Immunotherapy Combinations for Renal Cell Carcinoma Offer Promise, Challenges
Pivotal phase 3 trials show promising top-line findings for patients with metastatic renal cell carcinoma.
CheckMate-025 Trial Shows Promising Front-line Results
Dr. Jonasch discussed current expectations for pivotal phase 3 trials involving immune-based therapies, including CheckMate-025, which compared nivolumab versus everolimus in previously treated patients with advanced metastatic RCC.
That trial was stopped early when an assessment conducted by the independent Data Monitoring Committee in July 2015 concluded that the study met its endpoint when top-line findings demonstrated superior OS in patients receiving nivolumab compared to controls.4
Full data from the CheckMate-025 trial have not been released, but the panelists were optimistic given the results. “If this were to be positive, it would be the first new immuno-oncologic agent in RCC,” said Dr. Jonasch.
He said that the primary endpoint of the CheckMate-025 study was OS, which made it distinct from most of the trials that have been done in RCC. In many RCC trials, progression-free survival has been the primary endpoint.
“What we're expecting is that these profound and prolonged responses that we have seen in a subset of individuals might be borne out in this situation and we might actually see a prolongation of OS,” he said.
Dr. McDermott pointed out that there are limited data on how these therapies work for previously untreated patients, which creates challenges and opportunities for practicing oncologists.
He said that it is important to offer immunotherapies early in treatment situations because of the small chance of a durable remission that would preclude the need for subsequent treatments.
“People have good options to fall back on and we've seen encouraging median survivals when we've done that sequence of immunotherapy first followed by tyrosine kinase inhibitors,” he said.
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“But in this case...there are very limited data in untreated patients. So while I would want to move early to bring PD-1 up front, if it got FDA approved, I'd like to see a little bit more data.”
He also said that without a biomarker that can determine who should be treated in a given setting; it may prove difficult to get FDA approval for a single agent anti-PD-1 drug in RCC. “We're still several years away from a predictive marker,” he said.