ASCO 2021: 5-Year Update on Pembrolizumab for Advanced Urothelial Cancer
Posted: Tuesday, June 15, 2021
According to Joaquim Bellmunt, MD, PhD, of Harvard Medical School, Boston, and colleagues, pembrolizumab appeared to sustain deeper and more durable responses among patients with urothelial cancer than chemotherapy. Based on the updated 5-year follow-up of the phase III KEYNOTE-045 trial, presented during the 2021 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract 4532), pembrolizumab maintained a “clinically meaningful overall survival benefit versus chemotherapy” in patients with locally advanced or metastatic urothelial cancer that had progressed during or after platinum-based chemotherapy.
The research team randomly assigned 542 patients with urothelial carcinoma to receive pembrolizumab or investigator’s choice of paclitaxel, docetaxel, or vinflunine. The median overall survival was longer among patients treated with pembrolizumab (10.1 months) versus chemotherapy (7.2 months). Among patients who achieved complete or partial responses, the median overall survival was not reached with pembrolizumab versus 16.4 months with chemotherapy. At 48 months, the overall survival rates were 16.7% with pembrolizumab and 10.1% with chemotherapy. The positive trend in overall survival with pembrolizumab continued at 60 months (14.9 months vs. 8.7 months, respectively). The overall survival benefit associated with pembrolizumab was maintained regardless of age, prior therapy, liver metastases, baseline hemoglobin, histology, risk factors, and chemotherapy choice.
Among patients who responded to immunotherapy, the median duration of response was longer with pembrolizumab than chemotherapy (29.7 vs. 4.4 months). A greater proportion of patients treated with pembrolizumab than chemotherapy experienced responses lasting at least 48 months (40.9% vs. 28.3%) and at least 60 months (32.8% vs. 28.3%).
Treatment-related adverse events of any grade were reported in fewer patients treated with pembrolizumab than chemotherapy (62.0% vs. 90.6%, respectively). Reports of severe adverse events were also fewer with pembrolizumab versus chemotherapy (16.9% vs. 90.6%).
Disclosure: For full disclosures of the study authors, visit coi.asco.org.