Arthritis drug could help beat deadly skin cancer

Scientists seeking treatments for a deadly type of skin cancer say an existing arthritis drug slows the growth of melanomas and could be combined with a drug being developed by Plexxikon and Swiss drugmaker Roche. In laboratory studies using mice and human cancer cells the researchers found that leflunomide, a generic drug commonly used to treat rheumatoid arthritis, also inhibits the growth of melanomas. If further trials prove successful -- both for leflunomide alone and in combination with Roche and Plexxikon's promising new melanoma drug PLX4032 -- patients could have access to new treatments in three to five years, they said.

Japanese drugmaker Daiichi Sankyo bought Plexxikon for $805 million in March. "This is a really exciting discovery - making use of an existing drug specifically to target melanoma," said Grant Wheeler of Britain's University of East Anglia, who worked on the study with scientists from the Children's Hospital Boston in the United States. Melanomas are tumours of the pigment cells in skin. It is the most aggressive form of skin cancer and affects around 160,000 people worldwide each year. If caught early surgery can be used to remove the tumour but if the cancer returns and spreads there are virtually no good alternative treatments and conventional chemotherapy typically works in only around 10 to 20 per cent of these cases. The British and US scientists began their series of experiments by looking at the effects of various chemical compounds on pigments in frogs and zebrafish.