The U.S. Food and Drug Administration (FDA) has just approved Imlygic (talimogene laherparepvec), making it the first FDA-approved oncolytic virus therapy in combating deadly skin cancer.
The genetically engineered cold sore virus made by Amgen Inc. is an injectable drug, and will be initially only used on melanomas that cannot be removed surgically. The company said a single course would cost about $65,000 depending on the length of the treatment.
Karen Midthun, M.D., who is the director of the FDA’s Center for Biologics Evaluation and Research, said in a statement: “Melanoma is a serious disease that can advance and spread to other parts of the body, where it becomes difficult to treat,” adding:
‘This approval provides patients and health care providers with a novel treatment for melanoma.’
The most common type of cancer in the U.S. is skin cancer, with melanoma being the leading cause of skin cancer-related deaths. Excessive exposure to ultraviolet (UV) light is the most common cause of melanomas. According to the FDA, there will be approximately 74,000 Americans diagnosed with melanoma, with almost 10,000 of them dying in 2015 alone.
Imlygic is a genetically modified live oncolytic herpes virus therapy, and will be injected directly into the melanoma lesions, where it replicates inside cancer cells until the membranes, or outer layers, of the cancer cells burst. While this is happening, the gene snippet produces a protein that stimulates an immune response that kills the melanoma cells in the tumor and elsewhere in the body.
According to the FDA, the treatment will consist of a series of injections. After the first treatment, a second injection will be administered three weeks later, and then there will be additional treatments every two weeks for at least six months, unless other treatment is required or until there are no remaining injectable lesions to treat.
Even though it is being seen as a “groundbreaking drug,” the FDA cautioned: “Imlygic 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 clinical study participants found that fatigue, chills, fever, nausea, flu-like symptoms, and pain at the injection site were the most common side effects. A herpes virus infection can also occur, as the Imlygic drug is a modified live oncolytic herpes virus therapy. Knowing this, people who are pregnant or individuals who have suppressed immune systems should not be given the treatment.