A somewhat skeptical Matthew Herper at Forbes did a Q&A with Glaxo's Patrick Vallance on the big news that it's buying Sirtris at $22.50 a share. Sirtris has been gaining headlines for its work in the anti-aging field, but the stock price has lagged significantly. Vallance sees great science, great scientists and lots of potential. One excerpt: "We're forever investing in high-risk things. That's what we do in the pharmaceutical industry. We're pretty clear that we see a big opportunity here." On big vs. small: "Now they can do things with a scale and know-how that's much more difficult if you're in a group of 60 people than if you're in a large organization that has done this for years." Report