New Melanoma Drug Uses Tumor-Busting Virus
Source: NBC News, October 2015
The Food and Drug Administration approved a new drug Tuesday that uses a genetically engineered cold sore virus to bust up melanoma skin cancer tumors.
It’s the first drug of its type to get FDA approval. It’s made using a genetically engineered herpes virus — the same kind that causes cold sores — that carries an immune system compound into tumors, causing them to burst apart.
The drug, called Imlygic, doesn’t cure the patient and it has not been shown to help patients live longer, But it provides relief from melanoma, the deadliest form of skin cancer.
The FDA based its approval on a study of 436 people with advanced melanoma that had spread. Visible tumors were injected with the drug.
“The study showed that 16.3 percent of the study participants who received Imlygic experienced a decrease in size of their skin and lymph node lesions, lasting for a minimum of six months," the FDA said in a statement. That compared to 2.1 percent patients who did not get the drug.
“However, 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 FDA noted
Side-effects include fatigue, chills, fever, nausea, flu-like symptoms and pain at the injection site. It can also give patients herpes – the herpes simplex 1 infection that causes cold sores.
Amgen, which makes the drug, says it plans to make it available for melanoma patients within a week.
“Amgen anticipates the average cost of Imlygic therapy to be approximately $65,000," the company said in a statement. Amgen says it wants to work with patients to keep the cost under control as much as possible.
Drugmakers have been under fire for selling drugs at enormous prices, especially drugs that do not cure the diseases they’re meant to treat — especially cancer.
The herpes virus that the drug’s based on is genetically engineered to deliver a compound called granulocyte-macrophage colony-stimulating factor or GM-CSF. It stimulates the immune system and somehow – scientists are not quite sure how — causes tumor cells to burst in a process called lysis.
When they break up, the bits of tumor may stimulate the immune system to attack them, too, and perhaps to hold tiny tumor cells in check for at least a while.
“Melanoma is a serious disease that can advance and spread to other parts of the body, where it becomes difficult to treat," said FDA’s Dr. Karen Midthun, directs the center that approved the drug.
“This approval provides patients and health care providers with a novel treatment for melanoma," she said.
Melanoma is the deadliest form of skin cancer. According to the National Cancer Institute, 74,000 Americans will be diagnosed with melanoma and nearly 10,000 will die from it this year.