Irish pharmaceutical company Elan posted a greater-than-expected loss in its third-quarter results, and news that its Tysabri drug was effective in a clinical trial in Crohn’s disease patients could not outweigh suggestions that doctors are wary of prescribing the drug for multiple sclerosis.

The drugmaker reported a third-quarter net loss of $117 million, an increase from the $67 million reported the same time last year and worse than analysts' expectations, on revenues down nearly 10% at $123 million.

Elan said the decline in sales resulted from temporary supply problems for its Maxipime (cefepime) antibiotic, which dipped to $93.5 million in sales from $114 million a year earlier. Tysabri (natalizumab), which was re-launched for MS in July, contributed $8 million.

Tysabri has now been returned to the market in a number of European countries and the USA, having been withdrawn last year over links to a rare but life-threatening adverse reaction affecting the brain. Some analysts had hoped it would make a swift contribution to Elan’s fortunes in 2006, bringing in upwards of $75 million.

'We are encouraged by the initial results in the re-launch of Tysabri for MS in the US market and the launch in the European markets,' said chief executive Kelly Martin.

But shares in Elan dipped 2.4% yesterday to 12.10 euros yesterday on the results of a survey indicating that the drug will be used in less than 1% of patients with MS in the USA, and that only 47 out of 8,500 patients who had been on the drug had re-started treatment, even though 700 had discussed it. News of the results sparked another half-point drop in trading this morning.

Costs of developing Elan’s Alzheimer’s disease treatments contributed to the loss, with analysts cited by Bloomberg noting that there is a chance the lead compound in this programme could be filed as early as the second half of 2007.

Tysabri filing in Crohn’s disease this year

There was better news for Elan though when it reported clinical data indicating that Tysabri is effective in maintaining remission in Crohn’s disease patients for more than two years.

The results of the 90-patient study, reported at the at 14th United European Gastroenterology Week, showed that 93% of patients remained in remission after one year’s treatment, dropping to 86% after a second year. Elan said it would be able to file for approval of Tysabri in Crohn’s by the end of the year.

The results were particularly remarkable as 22 of the patients enrolled into the study had been resistant to treatment with Johnson & Johnson’s TNF blocker Remicade (infliximab). Even in this resistant population, the remission rate was 82% after two years.

"What is truly exciting is that patients who enter remission on Tysabri may remain in remission in the long-term without loss of efficacy over time," said Dr Remo Panaccione, director of the inflammatory bowel disease clinic at the University of Calgary in Canada.