Avandia’s Farewell

It seems safe to say that it’s finally over: After over three years of clashes among scientists, pharmaceutical companies, and government regulators, the fate of Type 2 diabetes drug rosiglitazone (brand name Avandia) is sealed.

Two months after it ordered a halt to enrollment in a large-scale clinical trial of Avandia’s safety that it had requested three years earlier, the US Food and Drug Administration (FDA) issued a conclusive ruling on the heart risks associated with the drug. In a rare set of coordinated statements by the FDA and the European Medicines Agency (EMA), the FDA’s European Union counterpart, the two agencies announced that after reviewing all available data, they had come to the conclusion that the higher risk of heart attack associated with Avandia outweighed the drug’s benefits. But the two agencies set different policies in response to this conclusion. As described in a Reuters article, the EMA will simply remove Avandia from the market within the coming months. The FDA’s new policy, however, will require that doctors first exhaust all other options for new patients before they can prescribe Avandia. Current Avandia users can continue taking the drug only after reading a statement about its cardiovascular risks and acknowledging their understanding, and if their doctor certifies that Avandia is still the right choice for them. Given the wide variety of blood-glucose-lowering drugs available, this rule ensures that Avandia will all but disappear from the US market.

The new FDA policy underscores the reluctance of some doctors to switch patients from Avandia to other treatments in spite of the bad press and official safety warnings the drug has received in the last three years. Although Avandia sales revenue dropped from $3 billion in 2006 to $1.2 billion in 2009, according to the Reuters article, the later sales figure nevertheless represents a substantial sum for Avandia’s manufacturer, GlaxoSmithKline. FDA regulators may now simply be forcing the result they hoped their earlier warnings would achieve.

But why not simply ban sales of the drug, as the EMA will do? A possible explanation, of course, is that the FDA wants Avandia available when other available treatments fail to achieve their desired results. But given the expectation that Avandia will almost completely disappear — a prominent scientist quoted in the Reuters article estimates that sales will drop by 99% within six months — it appears that few, if any, patients will fall into such a situation. This raises the possibility of a more cynical motivation: Many experts believe that the drug’s removal from the market would embolden lawsuits on behalf of Avandia patients who suffered heart attacks. While such lawsuits can proceed without the drug’s removal, such an action by the FDA would undoubtedly be submitted as evidence that GlaxoSmithKline failed to adequately examine the drug’s risks in the first place. It is worth noting that the FDA has not always taken a more liberal approach to drug safety than European agencies. The drug metformin, now a mainstay of Type 2 diabetes treatment in the United States, was first approved by the agency in 1994 — 36 years after it was introduced in Europe.

What do you think — did the FDA and the EMA act appropriately in response to safety concerns, or should they have let the safety trial of Avandia reach its conclusion? Does the FDA’s policy of ending most use of Avandia without officially removing the drug make sense? If you currently take Avandia, how do you feel about the prospect of switching to a different treatment for your diabetes? Are you a former user who switched already? Leave a comment below!