On June 19, 2018, the FDA revised the prescribing label for atezolizumab (Tecentriq; Genentech) and for pembrolizumab (Keytruda; Merck) to limit the use of these 2 immunotherapies in patients with locally advanced or metastatic urothelial cancer only to patients who are ineligible for cisplatin-containing chemotherapy.
This revised indication was based on results from clinical trials showing decreased survival associated with the use of pembrolizumab or atezolizumab as monotherapy compared with platinum-based chemotherapy in patients with metastatic urothelial cancer who had not received previous therapy and had a low expression of the PD-L1 protein. The labels of both drugs have been revised to include this limitation in the indication.
Then on July 2, 2018, the FDA approved the Ventana PD-L1 (SP142) Assay to identify patients with PD-L1 expression of ≥5% in immune cells in urothelial carcinoma. The FDA approved this test as a companion diagnostic to atezolizumab. This test should be used to identify patients with locally advanced or metastatic urothelial carcinoma who should receive treatment with atezolizumab. The prescribing information of atezolizumab was revised to reflect this update.
And on August 16, 2018, the FDA approved the Dako PD-L1 IHC 22C3 PharmDx Assay as a companion diagnostic to pembrolizumab to identify patients with locally advanced or metastatic urothelial carcinoma who are ineligible for cisplatin therapy and whose tumor express PD-L1 CPS ≥10, for treatment with pembrolizumab. The prescribing information of pembrolizumab was revised to reflect this update.