DR-176 Responder study, Biomarker discovery study to identify patients with advanced urothelial cancer benefitting from pembrolizumab treatment.

Immune checkpoint inhibitors have been approved for first- and second-line treatment of metastatic urothelial cancer (mUC) patients, and lead to durable clinical responses in a small subset of patients. As a consequence many patients are being exposed to ineffective treatment with the risk of developing (severe) side effects. The aim of this study is to identify potential predictive markers for clinical benefit of immunotherapy. We will use the genomics data to identify predictors based on the sequencing but we will also combine it with other modalities such as staining of tumor biopsies and liquid biopsies. Furthermore, mechanisms underlying primary and acquired resistance to immunotherapy will be studied, potentially facilitating the development of improved (combinatorial) treatment strategies for mUC patients.

Martijn Lolkema Erasmus MC the Netherlands