Merck received approval from the FDA for KEYTRUDA, an anti-PD-1 therapy, as a single agent, for adjuvant treatment following surgical resection and platinum-based chemotherapy for adult patients with stage IB, II, or IIIA non-small cell lung cancer (NSCLC).
 
The approval is based on data from the pivotal Phase 3 KEYNOTE-091 trial. 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% 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. 
 
The adverse reactions observed in KEYNOTE-091 were generally similar to those occurring in other patients with NSCLC receiving KEYTRUDA as a single agent, with the exception of hypothyroidism (22%), hyperthyroidism (11%), and pneumonitis (7%). Two fatal adverse reactions of myocarditis occurred.
 
With this approval, KEYTRUDA is the only immunotherapy with an approved option for NSCLC regardless of PD-L1 expression in both the adjuvant and metastatic settings.