Herpes Virus Offers Hope Over Skin Cancer

Scientists are hoping a new treatment for skin cancer, found to completely destroy tumours in some patients, could be made available within a year.

The Phase III trial treatment, which comes from a genetic modification of the cold sore virus, has been tried on patients suffering from inoperable tumours.

It involved directly targeting cancer cells through an immunotherapy approach that uses the body's own defences to fight the disease and halt tumour growth.

One in 10 patients of the 26% who were responsive to the herpes virus treatment - known as T-Vec - found their tumours vanished completely.

Another 16% of responding patients saw a "partial remission" that more than halved the size of their tumour.

A Phase III trial is the last step before a new medicine can be licensed and made available to patients.

Professor Kevin Harrington, from the Institute of Cancer Research in London, led the trials which were held in the UK, US, Canada and South Africa.

Professor Harrington said: "It's not an exaggeration to say this is a first-in-class agent, an entirely new type of anti-cancer treatment.

"There will have to be discussions about cost effectiveness but we hope to see this agent receive approval in about the next 12 months, making it possible to prescribe it for cancer.

"There is increasing excitement over the use of viral treatments like T-Vec for cancer, because they can launch a two-pronged attack on tumours - both killing cancer cells directly and marshalling the immune system against them.

"And because viral treatment can target cancer cells specifically, it tends to have fewer side-effects than traditional chemotherapy or some of the other new immunotherapies."

The T-Vec treatment contains the same herpes simplex type-1 virus that causes cold sores, but it has been genetically engineered to make it harmless to patients but lethal to cancer.

The virus cannot multiply in healthy skin cells but finds fertile ground for growth in tumour cells, expanding to such an extent that it literally explodes out of the cancer cells, thereby destroying them.

It is not clear how long it will keep patients clear of cancer but some patients have remained in remission for as long as three years.

Findings from the trial, which included 295 of 436 patients who had aggressive, inoperable malignant melanoma, were reported in the Journal of Clinical Oncology .