Biogen Idec saw its profit nearly triple in the first quarter of the year, overshooting Wall Street expectations, but sales were slightly under par on slow growth of its veteran multiple sclerosis drug, Avonex.

First-quarter sales reached $611.2 million, with growth of 4% a little on the slow side after disappointing sales of Avonex, up just 5% to $393 million, on weaker demand for MS drugs during the period.

The company generated net income of $123 million, or $0.36 a share, compared to $43.5 million, or $0.12 per share, a year ago, when it was struggling to overcome the market removal of its hotly-anticipated MS drug Tysabri (natalizumab), which it sells with Irish drugmaker Elan, after a few patients developed a rare but potentially-fatal central nervous system disorder.

Tysabri's withdrawal in February last year came as a severe blow to both firms, which were pinning their hopes on the drug for future growth, given that it had been tipped to achieve peak sales of $2 to $3 billion by 2007. But things look to be on the way up again. After extensive evaluation of safety data, a Food and Drug Administration advisory panel has recommended permitting sales of the drug to resume with a revised label and other restrictions to address risks. A decision is expected by the end of June.

The company confirmed its earlier expectations for full-year earnings, which are targeted at $1.95 to $2.10 per share, excluding stock option expenses and one-time items.