High-dose Interleukin-2 Continues To Be Safe, Effective First-Line mRCC Treatment

MIAMI – High-dose interleukin-2 (HD IL-2) continues to have a favorable safety profile compared with data in the original package insert and remains an effective frontline treatment for eligible patients with metastatic renal cell carcinoma (mRCC), a study presented at the 14^th International Kidney Cancer Symposium 2015 (IKCS) has shown.¹

Although HD IL-2 is approved for use as first-line therapy for patients with mRCC by the U.S. Food and Drug Administration, the data supporting its use dates back to the 1990’s.

“Earlier reported data from Proleukin-treated mRCC patients may have underestimated survival benefit related to HD IL-2,” Joseph I. Clark, MD of Beth Israel Deaconess Medical Center in Boston, MA, said during the poster presentation.

Therefore, researchers designed the PROCLAIM registry to evaluate contemporary survival outcomes and interactions with prior targeted therapies.

For the analysis, researchers analyzed data from 352 patients with mRCC who received at least 1 dose of IL-2. Results showed that the median overall survival of stable disease patients was not reached (95% CI, 34.82 – NE), suggesting that stable disease is clinically relevant. There was a 1-, 2- and 3-year survival of 78%, 61%, and 52%, respectively.

In those who had received prior targeted therapy, the median overall survival was 22.13 months (95% CI, 13.08 – NE), but median overall survival had not yet been reached in those who had not received prior targeted therapy (95% CI, 34.82 – NE)

“Patients with stable disease after HD IL-2 therapy may not benefit from receiving follow-up targeted therapy,” Dr. Clark said.

In regard to safety, the authors noted 4 treatment-related deaths among the 352 patients.

“HD IL-2 immunotherapy has long been an advocated rational approach for eligible patients with mRCC, and carries the potential benefit of inducing stable and durable remission that lasts decades,” Dr. Clark concluded. “The appropriate and optimum sequencing of HD IL-2 with current and future targeted therapies and immunotherapies needs to be established.”

Reference

1. Clark JI, Morse MA, Wong MKK, et al. Durability of responses in patients with metastatic renal cell carcinoma treated with high dose interleukin- 2 (HD IL-2) [abstract]. BJU Int. 2015. doi: 10.1111/bju.13365.