Merck reports interim KEYNOTE-052 data on Keytruda in urothelial cancer
Merck announced "positive" findings from the phase 2 KEYNOTE-052 study investigating the use of Keytruda in previously untreated patients with unresectable or metastatic urothelial cancer who are ineligible for cisplatin-based therapy. Data presented at the ESMO 2016 Congress showed an overall response rate of 24 percent in the total study population, which included patients with and without PD-L1 expression. Findings presented at ESMO 2016 are from the planned interim analysis of the first 100 patients, which was intended to evaluate ORR and determine the PD-L1-high expression cut-point as examined by expression in tumor and immune cells. Forty-five percent of patients had an Eastern Cooperative Oncology Group Performance Status score of two, 30 percent had a PS score of one, and 24 percent had a PS score of zero. In the total study population, ORR was 24 percent with a complete response rate of six percent. Review of the outcomes based on PD-L1 expression showed that in patients with PD-L1 expression of less than one percent, ORR was 18 percent with a complete response rate of three percent; in patients with PD-L1 expression greater than or equal to one percent and less than 10 percent, ORR was 15 percent with no complete responses; and, in patients expressing PD-L1 at levels equal to or greater than 10 percent, ORR was 37 percent with a complete response rate of 13 percent. Among the 24 percent of patients in the total study population who were responding to treatment, the median duration of response had not been reached -- range 1.4+ to 9.8+ months -- with 83 percent of patients having responses of six months or longer. The safety profile of Keytruda was consistent with that observed in previously reported studies. Five patients discontinued due to a treatment-related adverse event; there were no treatment-related deaths.