“These data are solid, showing a 7-month improvement in overall survival in patients with stable disease or better after first-line chemotherapy. This is roughly a 50% improvement in survival, which is clinically meaningful. Also, progression-free survival was significantly increased with maintenance avelumab,” said Jonathan E. Rosenberg, MD, of Memorial Sloan Kettering Cancer Center in New York. “We still need better choices for patients with disease progression after first-line chemotherapy, but these patients were not enrolled in this trial,” he added.

Jonathan E. Rosenberg, MD

Dr. Rosenberg noted that a smaller phase II trial showed a progression-free survival benefit for maintenance pembrolizu­mab in advanced urothelial cancer with at least stable disease after chemotherapy, but the small sample size precluded showing a survival benefit.¹ “This earlier trial suggested a benefit for maintenance pembrolizumab,” he noted.

The toxicity data were relatively similar to those seen for other immune checkpoint inhibitors, he continued. “Avelumab can cause infusion reactions, but premedication with [acetaminophen] lessens this,” he said.

“Right now, we have five drugs approved for patients who have disease progression after platinum chemotherapy. If the FDA approves avelumab, it will be the first drug to be approved as maintenance therapy in patients with stable disease or better after chemotherapy. Taken together with evidence in patients with disease progression after chemotherapy, nearly all patients with advanced urothelial cancer will likely be treated with an immune checkpoint inhibitor following completion of front-line chemotherapy,” Dr. Rosenberg commented.

DISCLOSURE: Dr. Rosenberg has served in a consulting or advisory role for Astellas, AstraZeneca, Bristol-Myers Squibb, EMD Serono, Pfizer, Roche/Genentech, Merck, and Seattle Genetics; has received research support from Astellas, AstraZeneca, Seattle Genetics, Genentech/Roche, Incyte, and Novartis: and held stock in Illumina.

REFERENCE

1. Galsky MD, et al: Randomized double-blind phase II study of maintenance pembrolizumab vs placebo after first-line chemotherapy in patients with metastatic urothelial cancer. 2019 ASCO Annual Meeting. Abstract 4504. Presented June 3, 2019.