Merck announced that the U.S. Food and Drug Administration (FDA) has approved KEYTRUDA, Merck's anti-PD-1 therapy, as a single agent, for adjuvant treatment following surgical resection and platinum-based chemotherapy for adult patients with stage IB (T2a =4 centimeters [cm]), II, or IIIA non-small cell lung cancer (NSCLC). The approval is based on data from the pivotal Phase 3 KEYNOTE-091 trial, also known as EORTC-1416-LCG/ETOP-8-15 – PEARLS. The major efficacy outcome measure was investigator-assessed disease-free survival (DFS).

In patients who received adjuvant platinum-based chemotherapy following surgical resection, KEYTRUDA reduced the risk of disease recurrence or death by 27% (hazard ratio [HR]=0.73 [95% CI, 0.60-0.89]) versus placebo regardless of PD-L1 expression. The median DFS in patients regardless of PD-L1 expression who received adjuvant platinum-based chemotherapy following surgical resection was nearly five years (58.7 months) for the KEYTRUDA arm versus nearly three years (34.9 months) for the placebo arm, translating to a nearly two-year (23.8 months) DFS improvement versus placebo. In an exploratory subgroup analysis of the 167 patients (14%) who did not receive adjuvant chemotherapy, the DFS HR was 1.25 (95% CI, 0.76-2.05).