A Study of Tucatinib With Trastuzumab and mFOLFOX6 Versus Standard of Care Treatment in First-line HER2+ Metastatic Colorectal Cancer

To join this study, your doctor will first check if you meet certain requirements. You need to have bowel cancer that has either spread to other parts of your body or cannot be removed by surgery. This cancer must also be confirmed as 'HER2-positive,' which means your cancer cells have a particular protein that can be targeted by these new medicines. You also need to have what's called a 'RAS wild-type' cancer, which doctors will check for. Your general health should be good enough for you to participate in a clinical trial, meaning you can usually do most of your normal daily activities without much trouble.

If you join this study, you'll be randomly assigned to one of two groups. One group will receive the study drug combination (tucatinib, trastuzumab, and mFOLFOX6), and the other will receive a standard treatment which could be mFOLFOX6 alone, or with bevacizumab, or with cetuximab. You already know mFOLFOX6 is a combination of several medicines.

Throughout the study, you'll have regular hospital visits for check-ups, blood tests, and scans to see how the treatment is working and to monitor any side effects. You'll take your medicines as directed by the study team. They will explain how long your treatment will last and how often you'll need to visit the hospital. There will also be follow-up appointments after your treatment finishes to see how you are doing long-term. The total duration of your participation, including regular treatment and follow-up, will be made clear to you by the study team.