(UroToday.com) Cisplatin and gemcitabine is a first line chemotherapy option for patients with metastatic urothelial carcinoma who are medically eligible to receive cisplatin. These chemotherapies induced DNA damage through distinct mechanisms, and it stands to reason that further disruption of DNA break repair may augment the efficacy of these agents. As the ATR (ataxia telangiectasia and Rad3-related) gene responds to DNA single-strand breaks, inhibiting this protein may provide additional benefit to patients. Dr. Pal and colleagues tested such an approach in a randomized phase 2 study of cisplatin and gemcitabine with or without the ATR inhibitor berzosertib.