FDA orders halt in enrollment in clinical trial for diabetes drug Avandia

It said the information "can be used’’ to update consent forms for new patients and current participants. Critics, including members of Congress, have said the current consent forms in use in the trial are inadequate given the extent of the scientific warning signs.

The potential dangers of Avandia have already discouraged enrollment in the trial.

The trial’s design called for global enrollment of 16,000 patients, with about a third in the United States. But the trial’s lead investigator, Hertzel Gerstein, of McMaster University in Ontario, Canada, said last week only about 1,120 patients had been recruited worldwide, because of the widespread safety concerns.

GlaxoSmithKline recently announced that India had suspended all participation in the TIDE trial in that country.

By a vote of 20 to 12, an FDA advisory panel last week recommended that the drug be permitted to remain on the market. But half of the members who voted to keep it on the market also supported strong restrictions on prescribing, including education programs about the risks for doctors and patients, which specialists predict will dramatically cut into GSK sales figures.

In a separate vote on whether the TIDE trial should continue, 19 panelists said yes, and 11 said no.

GlaxoSmithKline said today in a statement that new enrollment in the trial would be stopped "pending FDA review of recommendations from its Advisory Committee meeting July 13-14. Patients already enrolled may continue in the trial.’’

“This pause in enrollment will give clinical trial investigators and patients time to learn about the data presented to the FDA Advisory Committee and the Committee’s recommendations,” said Dr. Ellen Strahlman, GSK’s Chief Medical Officer. “We are committed to working with the FDA in the best interest of diabetic patients.’’

Avandia, which was approved for the market in 1999, was prescribed 2 million times by US doctors in 2009. It was once the largest-selling drug in its class, with more than $3 billion in global sales. It sold around $1 billion in 2009, with half of that revenue in the US.