Chris Hill: Obviously, here in America there is a huge and growing challenge with obesity. How do obesity drugs play into all of this?

David Williamson: Obesity drugs -- we actually had the first one approved in over a decade this year, by VIVUS. It's called Qsymia. It has a competitor in Arena Pharmaceuticals, whose drug Belviq was also approved. Qsymia is on the market. Belviq is not yet, so really it's going to be also a 2013 story, how these two drugs go after each other.

It's exciting news, in the fact that it's a landmark change. It's a pharmaceutical class that's had all sorts of issues. We've seen Meridia, Fen-Phen; these drugs have been pulled from the market. There have been health issues. There are serious safety issues with both of these drugs as well, so it remains to be seen.

The stocks have been huge success stories. They've been multibaggers in 2012, and I think that's why a lot of investors are excited, but now comes the hard part, which is selling the drugs. We'll see how these go, but as far as investors were concerned, this big run-up, and these were some of the top performing stocks in the whole sector, so a lot of attention on these first obesity drugs approved in a long time.

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