Regeneron Pharmaceuticals, Inc. and SillaJen, Inc. announced a new clinical and supply agreement for a Phase 1b dose-escalation study in renal cell carcinoma, or kidney cancer. The study will evaluate Regeneron's PD-1 inhibitor, REGN2810, in combination with SillaJen's oncolytic vaccinia virus, Pexa-Vec, in patients with previously treated metastatic or unresectable renal cell carcinoma. The open-label trial is expected to begin later this year, and is designed to evaulate the safety and efficacy of REGN2810 in combination with Pexa-Vec compared to treatment with REGN2810 as monotherapy.

The study will initially open in Korea, with expansion to sites in the U.S. Renal cell carcinoma is the most common type of kidney cancer in adults, and accounts for approximately three percent of adult malignancies and 90% to 95% of neoplasms arising from the kidney. Pexa-Vec has been shown to increase inflammation in the tumor micro-environment and potentially reverse the immunosuppressive microenvironment by activating T-cell mediated anti-tumor immune response. This may help "prime" the tumor by increasing sensitivity to anti-PD-1 treatment, such as REGN2180.

Under the terms of the agreement, the trial will be solely conducted and funded by SillaJen based upon a mutually developed study design," and Regeneron will provide REGN2810. Regeneron, in collaboration with Sanofi, is developing REGN2810 both alone and in combination with other therapies for the treatment of various cancers.