Biogen Idec has completed its purchase of Elan Corporation’s interest in TYSABRI ® (natalizumab) and has gained full strategic, commercial and decision-making rights to TYSABRI. The transaction was originally announced on February 6, 2013.

“Full ownership of TYSABRI is an important step for Biogen Idec that further solidifies our leadership in MS,” said George A. Scangos, Ph.D., chief executive officer of Biogen Idec. “The powerful efficacy of TYSABRI makes it an important treatment for many people living with MS and we believe it has a solid growth trajectory for years to come. We are grateful to Elan for more than a decade of collaboration on TYSABRI, and for their work to provide a seamless transition as we finalized the transaction.”

Further details and updated financial guidance will be provided during Biogen Idec’s upcoming first quarter 2013 earnings announcement.