>XNPT's drug
I'm assuming an IND mid-2012. The Phase I will tell us quickly whether or not they have a drug.
In terms of regulatory strategy, I'm less clear. The two possible routes are 505(b)(2) and (much less likely) a full NDA. For 505(b)(2), the issue is they will not have right of reference to Biogen's data, so they would have to rely on published data and the FDA approval, and they would perhaps get sued by Biogen. A clinical trial would still be needed as the PK would be different - so basically it would be the same strategy they are using with baclofen, with a single pivotal Phase III trial.
In terms of the likely suite or citizen's petition by Biogen, the issue would be just what data they could use. Here Biogen just has a use patent, so ultimately they can't block XNPT's drug, they can just try to make it harder to get approval. (There was a somewhat analogous skirmish between Pfizer and Dr Reddy over amlodipine - there the issue was a patent extension and a different salt of the drug. In that case the FDA approved the competitor drug under 505(b)(2) but it was ultimately blocked on COM patent grounds).
Peter
Market Data 
Markets 
AI
