The world's largest drug manufacturer must answer off-label promotion charges brought by a new adversary. Not FDA, with its warning letters and threats of marketing sanctions, and not the Office of the Inspector General (OIG) at Health and Human Services, which often sues for fraud, forces huge settlements, and requires companies to do business under restrictive corporate integrity agreements. Instead, the company faces a class-action civil suit from insurance companies and union welfare funds, groups that, until recently, Pfizer regarded primarily as customers-or at least people who picked up the tab for customers. Now, led by the Welfare Fund of a Teamsters local from New Jersey, third-party payers are suing under RICO, the Racketeering Influenced and Corrupt Organizations Act. If their suit is successful, payers who have covered billions of dollars worth of Lipitor (atorvastatin) over the past five years will receive treble damages for the cost of off-label prescriptions. The suit may also attract..