Rutgers Cancer Institute scientist leads phase III trial of FDA-approved viral melanoma therapy

Oct 29 2015

The U.S. Food and Drug Administration has approved a viral melanoma therapy that was the focus of a phase III clinical trial led by Rutgers Cancer Institute of New Jersey Associate Director for Clinical Science and Chief Surgical Officer Howard L. Kaufman, MD, FACS.

Talimogene laherparepvec (T-VEC) is a genetically modified herpes simplex virus (type 1) that is now approved for the treatment of recurrent melanoma that is unresectable in patients who have had initial surgery. This oncolytic immunotherapy is injected directly into tumors and is designed to replicate and produce a protein known as GM-CSF (granulocyte-macrophage colony-stimulating factor) that stimulates the immune system. The virus does not replicate in normal tissue. T-VEC causes tumors to rupture and die, a process which releases tumor-derived antigens, which along with GM-CSF may promote an anti-tumor response. However, the exact mechanism of action is unknown and is further being investigated.

T-VEC's action was validated through a phase III, multicenter, open-label, randomized clinical trial known as OPTiM, which compared T-VEC to GM-CSF in patients with advanced melanoma that was not able to be removed surgically. The aim of the study was to determine durable response rate, defined as the percentage of patients with a complete or partial response maintained continuously for at least six months. Out of 436 patients enrolled in the study, 16.3 percent treated with T-VEC achieved a durable response compared to 2.1 percent treated with GM-CSF. Of those who had a durable response, 29.1 percent had a complete response, while 70.8 percent had a partial response.

Dr. Kaufman was the study's lead investigator. "Advanced melanoma remains a complex disease to treat, requiring the use of several modalities over the course of a patient's therapeutic journey. As an oncolytic viral therapy, T-VEC has a unique approach, and provides another option for treating eligible patients with unresectable disease that has recurred after initial surgery," notes Kaufman, who is also a professor of both surgery and medicine at Rutgers Robert Wood Johnson Medical School and the president of the Society for Immunotherapy of Cancer.

"While we may not cure every case of melanoma with these types of immunotherapies, treatments such as T-VEC are enabling us to better manage the disease as if it were a chronic illness like diabetes," adds Kaufman. He notes next steps are to combine T-VEC with a new class of drugs known as 'checkpoint inhibitors' that also produce an immune response in the body by taking the breaks off the immune system and enabling it to fight off cancer. Such study is underway currently at Rutgers Cancer Institute.