European regulators have approved Biogen's application to market a subcutaneous (SC) injection of Tysabri (natalizumab) to treat relapsing-remitting multiple sclerosis (MS).

The new formulation offers comparable efficacy and safety to intravenous (IV) Tysabri, and makes the drug the only high-efficacy MS therapy to offer two routes of administration.

The SC and IV formulations of Tysabri are dosed 300mg, every four weeks by a healthcare provider, but the SC option expands the clinical settings for treatment beyond infusion centres, and offers a shortened time-frame for administration.

“The subcutaneous administration of Tysabri expands choices when it comes to controlling MS disease activity,” said Sven G. Meuth, professor of Neurology and director of the Clinic of Neurology at the University Hospital of Düsseldorf.

“I believe the SC administration offers an opportunity to receive comparable efficacy and safety to the intravenous formulation with reduced administration time which may be meaningful for patients. For physicians, the SC administration offers the ability to prescribe and administer Tysabri in their practice, providing more locations where patients can be treated.”

Approved by the EC in 2006, Tysabri's efficacy and safety have been shown through clinical trials and extensive real-world evidence gathered over nearly 15 years, Biogen noted.