCT03366844

First seen Jun 27, 2026 · Last updated Jun 27, 2026

Summary

This study tests whether giving the immunotherapy drug pembrolizumab (Keytruda) along with a small dose of radiation to the tumor before standard treatment (surgery, chemotherapy, or radiation) is safe and helps the immune system fight breast cancer. About 66 people with operable breast cancer will receive two doses of pembrolizumab, with radiation given at the second dose. The goal is to see if this approach can boost immune activity in the tumor without delaying standard care.

What this could mean

Our plain-language read of the trial. This is informational only — not medical advice or a prediction.

Active substance
pembrolizumab (Keytruda) and radiation therapy
What this could lead to
If it works, this could point toward a way to make standard breast cancer treatments more effective by priming the immune system beforehand.
What could go wrong
This is a small, early-phase trial (Phase 1/2) with only 66 participants, so results may not apply to all patients. The combination may cause immune-related side effects or delays in standard care.

This is an AI summary of the original study and may miss details. Read our disclaimer.

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Conditions

The condition(s) this trial relates to.

As listed by the trial registrant

The condition terms exactly as the trial's registrant entered them.

Contacts and locations

Locations

  • Cedars-Sinai Medical Center

    Los Angeles, California, 90048, United States

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