Increased sales of its multiple sclerosis blockbuster Tysabri has helped drugmaker Elan compensate for falling demand for two of its infection treatments. However, losses at the group still widened, due to higher spending on research and development and new restructuring charges.

For the first quarter of 2009, pre-tax losses grew by 6 per cent to $88.6m on revenues that rose 14 per cent to $215m, after the Irish company took $38m in charges. The loss per share rose from 0.18 cents to 0.22 cents.