Ireland’s Elan Corporation received a boost this morning after revealing that a two-year clinical trial of its new multiple sclerosis offering, Tysabri (natalizumab), which is partnered with Biogen Idec, achieved its endpoint of slowing the progression of disability amongst MS sufferers. Elan’s share price climbed by as much as 5% in Ireland and 8% in London during morning trading today on the results, which further underpin expectations for drug that is expected to become the market-leading treatment for all forms of relapsing remitting MS [[08/02/05a]].

Data from the 942-patient, Phase III trial, known as Affirm, showed a 42% reduction in the risk of disability progression in patients with relapsing forms of MS. Importantly, the results also showed a sustained 67% reduction in the rate of clinical relapses over two years, confirming previous one-year data.

Lars Ekman, executive vice president and president of research and development at Elan, heralded the results a “major milestone in the treatment on MS”. He said: “These two-year data strengthen our belief that Tysabri will become the leading therapy for MS patients.”

Tysabri – formerly known as Antegren – is the first humanised monoclonal antibody approved for the treatment of MS. It won the green light from the US Food and Drug Administration in November last year, based on one-year data from the Affirm trial [[24/11/04a]], and is currently under review with the European regulatory authorities [[04/06/04c]]. Elan and Biogen Idec are also awaiting the European nod for Tysabri in the treatment of Crohn’s disease [[29/09/04a]], and are also researching the product as a potential treatment for rheumatoid arthritis, with a Phase II trial currently underway.