FDA, EMA accept applications to expand Tysabri's label

Biogen Idec Inc. (NASDAQ:BIIB) and partner Elan Corp. plc (NYSE:ELN) said FDA and EMA accepted for review regulatory applications to expand the label of multiple sclerosis (MS) drug Tysabri natalizumab. The partners are seeking approval for Tysabri as first-line treatment for relapsing forms of MS in anti-JC virus (JCV) antibody negative patients. Elan said the PDUFA date for the sBLA to expand Tysabri's label is next half, but the exact date is not disclosed.

Tysabri is approved in the U.S. to treat relapsing-remitting MS (RRMS), and in the EU to treat highly active RRMS in adult patients who have failed to respond to beta interferon or who have rapidly evolving, severe RRMS. The partners said that because of an increased risk of developing progressive multifocal leukoencephalopathy (PML), currently Tysabri is generally used in patients who are not responding to or who are unable to tolerate an alternative therapy. Last year, both the U.S. and EU labels were updated to note that anti-JCV antibody positive status is a risk factor for PML. The partners said a first-line label "will allow all appropriate anti-JCV antibody negative patients to consider Tysabri early in the course of treatment, regardless of the level of disease activity or prior treatment history." ...