Drug: Avonex
Generic: Interferon beta1a
The company: Biogen Idec ($BIIB)
Patent expiration date: Dec. 31, 2013
Estimated Global Sales 2012: $2.9 billion

The scoop: Like a lot of biologic patents, Biogen's position on the big MS drug is a bit tricky to analyze. Evaluate Pharma put it on the 2013 list, despite the fact that Biogen Idec noted back in 2009 that it had extended the key Avonex patent 13 years beyond the original 2013 deadline. "For as much as we can tell, it looks like the patent is basically detailing the structure of the compound," says an Evaluate spokesperson. Also, that 2026 patent extension is being challenged, she adds, and it's likely that 2013 will prove to be a tipping point for the drug, with sales beginning to decline as new drugs elbow into the market. Biogen Idec, though, believes its patent position is secure. "This patent, which expires in September 2026, covers, among other things, the treatment of MS with our product Avonex," notes a company spokesperson. Regardless of perspective on the patent, though, Biogen should have time to manage a more orderly transition to BG-12, its new MS drug that is widely expected to snare FDA approval in the not-too-distant future. MS patients have traditionally had few therapies to pick from, but that's changing fast. Sanofi's ($SNY) Genzyme has won approval recently for Aubagio, and Lemtrada may get the green light as well.

For more:
Novartis, Sanofi unveil data backing their rival MS pills
Biogen Idec secures FDA nod for Avonex delivery accessory

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