Drug combination tests can destroy deadly skin cancer

Dramatic trial results indicate that a combination of two immunotherapy drugs can wipe out the most deadly form of skin cancer even when the disease is advanced.

Of 95 patients given the treatment, more than 60% were still alive after two years and of these a fifth (22%) had no detectable tumours remaining.

A total of 142 patients were randomly allocated either to receive two drugs, nivolumab and ipilimumab, or ipilimumab alone.

The therapies, consisting of lab-made antibodies, are designed to overcome the ability of some cancers to evade the immune system.

Findings from a Phase II US-led trial testing the effectiveness of the drug combination were presented at the annual meeting of the American Association for Cancer Research in New Orleans British expert James Larkin, consultant medical oncologist at the Royal Marsden Hospital, has treated patients with the drugs as part of another on-going trial.

Dr Larkin said: “Both nivolumab and ipilimumab have changed survival expectations in advanced melanoma over the last few years and these latest data show us that combining these two immunotherapies is an effective two-pronged attack against the cancer.

“The overall survival rates observed using the regimen of nivolumab plus ipilimumab are very promising and provide further hope for patients and their families affected by this disease.”

In 2013, around 14,500 people in the UK were diagnosed with melanoma and 2,100 died from the disease.

Melanoma is at the forefront of new immunotherapy approaches to cancer treatment.

The immune system is constantly fighting a battle with cancer, and usually wins. However, sometimes it fails, due to cancers exploiting mechanisms designed to prevent a too-strong immune response harming the body’s own tissues.

The antibody drugs, known as “checkpoint inhibitors”, interrupt two different signalling pathways to take the brakes off the immune system.

Each blocks a separate receptor ‘switch’ on immune system T-cells that weakens the immune response and can be activated by molecules released by tumours. Ipilimumab targets a receptor called CTLA-4 while the newer drug nivolumab homes in on the PD-1 receptor.

Patients taking part in the trial had two common forms of melanoma, one with a ‘normal’ version of the BRAF gene and the other with a mutated version.

A total of 69% of patients from the normal or ‘wild-type’ BRAF group treated with the combination therapy were still alive after two years. For the whole population of combination therapy patients, two-year survival was achieved by 64%.