Antidiabetic Drug Withdrawn from Market
The request followed the agency's review of recent safety data on the drug and two other glitazone antidiabetic agentsrosiglitazone and pioglitazone. All three drugs had FDA-approved labeling for the treatment of type 2 diabetes mellitus.
Reports of severe liver toxicity associated with troglitazone therapy led to a July 1998 warning from the company for health care professionals to more closely monitor patients' liver function. In June 1999, FDA and the company advised health care professionals not to use the drug as initial single-drug therapy for type 2 diabetes and to check patients' liver function before starting troglitazone therapy and periodically thereafter.
Despite these actions, pressure mounted for FDA to take a more aggressive course, and rumors ensued. On Feb. 24, Warner Lambert issued a statement denying that Rezulin had been pulled from the U.S. market. Responding March 10 to "repeated inaccurate reports regarding Rezulin," the company said it wanted to discuss with FDA the drug's safety and that of other glitazone agents. A week ago, the American Diabetes Association announced that, on the basis of the publicly available research data, the organization did not consider the safety concerns about Rezulin to extend to the other two glitazone antidiabetic agents.
In announcing the withdrawal of Rezulin from the U.S. market, FDA's Janet Woodcock, director of the Center for Drug Evaluation and Research, said that continued use of the drug "poses an unacceptable risk to patients." Similar diabetes drugs offer patients safer alternatives, she said.