London, Aug 26 (IANS) A pill that retards the spread of advanced skin cancer is showing 'remarkable' results in early trials.

The experimental drug helped shrink tumours in 80 percent of the people treated with it.

The drug PLX4032 inhibits a 'faulty' gene that activates a protein which drives cell division and hence tumour growth, reports the Telegraph.

Of 48 patients treated in the American and Australian study who had the faulty 'BRAF' gene, 37 saw their tumours shrink significantly. In three cases, the patients' tumours disappeared altogether.

By comparison, dacarbazine, a chemotherapy drug often given to treat melanoma (skin cancer), only has a response rate of five to 15 percent, according to the New England Journal of Medicine.

Malignant melanoma is the most dangerous form of skin cancer - which is triggered by excessive exposure to sunlight - as it has the potential to spread.

If spotted quickly enough chances of survival are good, but if left unchecked, the outcome is often poor. One out of five die of malignant melanoma annually.

As the BRAF gene is present in between 40 and 60 percent of patients with the disease, the new drug could help thousands.

Paul Chapman from the Memorial Sloan-Kettering Cancer Centre in New York, who led the study, said: 'We have seen many tumours shrink rapidly, and in some patients, quality of life improved dramatically.'

'This is the beginning of personalised medicine in melanoma.'

'We have never seen an 80 percent response rate in melanoma, or in any other solid tumour for that matter, so this is remarkable,' said Chapman.

However, he cautioned: 'The tumour responses induced by PLX4032 are not always long-lasting though, and we don't know if treatment really improves overall survival of melanoma patients.'

A larger clinical trial is now underway to determine if that is the case.