The US Food and Drug Administration has issued an accelerated approval for Merck & Co’s immunotherapy Keytruda in combination with pemetrexed (Eli Lilly’s Alimta) and carboplatin (pem/carbo) for the first-line treatment of metastatic nonsquamous non-small cell lung cancer (NSCLC).

The approval was based on data from the KEYNOTE-021 trial showing that the objective response rate (ORR) for the combination was nearly double that seen for pem/carbo alone (55 percent versus 29 percent, respectively).

This data also showed that, among patients who received Keytruda (pembrolizumab) and pem/carbo, 93 percent had a duration of response of six months or more compared to 81 percent in the control group, as well as an improvement in the amount of time patients lived without their disease worsening, with a median progression free survival of 13.0 months compared to 8.9 months.

“The improved responses seen with the Keytruda plus pemetrexed/carboplatin regimen are significant, and highlight the importance of finding new approaches that address the unmet needs of patients with metastatic nonsquamous non-small cell lung cancer,” said Dr Roger M. Perlmutter, president, Merck Research Laboratories.

The accelerated approval means that Keytruda is now the only anti-PD-1 approved in the first-line setting as both monotherapy and combination therapy for appropriate patients with metastatic NSCLC, but its continued clearance in this setting may be contingent upon verification of clinical benefit in further clinical trials.