Pembrolizumab in microsatellite-instability-high and mismatch-repair-deficient advanced solid tumors: updated results of the KEYNOTE-158 trial

Abstract

The phase 2 trial KEYNOTE-158 (NCT02628067) evaluated pembrolizumab in microsatellite-instability-high and mismatch-repair-deficient (MSI-H/dMMR) noncolorectal tumors. With 373 participants (95% with baseline MSI/dMMR documentation) and 4.5 years of follow-up, the primary endpoint of overall response rate was 33.8%. Secondary endpoints of duration of response, overall survival and progression-free survival were 63.2, 19.8 and 4.0 months, respectively. Grade >= 3 treatment-related adverse events occurred in 50 (13%) participants. These results further support pembrolizumab use in MSI-H/dMMR tumors.