Biogen/Elan's Tysabri back on US market, with limits

US firm Biogen Idec and Ireland's Elan Corp have announced the commercial availability of Tysabri (natalizumab) for the treatment of relapsing forms of multiple sclerosis in the USA. As previously announced, the Food and Drug Administration approved the supplemental Biologics License Application for the reintroduction of Tysabri, marketing of which was suspended last year on safety concerns (Marketletters passim), as a monotherapy treatment for relapsing forms of MS to slow the progression of disability and reduce the frequency of clinical relapses.

The FDA granted approval for reintroduction based on the review of Tysabri clinical trial data; revised labeling with enhanced safety warnings; and a risk management plan (TOUCH Prescribing Program) designed to inform physicians and patients of the benefits and risks of treatment and minimize potential risk of progressive multifocal leukoencephalopathy. Under the TOUCH Prescribing Program, only prescribers, infusion centers and pharmacies associated with infusion centers registered in the program are able to prescribe, infuse or distribute the drug.