This study is looking at how safe and effective two different treatments for a type of cancer called colorectal cancer (CRC) are. CRC affects the large intestine and can spread to other parts of the body, which is called metastatic colorectal cancer (mCRC). Researchers want to see how well an investigational drug called ABBV-400 works compared to another treatment made of pills called LONSURF plus a drug given through a vein (IV) named bevacizumab.

The study will last about 4 years. It has two stages and involves about 460 adults from many countries. In the first stage, participants get different doses of ABBV-400. In the second stage, they’ll get either the best dose of ABBV-400 or the standard treatment with LONSURF and bevacizumab. This study means more hospital or clinic visits than usual because doctors will often check how the treatment is working and look for any side effects.

• Study duration is approximately 4 years.
• Regular hospital visits for check-ups and tests.
• Participants may experience higher treatment burdens.