NEW YORK (360Dx) – Agilent Technologies announced on Tuesday that the US Food and Drug Administration has expanded its approval of the firm's Dako PD-L1 IHC 22C3 pharmDx assay as a companion diagnostic test for Merck's anti-PD1 immunotherapy pembrolizumab (Keytruda) for non-small cell lung cancer (NSCLC).
Merck and Agilent's Dako subsidiary developed the assay in partnership, and the FDA initially approved it in October 2015 to determine whether a patient with advanced NSCLC was likely to respond to Keytruda. In October 2016, the FDA expanded the assay's approval as a CDx for Keytruda to determine expression status and inform treatment in a broader range of metastatic NSCLC patients.
Now, Agilent said, the assay can be used to identify patients with stage III NSCLC who are not candidates for surgical resection or definitive chemoradiation, or patients with metastatic NSCLC whose tumors express a PD-L1 Tumor Proportion Score greater than or equal to 1 percent, and who are eligible for first-line treatment with Keytruda. This expanded indication will enable pathologists to identify a larger population of previously untreated patients who are now eligible for treatment, the company added.
"Anti-PD-1 therapies are a promising treatment class for many cancer types, and PD-L1 testing provides key information to physicians managing stage III or metastatic NSCLC patients," Sam Raha, president of Agilent's diagnostics and genomics group, said in a statement. "The updated FDA approval of PD-L1 IHC 22C3 pharmDx broadens the scope of patients that can be identified for first-line treatment with Keytruda and offers new hope to the many patients diagnosed with stage III or metastatic NSCLC."
In September 2017, the FDA approved the Dako assay as a CDx for Keytruda for gastric or gastroesophageal junction adenocarcinoma, and followed that with an approval for use in cervical cancer patients in June 2018 and in urothelial carcinoma patients in August 2018.
The diagnostic was also granted CE marking in August 2016 as a CDx for Keytruda for patients with previously treated, advanced NSCLC with PD-L1 expressing tumors. In January 2017, the CE marking was expanded to include patients with metastatic NSCLC with no EGFR or ALK mutations who had not yet been treated. And in August 2018, the CE marking was expanded again to include urothelial carcinoma.