This clinical trial is exploring a new treatment for patients with metastatic colorectal cancer (mCRC) that has not responded to standard treatments. Metastatic means the cancer has spread to other parts of the body. This study tests the combination of three drugs: irinotecan, TAS-102 (a combination of trifluridine and tipiracil), and bevacizumab. Patients will receive these drugs through an intravenous infusion (medicine given directly into the vein) and as pills. The trial will look at how well the treatment shrinks the tumor and how safe it is. Participants will need to visit the study center every two weeks for treatment and evaluations.

• The study requires visits every 14 days for treatment.
• Participants must have mCRC that hasn't responded to other treatments.
• Potential side effects and risks will be monitored closely.

To participate, patients must meet certain health criteria and cannot have certain other health conditions. If eligible, participants must be willing to sign a consent form agreeing to the study's guidelines.