The Type 2 diabetes drug rosiglitazone (brand name Avandia) has had a rough history — beginning with a study three years ago that found a 43% higher risk of heart attack associated with the drug, and recently as the focus of a report by the US Senate Finance Committee that accused GlaxoSmithKline, Avandia’s manufacturer, of intimidating physicians and playing down the cardiovascular risk posed by the drug. Glaxo has long maintained that Avandia is safe and remains an important option for doctors and patients. But if a consumer advocacy group has its way, Glaxo will not get another chance to prove Avandia’s safety.
Glaxo is currently beginning a massive study of Avandia, comparing it with competitor drug pioglitazone (Actos), called TIDE (Thiazolidinedione Intervention With Vitamin D Evaluation). According to an article from Reuters, the trial aims to study 16,000 people before the year 2015, using 137 locations in 14 countries. The trial was requested three years ago by the US Food and Drug Administration in response to the first allegations of a higher cardiovascular risk associated with Avandia. Since then, however, more evidence of Avandia’s heart risk has emerged, prompting the nonprofit group Public Citizen to call for an end to the TIDE trial, calling it “unethical” and “dangerous,” according to a post on the Los Angeles Times blog Booster Shots. In a letter to FDA Commissioner Margaret Hamburg, Public Citizen argues that TIDE will most likely not produce more reliable evidence than already exists, yet exposes thousands of people already at high risk for heart problems to a drug known to increase that risk.
This renewed controversy comes at the same time as reports that Glaxo has settled hundreds of claims alleging that Avandia caused heart attacks or other cardiovascular problems. The total settlement is said to be around $60 million, considered to be a small amount. However, an upcoming court case involving thousands of claims could result in a much greater settlement.
In a published statement, Glaxo stressed that the board overseeing TIDE “has not expressed any concerns regarding the safety of participants in the study and has recommended that the study continue without modification.” And a spokesperson for the company noted that Avandia has been shown to control blood glucose levels for up to five years.
The FDA is currently reviewing the data on Avandia, and an advisory panel is planning to meet in July to discuss the drug’s safety. It seems unlikely, however, that the FDA will stop TIDE; the agency has specifically called for more data to evaluate Avandia, which the trial aims to provide.
What do you think — is it ethical to randomly assign a drug with safety concerns to trial participants? Would you participate in the TIDE trial? Is the FDA right to want definitive evidence of Avandia’s risks, compared with Actos? How much risk should be considered acceptable in a Type 2 diabetes drug, given the alternatives available? Leave a comment below!