A genetically engineered herpes virus can stop the progression of skin cancer by killing cancer cells and sparking the immune system into action against tumors, according to a recent clinical trial by The Institute of Cancer Research, London.
Researchers randomized 436 patients with aggressive, inoperable malignant melanoma to receive either an injection of the viral therapy, called Talimogene Laherparepvec, or a control immunotherapy.
Of the group given Talimogene Laherparepvec, or T-VEC, 16.3% showed a durable treatment response of more than six months, compared with 2.1% given the control treatment. Some patients also had a response extending past three years, a mark oncologists often use as a proxy for cure in immunotherapy.
Responses to the treatment were most pronounced in patients with less advanced cancers, and those who had yet to receive any treatment, making the potential benefits of T-VEC as a first-line treatment for metastatic melanoma which cannot be surgically removed.
T-VEC is a modified form of herpes simplex virus type-1, which multiplies inside cancer cells and bursts them from within. It has been genetically engineered to produce a molecule called GM-CSF, which stimulates the immune system to attack and destroy the tumor.