The US Food and Drug Administration has approved talimogene laherparepvec (brand name Imlygic), the first FDA-approved oncolytic virus therapy, for the treatment of melanoma lesions in the skin and lymph nodes.

“Melanoma is a serious disease that can advance and spread to other parts of the body, where it becomes difficult to treat,” said Karen Midthun, M.D., director of the FDA’s Center for Biologics Evaluation and Research.

“This approval provides patients and health care providers with a novel treatment for melanoma.”

Skin cancer is the most common form of cancer in the United States.

Melanoma, one type of skin cancer, is the leading cause of skin cancer related deaths, and is most often caused by exposure to ultraviolet (UV) light.

According to the National Cancer Institute approximately 74,000 Americans will be diagnosed with melanoma and nearly 10,000 will die from the disease in 2015.

Talimogene laherparepvec, a genetically modified live oncolytic herpes virus therapy, is used to treat melanoma lesions that cannot be removed completely by surgery.

Talimogene laherparepvec is injected directly into the melanoma lesions, where it replicates inside cancer cells and causes the cells to rupture and die. 

A treatment course with talimogene laherparepvec consists of a series of injections into the melanoma lesions.

After the initial injection, a second dose is administered three weeks later, followed by additional doses every two weeks for at least six months, unless other treatment is required or until there are no remaining injectable lesions to treat.

The safety and efficacy of talimogene laherparepvec were evaluated in a multicentre study of 436 participants with metastatic melanoma that could not be surgically removed.

The participants’ melanoma lesions in the skin and lymph nodes were treated with talimogene laherparepvec or a comparator therapy for at least six months, or until there were no remaining injectable lesions.

The study showed that 16.3 percent of the study participants who received talimogene laherparepvec experienced a decrease in size of their skin and lymph node lesions, lasting for a minimum of six months, compared to 2.1 percent of the study participants receiving the comparator therapy.

However, talimogene laherparepvec has not been shown to improve overall survival or to have an effect on melanoma that has spread to the brain, bone, liver, lungs, or other internal organs. 

The most common side effects observed in clinical study participants were fatigue, chills, fever, nausea, flu-like symptoms and pain at the injection site.

Because talimogene laherparepvec is a modified live oncolytic herpes virus therapy, herpes virus infection can also occur.

Given this, talimogene laherparepvec should not be given to individuals with suppressed immune systems or who are pregnant.

Imlygic is manufactured by BioVex Inc., a subsidiary of Amgen Inc., based in Thousand Oaks, California.

Source: FDA