In the latest setback for American Home Products Corp., the FBI is examining how the company won approval to sell the diet drug Redux.
AHP had pulled Redux and another weight-loss drug, Pondimin, from the market in 1997 over safety concerns and faces thousands of lawsuits.
A federal law enforcement official, who requested anonymity, confirmed Thursday that a preliminary investigation was underway but gave no other details.
The company, based in Madison, N.J., said it was not aware of any probe, and the FBI said it could not confirm or deny an investigation was ongoing. The Food and Drug Administration had no comment.
The FBI conducts preliminary probes to determine whether to launch a formal investigation of possible criminal wrongdoing.
The news sent AHP shares falling $2.25 to close at $40.06 on the New York Stock Exchange.
The company faces more than 4,000 civil lawsuits over Redux and Pondimin, one-half of the diet drug cocktail fen-phen. Last month, a Texas jury awarded one fen-phen user $23.3 million.
In addition to the diet drug trouble, the company withdrew a painkiller in 1998, suspended distribution in July of a vaccine to prevent childhood diarrhea and last month settled suits with 36,000 women who used its Norplant contraceptive. Also last month, AHP recalled 600,000 emergency allergy kits. The drugs used in the kits weren't potent enough, the company said.
The FDA approved Redux in 1996, but AHP withdrew it and Pondimin from the market in 1997 after both were linked to heart valve damage.
The Wall Street Journal reported that the FBI was trying to find out whether AHP told the FDA everything it knew about adverse reactions to the diet pills before the agency approved sales in the U.S.
On Thursday, AHP said it was unaware of any investigation of how it handled Redux--known generically as dexfenfluramine--or Pondimin.
"American Home Products is absolutely unaware of any investigation by the U.S. Department of Justice or the Federal Bureau of Investigation relating to diet drugs," said AHP's general counsel, Louis Hoynes.
"We know of no basis for such an investigation, and we are confident that American Home Products' actions with respect to Pondimin and Redux were at all times lawful and appropriate," he added.
Both Redux and Pondimin are marketed by the company's Wyeth-Ayerst division. Interneuron Pharmaceuticals Inc. of Lexington, Mass., licensed the rights to Redux to Wyeth-Ayerst in 1992. A spokesman for Interneuron, which led the drug through the FDA approval process, said it had not been contacted by the FBI.
FDA advisors who reviewed Redux before it was approved initially recommended that the agency reject it. But the panel later reversed itself and voted 6 to 5 to recommend approval in November 1995. The FDA usually follows its panels' advice.
Separately, lawyers for a New York girl filed a $500-million suit against AHP late Wednesday, alleging the company's vaccine for diphtheria, tetanus and pertussis caused the girl permanent and severe brain damage when administered in 1993.