MSD has pulled back its application to market Keytruda (pembrolizumab) in the European Union in combination with pemetrexed and carboplatin as a first-line treatment for metastatic nonsquamous non-small cell lung cancer (NSCLC).

The combination has already received clearance in the US, but according to reports the European Medicines Agency’s Committee for Medicinal Products for Human Use (CHMP) was reluctant to back approval at this time.

The application centered on findings from a cohort of the KEYNOTE-021 trial, and MSD stressed that it is “confident in the clinical data” which “demonstrated significant improvements in overall response rate (ORR) and progression-free survival (PFS) for the Keytruda combination regimen compared to chemotherapy alone”.

Reuters cited company spokeswoman Pam Eisele as saying that there had not yet been a decision on when the European application would be resubmitted, but that there would be opportunities to conduct interim analyses of trial data.

MSD also highlighted that a number of studies evaluating Keytruda in combination with chemotherapy in the first-line NSCLC setting are also ongoing, which will be shared with regulatory authorities and the medical community as they become available.

The PD-1 inhibitor has already racked up a number of approvals both as a standalone agent and in combination with other therapies across lung cancer, melanoma, head and neck cancer, classical Hodgkin lymphoma, urothelial carcinoma, Microsatellite Instability-High (MSI-H) Cancer and gastric cancer.