Combination immunotherapy helps overcome melanoma treatment resistance

Early data from a Phase 2 clinical trial show a combination of immunotherapy medications can activate a robust immune response and help overcome treatment resistance in patients with refractory melanoma.

The University of Cincinnati Cancer Center’s Trisha Wise-Draper, MD, Ph.D., will present a late-breaking abstract detailing the trial results at the Society for Immunotherapy of Cancer 40th Anniversary Annual Meeting Nov. 7.

Oncolytic viruses are specially engineered to infect and destroy cancer cells. The Phase 2 IGNYTE trial is testing RP1, a genetically modified herpes simplex type 1 virus designed to directly destroy tumors and generate a robust antitumor immune response.

The trial is testing RP1 in combination with nivolumab, an immunotherapy drug that targets PD-1 protein receptors on tumors to help the body’s own immune system identify and attack cancer cells.

Reviewing data from 140 patients enrolled in the trial, Wise-Draper and colleagues found the combination of RP1 and nivolumab led to increased immune response, immune cell infiltration and activation within tumors in patients who had not previously responded to immunotherapy, indicating RP1 helps overcome treatment resistance.

“The trial itself was positive in that approximately one-third of the patients with refractory melanoma will respond to this combination, and responses are durable,” said Wise-Draper, professor of medicine in the Division of Hematology/Oncology, section head of medical oncology, co-leader of the Head and Neck Experimental Advancement Laboratory in UC’s College of Medicine, and deputy director of UC’s Office of Clinical Research. “This is a promising combination that is well tolerated for patients with PD1 refractory melanoma.”

Other abstract co-authors include Praveen Bommareddy, Caroline Robert, Joseph J. Sacco, Gino K. In, Eva Muñoz Couselo, Dirk Schadendorf, Jiaxin Niu, Georgia M. Beasley, Bartosz Chmielowski, Mohammed M. Milhem, Tawnya Lynn Bowles, Katy K. Tsai, Céleste Lebbé, Caroline Gaudy-Marqueste, Adel Samson, Junhong Zhu, Marcus Viana, Chris Tucci, Bhavna Paratala, Jeannie W. Hou and Michael K. Wong.