Pembrolizumab Demonstrates Anti-tumor Activity, Acceptable Safety Profile in Urothelial Cancer

For the treatment of patients with advanced urothelial cancer, pembrolizumab demonstrated anti-tumor activity and an acceptable safety profile, according to a study published in The Lancet Oncology.¹

As part of the non-randomized, multi-cohort, open-label phase 1b KEYNOTE-012 basket trial (ClinicalTrials.gov Identifier: NCT01848834), researchers evaluated data from 33 patients who had histologically or cytologically confirmed locally advanced or metastatic urothelial cancer with at least 1% PD-L1 expression.

To determine the safety and activity of pembrolizumab, researchers administered the drug intravenously every 2 weeks until study termination or until disease progression or toxic effects.

While all observed patients received at least 1 dose of pembrolizumab and were subsequently analyzed for safety, 27 patients were assessed for activity in the full analysis. Three patients discontinued treatment with pembrolizumab due to non-treatment-related adverse events before first post-baseline scan, 2 withdrew before the first post-baseline scan, and 1 had “no measurable disease” at baseline.

Of 33 patients, 6 (18%) experienced fatigue and 4 (12%) experienced peripheral edema. Three patients (9%) experienced 5 serious treatment-related adverse events. While 5 patients (15%) experienced 11 grade 3 treatment-related adverse events, no individual event occurred in more than 1 patient.

Overall response was achieved in 7 patients (26%) among the 27 who were assessed for activity upon median follow-up of 13 months, 3 of which were complete and 4 of which were partial. While there were 4 deaths during the course of the study, the researchers determined that none were related to treatment with pembrolizumab.

The authors concluded that their findings support “ongoing phase 2 and 3 studies of pembrolizumab in this population.”

Reference

1. Plimack ER, Bellmunt J, Gupta S, et al. Safety and activity of pembrolizumab in patients with locally advanced or metastatic urothelial cancer (KEYNOTE-012): a non-randomised, open-label, phase 1b study. Lancet Oncol. 2017 Jan 9. doi: 10.1016/S1470-2045(17)30007-4 [Epub ahead of print]