Change to Troglitazone Label

OB/GYN News, Dec 15, 1999 by Mike Bykowski

For the fourth time since its approval, troglitazone's labeling has been changed to reflect the potential for serious and sometimes fatal liver toxicity.

Troglitazone, the "insulin-sensitizer" marketed as Rezulin by Parke-Davis, is no longer indicated as monotherapy for type 2 diabetic patients, according to the Food and Drug Administration.

The recommended frequency of liver function monitoring has also been increased: In addition to checking liver function before treatment, liver function tests should now be performed every month for the first year of treatment and quarterly thereafter.

There have been 43 reported cases of acute liver failure among the 1.2 million patients treated with troglitazone since it entered the U.S. market in March 1997.

A press release issued by Warner-Lambert, which owns Parke-Davis, said that physicians can continue to use the drug "as monotherapy in current patients who are well controlled, compliant with liver enzyme monitoring requirements, and who have tolerated the drug without any evidence of adverse liver events."

The revised labeling includes a newly approved indication for troglitazone: as a component of triple therapy in combination with a sulfonylurea and metformin in type 2 diabetics who are not adequately controlled with a sulfonylurea and metformin (Glucophage).