A Phase II Study of Pembrolizumab Immunotherapy or Placebo after Surgery in Patients with Solid Tumors Containing Certain Genetic Changes


Full Title

A Single-Arm Pilot Study of Adjuvant Pembrolizumab in Patients with MSI-H Tumors with Persistent Circulating Tumor DNA Following Surgery


The purpose of this study is to assess the safety of the immunotherapy drug pembrolizumab and to find out how well it works to prevent cancer from coming back in people who have had a solid tumor surgically removed, but who still have tumor cells in their blood. Patients in this study will have a genetic marker called “high microsatellite instability,” which means there is a strong chance their tumor may come back.

Pembrolizumab boosts the power of the immune system against cancer by blocking PD-1, a protein cancer cells use to evade detection by the immune system, thereby enabling the immune system to find and kill cancer cells. It is approved for treating a variety of solid tumors, including previously treated tumors with high microsatellite instability. It is given intravenously (by vein).

Patients will receive pembrolizumab or a placebo (inactive drug) after cancer surgery.

Who Can Join

To be eligible for this study, patients must meet several criteria, including but not limited to the following:

  • Patients must have a solid tumor with high microsatellite instability that was completely removed with surgery.
  • Patients must show evidence of tumor cells circulating in the blood after cancer surgery.
  • Patients with metastatic or recurrent cancer may not participate.
  • Prior chemotherapy, targeted therapy, or radiation therapy is permitted but must have been completed 2 or more weeks before entering the study. Prior immunotherapy is not permitted.
  • Patients must be physically well enough that they are fully ambulatory, capable of all self care, and are capable of all but physically strenuous activities. As an example, patients must be well enough that they would be able to carry out office work or light housework.
  • This study is for patients age 18 and older.

For more information about this study and to inquire about eligibility, please contact Dr. Yelena Janjigian at 646-888-4186.






Dmitriy Zamarin


ClinicalTrials.gov ID