Merck & Co. announced Wednesday that the FDA awarded accelerated approval to Keytruda (pembrolizumab), in combination with Eli Lilly's Alimta (pemetrexed) and carboplatin, for use in previously untreated patients with metastatic non-squamous non-small-cell lung cancer (NSCLC) irrespective of PD-L1 expression. The approval follows clearance of the drug as monotherapy for patients with metastatic NSCLC whose tumours have high PD-L1 expression, with no EGFR or ALK genomic tumour aberrations. Merck Research Laboratories president Roger Perlmutter remarked "the improved responses seen with the Keytruda plus [Alimta]/carboplatin regimen are significant, and highlight the importance of finding new approaches that address the unmet needs of patients with metastatic non-squamous [NSCLC]." 

The approval of the immunotherapy was supported by safety and efficacy data from the KEYNOTE-021 study's G cohort released in October last year, which showed that Keytruda plus Alimta and carboplatin was associated with an overall response rate of 55 percent, compared to 29 percent for Alimta and carboplatin alone. In addition, Merck noted that the three-drug regimen reduced the risk of death or disease progression by 47 percent. 

Keytruda, which had sales of $1.4 billion last year, was initially granted accelerated approval by the FDA in 2014 for the treatment of advanced or unresectable melanoma, becoming the first PD-1 inhibitor approved in the US. The drug was later authorised for use in certain patients with recurrent or metastatic head and neck squamous cell carcinoma, while the therapy was approved earlier this year for the treatment of certain adults and children with refractory classical Hodgkin lymphoma.

For related analysis, see ViewPoints: Merck & Co. continues to win the key plays in immuno-oncology race. See also Physician Views Poll Results: Keytruda's momentum in NSCLC.