Ireland’s Elan Corp has reported a loss for the fourth quarter, but enjoyed healthy sales of its multiple sclerosis treatment Tysabri.

Net loss came in at $57.7 million, compared with income of $169.5 million in the like, year-earlier period when the figures benefited from a $234 million tax benefit. while revenues climbed 11% to $300.0 million. The rise was driven by Tysabri (natalizumab) and global sales of the drug, which is marketed with Biogen Idec, reached $296.3 million, up 37%.

Elan’s share of the Tysabri revenues increased 32% to $200.5 million. As for the Dublin-headquartered company’s other products, the antibiotic Maxipime (cefepime), which was ravaged during the year by generic competition, brought in $3.8 million for the quarter, up 23%.

Azactam (aztreonam), another antibiotic, increased 15% to $23.9 million, while sales for the severe pain treatment Prialt (ziconotide) fell 30% to $3.1 million. Elan noted that “revenues from this product have not met expectations” and recorded an impairment charge of $30.6 million relating to the Prialt intangible asset.

Sales at the Elan Drug Technologies business fell 24% to $68.1 million, as manufacturing revenues and royalties from the likes of Abbott Laboratories’ cholesterol drug TriCor (fenofibrate; $17.0 million) and King Pharmaceuticals’ muscle relaxant Skelaxin (metaxalone; $9.1 million) fell from the fourth quarter of 2008 .

Chief financial officer Shane Cooke said that “for 2010, we expect to report operating profits before other charges or gains for the first time in several years, driven by our continued growth in revenue and reduced operating expenses”. Ian Hunter an analyst at Goodbody’s in Dublin, described the results as solid and forecast 2010 operating profits of $87.4 million, although he noted that a planned additional trial of Tysabri will be long and costly.