An experimental treatment for metastatic uveal melanoma may confer lasting benefits, according to findings presented at the 2018 American Society of Clinical Oncology annual meeting.

The novel biotherapeutic, developed by Immunocore Limited, prompts the immune system to find and kill cancer cells carrying the melanoma-associated antigen gp100. In a phase 1 trial, patients given weekly IV infusions of ICMgp100 continued to show a robust tumor response at a median follow up of 19 months. The therapy had an objective response rate of 18% and a 1-year survival rate of 74%.

Approximately 1,500 Americans are diagnosed with uveal melanoma each year, and about half of these cases will progress to metastatic disease. There is no effective treatment for the condition.

“Survival rates in uveal melanoma have remained largely unchanged for decades, and it is difficult to treat once it advances to metastatic disease,” said lead investigator Takami Sato, MD, PhD, a medical oncologist at Thomas Jefferson University’s Kimmel Cancer Center. “These data provide compelling evidence that IMCgp100 may offer hope to this underserved patient population.”

IMCgp100 was granted orphan drug designation by the FDA in 2016 and received a promising innovative medicine designation under UK Early Access to Medicines Scheme in 2017.

The safety profile was favorable, the company reported, with no drug-related instances of discontinuation or death. Some patients experienced itching, fever, fatigue, and hypotension, however.

An ongoing phase 2 trial is evaluating the safety and efficacy of IMCgp100 in 150 people with metastatic uveal melanoma who have failed to respond to other modes of therapy. That trial will likely conclude in September 2019.