FDA Approves Frontline Pembrolizumab for MSI-H/dMMR Metastatic CRC

The FDA has approved pembrolizumab (Keytruda) for the first-line treatment of patients with unresectable or metastatic microsatellite instability—high or mismatch repair deficient colorectal cancer. This marks the first immunotherapy approved for this patient population as a first-line treatment and which is administered to patients without also giving chemotherapy.

"Metastatic colorectal cancer is a serious and life-threatening disease with a poor prognosis. Available current therapy with chemotherapy combinations and other biologics are associated with substantial toxicity," said Richard Pazdur, M.D., director of the FDA's Oncology Center of Excellence and acting director of the Office of Oncologic Diseases in the FDA's Center for Drug Evaluation and Research. "Having a non-chemotherapy option available for selected patients is a noteworthy paradigm shift in treatment."

The decision was based on results from one multicenter, international, open-label, active-controlled, randomized trial that compared Keytruda with chemotherapy treatment in 307 patients with MSI-H or dMMR metastatic colorectal cancer. The study demonstrated a statistically significant improvement in progression-free survival (PFS) as assessed by blinded independent review. Median PFS was 16.5 months in the Keytruda group and 8.2 months in the standard of care group. Longer-term analysis is needed to assess for an effect on survival.

This article was originally published on OncLive as, "FDA Approves First-Line Pembrolizumab for MSI-H/dMMR Metastatic Colorectal Cancer."