The Misery Of Pfizer Could Be The Joy Of Texas: Generic Drugs Are On The Rise By: Pat Carpenter | - Pfizer can't be happy. Its patent on the best-selling drug in the world, Lipitor, expires in 2011, which doesn't give the pharmaceutical giant much time to figure out how to compensate for the billions of dollars in sales that will be lost when it happens, courtesy of generic companies reproducing the medicine's active ingredients. The United States alone buys $5 billion worth of the brand-name drug every year.