Pembrolizumab and Docetaxel or Gemcitabine Hydrochloride in Treating Patients Urothelial Cancer

This phase I trial studies the side effects and best dose of pembrolizumab when given together with docetaxel or gemcitabine hydrochloride in treating patients with previously treated urothelial cancer that has spread to other places in the body and usually cannot be cured or controlled with treatment (advanced) or that has spread from the primary site (place where it started) to other places in the body (metastatic). Monoclonal antibodies, such as pembrolizumab, may block tumor growth in different ways by targeting certain cells. Drugs used in chemotherapy, such as docetaxel and gemcitabine hydrochloride, work in different ways to stop the growth of tumor cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Giving pembrolizumab together with docetaxel or gemcitabine hydrochloride may be a better treatment for urothelial cancer.