Clinical Connection

This trial is not actively recruiting.

This trial has completed recruitment on this platform, and is no longer accepting new referrals.

MOUNTAINEER: A Clinical Trial for HER2+ Metastatic Colorectal Cancer

A study to test the safety and effectiveness of the combination of tucatinib and trastuzumab in people with HER2+ metastatic or unresectable colorectal cancer

Trial ID: NCT03043313

Trial Details

What’s the Study About?

We want to learn if an investigational drug called tucatinib can be used to treat HER2 positive (HER2+) colorectal cancer. Tucatinib is designed to find and stick to cancer cells that make the HER2 protein and prevent the cancer from growing. In this study, we want to find out if tucatinib alone or with trastuzumab (HERCEPTIN) is safe and effective for the treatment of HER2 positive metastatic and/or unresectable colorectal cancer.

If you take part in this study, you’ll be assigned to get tucatinib alone or with trastuzumab. You will be assigned your treatment randomly, like tossing a coin.

This is an open-label study. That means both you and the study team will know which study drug(s) you’re getting.

We know that each person is different and may not respond to a drug the same way. That’s why it’s important to include people from many different ages, genders, races and backgrounds. It will help us understand how our drug works and make sure it’s safe.


Estimated Enrollment

115 Participants



Eligibility Criteria

Participants must:
  • Be 18 or older
  • Have HER2+, metastatic and/or unresectable colorectal cancer
  • Have a positive HER2 result on a tumor sample. We can use a sample you had taken any time before joining the study
  • Have already been treated with flouropyrmidines (e.g., 5FU or capecitabine), oxaliplatin, irinotecan, and an anti-VEGF antibody
Participants must not:
  • Been treated with an anti-HER2 therapy before
  • Cancer that has spread to your nerves or spine (central nervous system) that has required treatment with steroids in the last month
  • Significant heart or lung disease. For example, you shouldn’t have heart failure, have had a heart attack, high blood pressure, or a stent placed in your heart

What Will Happen in the Study?

If you choose to take part in this study, we’ll do tests to see if you can be in the study. If you can be in the study and choose to take part, we’ll do tests to see if the study drug(s) can affect your cancer. If your cancer stays the same or gets better, and you don’t have any serious problems, you can keep getting the study drug(s) until the study is closed.

We’ll take blood samples for safety and research tests and to check on your disease. These are extra blood samples just for the study. You will also get blood drawn for your normal medical care.

At some visits, we’ll will give you questionnaires to fill out. There will also be a drug diary to complete each day during your treatment cycle.

We’ll ask you to come in and get an echocardiogram or MUGA scan about once every 12 weeks, and we’ll do an MRI or CT scan to look for signs of cancer at screening. While you’re on study treatment you will have an MRI or CT scan about once every 6 weeks. If you stop taking part in the study, you will have a scan about once every 9 weeks unless your cancer gets worse.

If you get tucatinib, you’ll swallow pills twice a day. If you get trastuzumab on the study you’ll also have an infusion into your vein (also called “IV”) once every 3 weeks.

If you get tucatinib alone you may be able to switch to tucatinib plus trastuzumab if your cancer isn’t getting better.

If you join this study, we’ll collect your health information for up to 5 years. You don’t need insurance to join this clinical trial and compensation for travel will be available.

You will need to travel to one of the study clinics taking part in this clinical trial. Sites are located in:

Actively Recruiting

  • Cleveland, Ohio, United States
  • Kansas City, Kansas, United States
  • Westwood, Kansas, United States
  • Las Vegas, Nevada, United States
  • Santa Rosa, California, United States
  • Long Beach, California, United States
  • Torrance, California, United States
  • Newport Beach, California, United States
  • Irvine, California, United States
  • Huntington Beach, California, United States
  • Palo Alto, CA , United States

Currently Inactive

  • (On hold) Lubbock, Texas, United States
  • (Completed enrollment) Indianapolis, Indiana, United States
  • (Awaiting confirmation) Gilbert, AZ, United States

Frequently Asked Questions (FAQs)