Amgen said results were positive in a Phase II clinical trial evaluating Imlygic (talimogene laherparepvec) in combination with Yervoy (ipilimumab) in treating unresectable stage IIIb-IV melanoma versus treatment with Yervoy alone.
The trial showed that the combination treatment more than doubled the objective response rate (ORR) in patients with tumors. Of the patients who received Imlygic plus Yervoy, 35 percent saw tumor reductions of at least 50 percent. Only 14 percent of the Yervoy patients saw reductions.
"Metastatic melanoma continues to be one of the most difficult-to-treat and aggressive cancers," Dr. Jason Chesney, study investigator and acting director of the James Graham Brown Cancer Center, University of Louisville, said in a release. "The results from this study demonstrate the potential of combining the complementary mechanisms of action of an oncolytic viral immunotherapy and a checkpoint inhibitor to enhance anti-tumor effect in patients with advanced melanoma."
One hundred and ninety-eight patients participated in the randomized study, with 98 in the Imlygic plus Yervoy group and 100 in the Yervoy group. Imlygic, a genetically modified herpes simplex type 1 virus, was injected directly into the tumors. In combination with the immune checkpoint inhibitor Yervoy, the patients saw a median progression-free survival (PFS) of 8.2 months. The patients in the Yervoy alone group saw a median PFS of 6.4 months
"Patients with metastatic melanoma are in need of innovative, effective treatment options that can improve response rates and help prevent disease recurrence," Amgen Executive Vice President of Research and Development Sean Harper said in the release. "These are the first randomized, controlled, Phase 2 data demonstrating clear efficacy and safety of an oncolytic virus with a checkpoint inhibitor. We are excited to be exploring Imlygic with PD-1 and PDL-1 checkpoint inhibitors as well."