The Irish pharmaceutical company Elan Corp Plc and its US partner Biogen Idec Inc released information on Monday that their MS drug Tysabri has been found to bring improvements in the condition of patients after two years. It had previously been though only to slow the progress of the disease. In the wake of this new information shares in Elan rose by almost five percent as commentators posit that the company's analysis of these results might increase confidence among doctors.