AbbVie and Biogen inch toward the FDA with once-a-month MS drug

Partners Biogen Idec ($BIIB) and AbbVie ($ABBV) are touting late-stage results for their new, monthly multiple sclerosis treatment, preparing to hand in regulatory applications next year and contend in a crowded market.

The drug, daclizumab, is a subcutaneous treatment designed to correct the immune system and improve symptoms of relapsing-remitting multiple sclerosis, the most common form of the disease.

In a Phase III trial on about 1,800 subjects, the treatment met its primary endpoint of reducing patients' relapse rate, beating Biogen's blockbuster weekly treatment Avonex by 45%. Daclizumab, to be marketed as Zinbryta, also met its secondary endpoints of better reducing lesions, cutting the risk of worsening MS and leaving patients relapse-free at 96 weeks. The new drug failed to significantly improve three-month disease progression, however.

On the safety side, daclizumab charted a higher rate of serious infections than Avonex, plus elevations in liver toxicities and an increased number of injection-related problems.

Now the partners are gearing up to file applications for FDA and European approvals in the first half of next year, hoping daclizumab's improvements over Avonex--which rang in $3 billion in sales last year--will help it carve out a share of the MS market.

But that space is packed with players and further crowding, thanks largely to daclizumab stakeholder Biogen. Tecfidera, the company's new oral treatment, debuted in April 2013 and has minted more than $2 billion in sales ever since, shifting a landscape long dominated by Teva ($TEVA) and its soon-to-come-off-patent Copaxone.

And while daclizumab's monthly schedule and self-administered dosing system could score points among physicians and patients, Biogen is already at work promoting an every-two-weeks MS treatment in Plegridy, approved last month. Analysts say that drug could bring in $1 billion a year at its peak, but it'll likely cannibalize Avonex sales on the way there. Same goes for daclizumab, which some expect to top out at $500 million.

For AbbVie, however, elbowing into the MS market is less of a zero-sum game. The company bought into daclizumab through its $700 million deal for Facet Biotech back in 2010, and the drug has long been one of its top late-stage prospects.

- read the results

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