A drug initially developed to treat some types of cancer now appears to help people suffering from multiple sclerosis (MS), a study said.

The drug, alemtuzumab, proved effective in patient trials at reducing relapses -- a key feature of MS which sees symptoms appear sporadically.

In one trial, patients who received the drug "were nearly half as likely to relapse within two years than those who received interferon", the most commonly-used MS drug, said a statement by the Lancet medical journal, which published the research. A second trial had similar results.

The outcome "offers the prospect of substantial improvement in quality of life and a better future for thousands of people with MS," said Alastair Compston from the University of Cambridge, principal investigator on both studies.

Many MS patients already use alemtuzumab, even though it has not been licensed for this purpose.

--AFP story and graphic