- The US Food and Drug Administration (FDA) has approved pembrolizumab (Keytruda) for the first-line treatment of patients with unresectable or metastatic microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) colorectal cancer (CRC).
- The recommended dose is 200 mg every 3 weeks or 400 mg every 6 weeks.
Why this matters
- Pembrolizumab has demonstrated robust antitumor activity and a favorable safety profile in multiple tumor types.
- The approval was based on data from the multicenter, randomized KEYNOTE-177 trial.
- 307 patients with previously untreated unresectable or metastatic MSI-H/dMMR CRC were randomly assigned to either pembrolizumab (n=153) or investigator choice of chemotherapy (n=154).
- Pembrolizumab monotherapy vs chemotherapy group had:
- Lower risk for disease progression or death (HR, 0.60; 95% CI, 0.45-0.80; P=.0004);
- Better PFS (16.5 vs 8.2 months);
- Better overall response rate (44% vs 33%);
- Better complete response (11% vs 4%);
- Fewer grade ≥3 treatment-related adverse events (AEs; 22% vs 66%); and
- More immune-mediated AEs and infusion reactions (31% vs 13%).
For Prescribing Information, click here.