Dr. Overman on Next Steps With Immunotherapy in mCRC

Michael J. Overman, MD, associate professor, Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, discusses next steps for the use of immunotherapy in the treatment of patients with metastatic colorectal cancer (mCRC).

Immunotherapy has had the most success in patients with tumors that express microsatellite instability-high (MSI-H) or mismatch repair deficiency (dMMR). These are types of DNA repair errors in a rare subset of patients that lead to various mutations, resulting in the increased immune response. Immunotherapy agent pembrolizumab (Keytruda) has a tumor agnostic indication for patients who express dMMR as it demonstrated good activity in this population, he adds. Ongoing trials are now looking to address the unanswered question of whether checkpoint inhibitors can move to the frontline setting.

The combination of nivolumab (Opdivo) and ipilimumab (Yervoy) has shown the most promise, but synergistic combinations are also being investigated, says Overman. For example, a combination comprised of a PD-1 inhibitor with a LAG3 inhibitor is currently being evaluated in the NCI-sponsored MATCH study.