MOUNTAINEER for Metastatic Colorectal Cancer - Clinical Trial

We are doing this study to look at the effects (good and/or bad) of taking study drugs Tucatinib and Trastuzumab has on you and your metastatic colorectal cancer.

Metastatic Colorectal Cancer

Adults who:
- Are diagnosed with metastatic colorectal cancer
- Have a positive test for HER2 overexpression or amplification
- Have not been treated with anti-HER2 therapy

If you choose to join this study, you will:
- Get the study drugs tucatinib and trastuzumab
-- Tucatinib is given by mouth twice a day and trastuzumab is given into your arm the first day of every 21 days in the clinic at Duke
-- This cycle will be repeated until your cancer gets worse or you have bad side effects or you choose to stop the study for any reason.
- Have tests, exams and procedures that are part of your standard of care and for study purposes. Clinic visits will usually last 4-5 hours