NEW YORK (GenomeWeb) – Merck announced this evening that it has received approval from the US Food and Drug Administration for its anti-PD-1 therapy Keytruda (pembrolizumab) for the treatment of patients with recurrent locally advanced or metastatic gastric or gastroesophageal junction (GEJ) adenocarcinoma whose tumors express PD-L1.
In conjunction with that approval, Agilent Technologies also announced that its Dako PD-L1 IHC 22C3 pharmDx assay has received expanded approval to act as a companion diagnostic for Keytruda in this new indication.
Gastric and GEJ cancer patients eligible for treatment with Keytruda must be determined to have 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, Merck said. This indication is approved under the FDA's accelerated approval regulations based on tumor response rate and durability of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in confirmatory trials.
Agilent's Dako PD-L1 IHC 22C3 pharmDx assay was first approved by the FDA in October 2015, in conjunction with Keytruda, for determining PD-L1 expression levels in patients with non-small cell lung cancer. It was granted expanded approval in October 2016 alongside Keytruda to determine expression status and inform treatment in a broader range of metastatic NSCLC patients.
"We are pleased that the US FDA approved the expansion of use for PD-L1 IHC 22C3 pharmDx assay, as it gives patients with gastric or GEJ cancer the possibility of having their tumor sample tested for PD-L1 expression, and determining eligibility for treatment with Keytruda," Jacob Thaysen, president of Agilent's diagnostics and genomics group, said in a statement.
This past May, Keytruda became the first cancer drug on the market to be approved for a tissue-agnostic, biomarker-guided indication when the FDA granted it accelerated approval for adult and pediatric patients with unresectable or metastatic solid tumors characterized by high microsatellite instability or mismatch repair deficiency.