Persistent clinical benefit was seen among a small group of patients with metastatic renal cell carcinoma (RCC) who had to discontinue therapy with the PD-1 inhibitor nivolumab (Opdivo) because of immune-related adverse events, according to the results of a study presented at a press conference ahead of the Genitourinary Cancers Symposium in Orlando, FL.
“Responders to PD-1/PD-L1 targeted therapy can have persistent clinical benefit despite treatment discontinuation for immune-related adverse events,” researcher Rana R. McKay, MD, of University of California San Diego School of Medicine, said during the press conference.
According to Dr. McKay, PD-1/PD-L1 inhibitors are associated with a wide variety of immune-related side effects, which are thought to occur because of immune system activation. With this study, she and her colleagues examined the outcomes of patients with metastatic RCC who responded to immunotherapy treatment but had to stop therapy because of side effects. The study included 19 patients with metastatic RCC who were treated with nivolumab.
“The patients in this cohort experienced a wide spectrum of adverse events affecting differing organ systems. These included pneumonitis, myositis, nephritis, hepatitis, pericarditis, and myocarditis, just to list a few,” Dr. McKay explained.
Patients were classified as durable responders if they were free from progression for more than 6 months after treatment discontinuation. Patients were classified as immediate progressors if they progressed within 4 months of discontinuation.
Of the 19 patients, 63% were treated with nivolumab monotherapy. The overall median duration of therapy was 5.5 months. One patient had a complete response, seven patients had partial response, and one had stable disease.