Joaquim Bellmunt, MD, PhD, associate professor of medicine, Harvard Medical School, director, Bladder Cancer Center, Dana-Farber Cancer Institute, discusses PD-L1 data with pembrolizumab (Keytruda) in patients with bladder cancer.
The way that PD-L1 is being scored with pembrolizumab in patients with bladder cancer is different than scores being used for other drugs, such as atezolizumab (Tecentriq), says Bellmunt. For pembrolizumab, physicians are using staining in tumor cells and immune cells divided by the number of tumor cells. In the initial report of the study, it was established that a patient with a score of more than 10% might derive benefit from pembrolizumab, says Bellmunt.
However, there was not a difference in patients who had a PD-L1–positivity score of more than 10%. The benefit was there and the hazard ratio was much better, but there was no change in terms of median survival or in terms of substantial improvement, explains Bellmunt. Therefore, PD-L1 in the pembrolizumab-treated patients does not seem to impact therapeutic decision.