Herpes simplex virus, shown magnified

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Herpes simplex virus, shown magnified here, is genetically modified to create talimogene laherparepvec (T-VEC). This immunotherapy drug has been effective in treating patients with advanced-stage melanoma, who have demonstrated a significant improvement in survival rates.

Melanoma, a skin cancer, is one of the deadliest of cancers, killing one person every hour. Just a decade ago, patients with an advanced case of it were given eight months or less to live. But now there’s a powerful weapon in the fight against melanoma: the immunotherapy drug talimogene laherparepvec, or T-VEC. It’s part of a new class of therapies made from an unlikely source: viruses.

T-VEC was the subject of a Phase III clinical trial led by Howard Kaufman, an associate director for clinical science and chief surgical officer at Rutgers Cancer Institute of New Jersey. Patients with advanced-stage melanoma who were treated with T-VEC had a significant improvement in durable response rate and improved survival. 

Kaufman presented this data to the Food and Drug Administration in April 2015 and T-VEC was approved in October. “This is great news for patients,” says Kaufman. “Advanced melanoma is a complex disease to treat because it can advance and spread to other parts of the body. This therapy offers us another option for treating serious disease that recurs after surgery.”

Kaufman and his laboratory team are attempting to develop immunotherapies, working primarily with viruses. Cancer-focused immunotherapy is the groundbreaking new frontier of treatment. It works by activating the body’s own immune system to fight disease. And unlike chemotherapy, immunotherapy has few side effects, which often include fever, fatigue, nausea, and pain at the injection site.

T-VEC is a genetically modified form of herpes simplex, the virus that causes cold sores. The virus-causing genes are deactivated in the drug, making it safer. Many people regard viruses (from the Latin virus, meaning toxin or poison) as harmful. Kaufman, who is also a professor of surgery at Robert Wood Johnson Medical School, thinks differently. “Viruses represent a new class of drug that can do a great deal of good,” he says. “Used alone or in combination with other drugs, they have the potential to save lives.”

The FDA designated T-VEC a “first-in-class” drug—meaning that it uses a unique mechanism of action for treating a medical condition. “It fights cancer through two mechanisms,” says Kaufman. “It’s injected directly into a tumor, where it replicates. It does not replicate in normal cells. The cancer cells are destroyed, releasing more cancer-fighting viruses into the body. T-VEC also boosts the immune system by activating T-cells, which kill tumors. The response rate is fairly constant across several studies in melanoma.”

The incidence of melanoma has increased since the mid-1970s, most likely because of increased UV radiation exposure. Tanning is linked to melanoma, and indoor tanning may increase this risk by up to 59 percent. “With these new therapies, we’re encouraged that the mortality from melanoma will drop,” says Kaufman.

Kaufman, who recently became the president of the Society for Immunotherapy of Cancer, is proud of his outcomes. “The responses we’re seeing are long-lasting, up to 10 years,” he says. “While we may not cure every case of melanoma, we’re turning it into a chronic,  manageable disease, like diabetes.”