Patina: Targeted Therapy + Palbociclib for Metastatic Breast Cancer - Clinical Trial

We are doing this study to see if adding the study drug, palbociclib, to your current anti-HER2 cancer therapy and your endocrine therapy is better than anti-HER2 therapy plus endocrine therapy alone for people with breast cancer. We would like to know what effects, good or bad, palbociclib has on cancer by comparing it to current standard of care therapy, which is the combination of anti-HER2 and endocrine therapy.

HER2 Positive, ER Positive Breast Cancer

- Adult women and men with metastatic (spread to other places on the body), HER2 positive, hormone receptor positive breast cancer.
- Adults must have a disease-free period for at least 6 months after completing anti-HER2 cancer therapy before getting the metastatic breast cancer diagnosis.

If you agree to be in the study you will:
- Be randomized (put into one of two groups by chance like a flip of a coin)to get either:
--- Group 1: palbociclib (study drug), your current anti-HER2 cancer therapy (such as trastuzumab or pertuzumab) and endocrine therapy (such as letrozole or fulvestrant).
--- Group 2: Only get current anti-HER2 cancer therapy (such as trastuzumab or pertuzumab) and endocrine therapy (such as letrozole or fulvestrant).
- Have tests, exams, and procedures that are part of your standard care and for study purposes.
- Continue to receive the study drug as long as there are no bad side effects and the cancer does not become worse.
- Be in the study for 5 years after starting the study drug.