We’ve written about the dangers of the diabetes drug Avandia and have told Congress about an unethical international clinical trial, requested by the FDA, being performed by Avandia’s manufacturer, GlaxoSmithKline.

Now Public Citizen and Canadian researcher/physician David Juurlink go straight to the source, sending a letter to FDA Commissioner Margaret Hamburg asking her to halt the study, which pits Avandia against its competitor, Actos.

From the Reuters story:

“A wealth of data now suggests” that Avandia carries greater risks than Actos, the researchers said. Patients are also not adequately informed about the safety differences between the two medicines when deciding whether to participate in the trial, they added.

But FDA officials, who have said they are already taking a closer look at Avandia, are not likely to act so quickly.

And the Los Angeles Times:

In act, both drugs [Avandia and Actos] have been tagged with safety issues: In addition to raising rates of cardiovascular events, the class of Type 2 diabetes drugs known as thiazolidinediones (or TZDs) have been linked in studies to higher rates of edema, macular edema, bony fractures, anemia and acute liver injury. Older diabetes medicine such as metformin and sulfonylurea are widely believed to be safer alternatives.

But to no avail — the FDA likely won’t examine the study until July, FiercePharma reports.