Elan Corp of Ireland has announced a major narrowing of its losses for the third quarter boosted by a 43% rise in revenues which in turn is being driven by the take-up of its multiple sclerosis treatment Tysabri.

Net loss decreased 25% to $87.4 million, or $0.19 per share, and revenues reached $176.6 million which benefited from increased take-up of Tysabri (natalizumab). Global sales of the drug, which is marketed in tandem with Biogen Idec, reached $93.3 million, up from $8.1 million in the like, year-earlier period, with Elan booking $63.5 million (from $5.4 million). Tysabri only returned to the market last July after being pulled off on safety concerns in February 2005, and its reintroduction came with restrictions to monitor patients for symptoms of the rare brain disease progressive multifocal leukoencephalopathy.

Some 17,000 patients have been treated since Tysabri was reintroduced, exceeding the 15,000-patient target required to break even, noted Elan chief financial officer Shane Cooke. He added that “continued growth from Tysabri “will drive our return to profitability” and it expects the number of patients taking the therapy to reach 100,000 by the end of 2010.

Of its other products, the antibiotic Maxipime (cefepime) suffered a 27% decline in revenues to $19.2 million as generic competition kicked in, while Azactam (aztreonam), another antibiotic, rose 24% to $20.7 million. That figure is expected to be negatively impacted by generic competition in 2007, although no copycat version has been approved yet. Elan’s manufacturing revenue and royalties increased 12% to $65.1 million.

In terms of pipeline, the firm said that iPhase III trials for AAB-001 (bapineuzumab), a humanised monoclonal antibody for Alzheimer's being developed with Wyeth, will begin by the end of the year, while Phase II trials of a second Alzheimer's compound, ACC-001, have begun.