Cold sore treats cancer

A genetically engineered cold sore virus has been used to specifically target and burst cancer cells in patients suffering cancers of the head and neck.

The virus – the herpes simplex virus known as OncoVEX – was injected into 17 patients’ cancer-affected lymph nodes in up to four doses: the patients were also treated with radiotherapy and chemotherapy. Tumour shrinkage in 14 patients was seen, and in surgery to remove their lymph nodes, 93% of patients had no traces of residual cancer.

“This trial showed for the first time that these oncolytic viruses can be safely used in combination with other cancer treatments given with the intention of curing patients,” said principal investigator Dr Kevin Harrington from the ICR and The Royal Marsden Foundation Trust.

The virus multiplies inside cancer cells and bursts, killing the tumour cells. It leaves healthy cells untouched, and by expressing a human protein, it helps to stimulate the patients’ immune systems. Side effects were mild to moderate, with most – except fatigue and fever – thought to be associated with chemotherapy and radiotherapy.

After an average follow-up time of 29 months, 82% of patients had not succumbed to the disease, and only two of 13 who received virus treatment at high dose relapsed.

“Around 35 to 55% of patients given the standard chemotherapy and radiotherapy treatments typically relapse within two years, so these results compare very favourably,” said Harrington, “This was a small study so the results should be interpreted with caution.”

The drug will now be taken into a large scale Phase III trial – the first of its kind to combine virus therapy with chemoradiation.