Merck’s Keytruda receives accelerated FDA approval for GEJ adenocarcinoma

Merck’s Keytruda (pembrolizumab) has received approval from the US Food and Drug Administration (FDA) to treat patients with recurrent locally advanced or metastatic gastric or gastroesophageal junction (GEJ) adenocarcinoma.

The therapy has been approved to treat GEJ adenocarcinoma patients whose tumours express PD-L1 (Combined Positive Score (CPS) ≥1) as determined by an FDA-approved test, with disease progression on or after two or more prior lines of therapy, including fluoropyrimidine and platinum-containing chemotherapy and if appropriate, HER2 / neu-targeted therapy.

Keytruda is an anti-programmed death receptor-1 (PD-1) therapy that increases the ability of the patient’s immune system to help detect and combat tumour cells.

It is a humanised monoclonal antibody that blocks the interaction between PD-1 and its ligands, PD-L1 and PD-L2, which in turn activates T-lymphocytes that may affect both tumour cells and healthy cells.

Merck Research Laboratories president Dr Roger M. Perlmutter said: "Keytruda is now the first PD-1 checkpoint inhibitor approved in the US for previously treated advanced gastric or GEJ cancer, helping to address a recognised treatment gap.

"This approval marks another milestone - the tenth new indication for Keytruda in just three years - which further demonstrates both our commitment to patients and the progress we have made in the fight against many cancers."

The additional FDA approval was based on data obtained from a global, multicentre, non-randomised, open-label, multi-cohort KEYNOTE-059 trial.

The trial involved 259 patients with gastric or GEJ adenocarcinoma who progressed on at least two prior systemic treatments for advanced disease.

Previous treatment of the patients must have included a fluoropyrimidine and platinum doublet or the HER2 / neu-positive patients must have previously been treated with approved HER2 / neu-targeted therapy.

In April last year, the FDA granted breakthrough therapy designation for Keytruda to treat patients with relapsed or refractory classical Hodgkin lymphoma (cHL).