The past year has been a challenging one for Pfizer, the world's largest pharmaceutical company. Its stock price has fallen as it has struggled to boost research productivity, going so far as to cut research jobs along with sales positions and spending $68 billion to purchase Wyeth in a bid to strengthen its product portfolio. Its troubles are not recent, and when it announced last September that it was getting out of the business of developing new drugs to prevent or treat cardiovascular disease, the news did not come as a complete surprise.