Real-world outcomes of pembrolizumab for platinum-refractory advanced urothelial carcinoma: Efficacy, safety, and evidence for trial-unfit patients.

Pembrolizumab, monoclonal antibody targeting programmed cell death 1, is widely used for platinum-refractory urothelial carcinoma (UC) patients. Although the survival benefit of pembrolizumab was proven in the well-designed phase III trial, these data represent only a part of patients due to strictly defined eligibility criteria. The patients' characteristics in the clinical practice are much more heterogenous than those of trial participants. The real-world experience is useful to validate the trial result and find suitable candidates for the treatment. Similarly, real-world data plays a significant role in addressing the efficacy and safety of special populations, such as poor performance status or older patients. This review summarizes the real-world evidence on pembrolizumab for platinum-refractory UCs and discusses the clinical risk factors and efficacy for trial-ineligible patients.