A Phase II Study of Abemaciclib plus Pembrolizumab Immunotherapy for Patients with Metastatic Breast Cancer


Full Title

A Phase 1b Study of Abemaciclib in Combination with Pembrolizumab for Patients with Hormone Receptor Positive, HER2 Negative Breast Cancer


In this study, researchers are evaluating the safety and effectiveness of combining two drugs to treat patients with metastatic breast cancer that is fueled by estrogen or progesterone (“hormone receptor-positive”) and does not produce the HER2 protein (“HER2-negative”). The two drugs are abemaciclib and pembrolizumab. Doctors believe that combining them may be more effective than using either drug alone.

Abemaciclib is designed to inhibit cancer growth by blocking cyclin-dependent kinases (CDK), enzymes which cancer cells need to grow and divide. It is taken orally (by mouth).

Pembrolizumab is a form of immunotherapy. It works by blocking a molecule called PD-1 that shuts down the immune response. Blocking PD-1 can allow the immune system to detect and attack cancer cells. Pembrolizumab is already approved to treat several cancers; its use in this study is considered investigational. It is given intravenously (by vein).


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

  • Patients must have metastatic hormone receptor-positive HER2-negative breast cancer that has continued to grow despite one or two prior regimens of chemotherapy for metastatic disease.
  • Patients must recover from the serious side effects of previous treatments before entering the study.
  • 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. Maura Dickler at 646-888-5456.