Agilent Technologies’ PD-L1 assay received an expanded label in Europe to help guide the use of first-line Keytruda in urothelial carcinoma. Physicians can now use the assay to help identify patients who are ineligible for cisplatin treatment and may respond to the immunotherapy.
The Santa Clara, California-based Agilent developed the PD-L1 pharmDx assay in partnership with Merck, maker of Keytruda.
The diagnostic examines PD-L1 expression in urothelial carcinoma tissues using combined positive score—a measure of PD-L1 expressing cells, including tumor cells, lymphocytes and macrophages, compared to the total number of viable tumor cells.
“We are pleased that PD-L1 IHC 22C3 pharmDx will help physicians identify urothelial carcinoma patients for whom Keytruda may be an appropriate first-line treatment option,” Sam Raha, president of Agilent's diagnostics and genomics group, said in a statement.
“Being able to support the use of immuno-oncology therapeutics by bringing their associated diagnostics to market is truly encouraging,” Raha said.
The PD-L1 IHC 22C3 pharmDx assay can also assist oncologists in identifying non-small cell lung cancer patients eligible for Keytruda treatment using tumor proportion score, or the percentage of viable tumor cells expressing PD-L1, with values of 50% or more determining a positive result.
The European Medicines Agency’s Committee for Medicinal Products for Human Use recently adopted a positive opinion for Keytruda in first-line metastatic nonsquamous NSCLC, in combination with pemetrexed and platinum chemotherapy but regardless of PD-L1 expression, though it is not yet approved.
RELATED: In a monster showing, Merck's Keytruda combo slashes lung cancer death risk by half
In June, the FDA expanded assay’s use to cover Keytruda treatment in cervical cancer patients, making it the first IHC test approved for determining PD-L1 expression in the indication. Other previous approvals include NSCLC and gastric or gastroesophageal junction adenocarcinoma.
However, the FDA also narrowed the labels of Merck’s Keytruda and Roche’s Tecentriq in locally advanced or metastatic bladder cancer patients that are not eligible for cisplatin chemotherapy.
Specifically, Keytruda is now cleared only for patients whose tumors express PD-L1 with a combined positive score of 10 or higher, while Tecentriq can be used where PD-L1 immune cells cover 5% or more of the tumor’s area. Patients ineligible for any platinum-containing therapy can still take either drug, regardless of PD-L1 status.