Bristol-Myers Squibb Co. has been sued by two insurers that accuse it of overcharging for BuSpar, an anti-anxiety drug.
Mutual of Omaha Insurance Co. and Guardian Life Insurance Co. of America, which manage prescription-drug plans for companies, allege that the world's fifth-largest pharmaceutical company abused the patent process to block competition for BuSpar from 1995 to 2001.
Bristol-Myers agreed in January to pay $670 million to settle antitrust suits over BuSpar and Taxol, its cancer drug. The company also agreed last week to stop misusing patent laws to block cheaper generic drugs from coming to market.
A spokesman for Bristol-Myers did not return a call seeking comment.
Shares of the company gained 21 cents to $21.65 on the NYSE.