FDA Halts Avandia Study EnrollmentJul 21, 2010 | Parker Waichman LLP
US health regulators have ordered GlaxoSmithKline to stop recruiting patients for an Avandia trail. The trial, called TIDE (Thiazolidinedione Intervention With Vitamin D Evaluation), was designed to compare the long-term effects of Avandia with another diabetes drug called Actos.
The decision by the Food & Drug Administration (FDA) comes a week after one of its advisory panels voted 20-12 to recommend that Avandia be allowed to stay on the market. However, 10 panel members voted that its sales should be restricted and that warnings on its label regarding heart risks be strengthened. Nineteen panelists said TIDE should continue, and 11 opposed it.
Since November 2007, Avandia’s label has included a black box warning – the FDA’s strongest safety alert – detailing its association with myocardial ischemia. The black box was added after the Cleveland Clinic published a meta- analysis of 42 clinical trails that showed patients taking Avandia had a 43-percent higher risk of having a heart attack. Since the addition of the black box, evidence linking Avandia to an increased risk of heart attacks has continued to accumulate.
Actos has not raised as many safety concerns as Avandia. For some time now, scientists inside and outside the FDA have opposed TIDE, saying it is unethical to compare Avandia, with its known cardiac risks, with a seemingly safer alternative.
According to The Boston Globe, the FDA said it halted recruitment in TIDE because it needs time to study new evidence of the Avandia’s risks. The agency is demanding that Glaxo update physicians and ethics oversight boards involved in the trial regarding all new safety information about the drug. The agency did not say how long the enrollment halt would last.
The people already participating in the trial will be allowed to continue with it, the FDA said.
As we reported in May, TIDE was already having trouble recruiting new members. At that time, two research sites had dropped out of TIDE because of enrollment issues. An official with one of them – Wake Forest University Baptist Medical Center in North Carolina – told The Wall Street Journal that it was “not succeeding in recruiting anybody.”
In April, Glaxo opened up a dozen research sites overseas, some in developing countries including Pakistan, India, Mexico, Latvia and Colombia.
According to The Boston Globe, TIDE called for the enrollment of 16,000 patients, but so far, only 1,120 patients had been recruited worldwide. Recently, India had suspended all participation in the trial.