-
OxyContin patent expires, fears of abuse return
The November 2011 expiration of Pfizer's patent on the cholesterol drug Lipitor and Ranbaxy Labs' release of the generic version received significant play in the media, particularly due to the theretofore status of Lipitor (atorvastatin calcium) as the drug with the highest sales in the country, $7.7 billion in the United States, according to healthcare analytics firm IMS Health.