On 27 October 2015, the US Food and Drug Administration (FDA) approved talimogene laherparepvec (Imlygic), the first FDA-approved oncolytic virus therapy, for the treatment of melanoma lesions in the skin and lymph nodes.
Imlygic, a genetically modified live oncolytic herpes virus therapy, is used to treat melanoma lesions that cannot be removed completely by surgery. Imlygic 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 Imlygic 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 Imlygic were evaluated in a multicenter 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 Imlygic or a comparator therapy for at least six months, or until there were no remaining injectable lesions.
The study showed that 16.3% 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, compared to 2.1% of the study participants receiving the comparator therapy.
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 most common side effects observed in clinical study participants were fatigue, chills, fever, nausea, flu-like symptoms and pain at the injection site.
Because Imlygic is a modified live oncolytic herpes virus therapy, herpes virus infection can also occur. Given this, Imlygic 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.