Merck has secured the US Food and Drug Administration (FDA) priority review and accepted the supplemental Biologics License Application (sBLA) for KEYTRUDA (pembrolizumab) to treat a type of metastatic solid tumours.

The pharmaceutical firm has filed the sBLA seeking fast-track approval of KEYTRUDA for the treatment of unresectable or metastatic solid tumours in patients with no satisfactory alternative treatment options.

The US regulatory agency has set 16 June 2020, as prescription drug user fee act (PDUFA), or target action date.

Merck Research Laboratories clinical research vice president Scot Ebbinghaus said: “From the start, biomarker research has been a critical aspect of our clinical program evaluating KEYTRUDA monotherapy. TMB has been an area of scientific interest to help identify patients most likely to benefit from KEYTRUDA.

“We look forward to working with the FDA throughout the review process to help bring KEYTRUDA monotherapy to patients with cancer in the second-line or higher treatment setting, where options remain limited.”

Merck’s sBLA was supported by the results from Phase 2 KEYNOTE-158 trial

KEYTRUDA is a humanised monoclonal antibody designed to block the interaction between PD-1 and its ligands, PD-L1 and PD-L2. The drug is used as an anti-PD-1 therapy that enables the body’s immune system to detect and fight tumour cells.

Merck said that its sBLA was supported by the results from Phase 2 KEYNOTE-158 trial, a multicentre, multi-cohort, non-randomized, open-label trial evaluating KEYTRUDA in patients with solid tumours.

In addition, the FDA approval for KEYTRUDA as the first cancer treatment based on a biomarker, regardless of cancer type, in microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) solid tumours was also supported by the KEYNOTE-158 trial.

In the study, the tumour response was assessed every nine weeks per response evaluation criteria in solid tumours by independent, central, blinded radiographic review, said the company.

Objective response rate (ORR) and duration of response (DOR), assessed by blinded independent central review (BICR) according to RECIST v1.1, include the primary efficacy outcome measures.