Biogen Idec has posted fourth-quarter results which reveal a 2.7% slip in profits, though revenues rose 6.9% thanks to continued strong growth for its multiple sclerosis blockbusters Avonex and Tysabri.

Net income came in at $292.1 million, and the fall was principally due to increased costs ahead of upcoming product launches. Most notable of those should be for the company's MS drug, which will be called Tecfidera (dimethyl fumarate) and was formerly known as BG-12.

The US Food and Drug Administration is expected to give its verdict on the pill in March and Biogen hopes to be in a position to launch in the second quarter. Analysts believe Tecfidera will be a blockbuster and may have advantages to MS tablets already on the market, namely Novartis' Gilenya (fingolimod) and Sanofi's Aubagio (teriflunomide).

Back to the figures and Biogen's sales reached $1.42 billion, driven by Avonex (interferon beta-1a), which rose 7.1% to $753.2 million. Tysabri (natalizumab), partnered with Ireland’s Elan Corp, contributed $295.2 million to the company's coffers (+9.6%) while global sales were up 14% to $433 million; as of the end of December, some 72,700 patients were on Tysabri therapy worldwide.

The rheumatoid arthritis and cancer drug Rituxan (rituximab), partnered with Roche, brought in $281 million, up 9%, while Fampyra, a prolonged-release tablet formulation of fampridine to improve walking in adults with MS licensed from Acorda Therapeutics, edged up 0.7% to $10.5 million; sales of the psoriasis treatment Fumaderm (fumaric acid) climbed 16.5% to $15.8 million.

Chief executive George Scangos said that "we are poised to begin what we expect will be a remarkable period of growth", led by Tecfidera, a longer-acting version of Avonex, and two haemophilia drugs. He added that "we appreciate the excitement that MS and haemophilia patients have expressed to us about these candidates, and our teams are well prepared to support the launches".