Elan looks to be facing into another round of trials for its key Crohn's disease treatment, after presenting a relatively unchanged update on previously disappointing trials at a medical conference in the US.

Elan said in July that its Antegren treatment for Crohn's disease (a serious condition of the bowel) had failed to meet expectations in the late stages of trials.

The news, which showed that patients had not noted a significant difference between the effects of Antegren and a placebo after 10 weeks of trial, led to a sharp drop in the company's share price.

Elan did not offer specifics on the week-10 data yesterday, but it reported slightly improved results for week 12.

Merrion Stockbrokers analyst Mr Peter Frawley said however that the improvement was "not exceptionally significant", and predicted that Elan would be asked by the US Food and Drug Administration (FDA) to embark on new trials before Antegren could be approved as a Crohn's treatment.

The fact that comparable Crohn's drugs are already on the market means the agency is not "under pressure" to approve Antegren, according to Mr Frawley.

A spokeswoman for Elan said yesterday that clinical trials for Antegren were ongoing.

She said further details on progress would emerge over the short term.

The company is likely to deliver an update on product development at its annual general meeting in Dublin next week.

Shares in Elan gained 10 cents yesterday to close at €4.90.