2 FDA rebels criticize inclusion of Avandia defenders on July advisory panel

Two FDA officials who have been highly vocal critics of Avandia (rosiglitazone) are now suggesting that the FDA stacked the deck in favor of rosiglitazone at the July advisory committee meeting by including panel members from the earlier 2007 meeting that recommended against removing the drug from the market.

In a letter published in BMJ, David J Graham and Kate Gelperin note that at the extraordinary meeting this July the FDA invited not only the current members of two advisory committees but also all members from the 2007 meeting, “even though they were no longer active members of either committee.” They observe that half of the 32 committee members had also attended the 2007 meeting, and all but one had voted to keep the drug on the market. They write:

The addition of these former members substantially biased the results of the vote on whether rosiglitazone should be withdrawn from the market (table⇓). Members voting for the first time were 4.4-times (95% confidence interval 1.1 to 17.0; P=0.01) more likely to vote that rosiglitazone be withdrawn from the market than were members who had voted previously to keep it on the market.

By inviting these former members to participate in the 2010 meeting, CDER biased the outcome of the vote in favour of rosiglitazone remaining on the market. Had these former members not been included, the vote would have been 10 out of 17 (59%) in favour of rosiglitazone withdrawal, with an additional three in favour of severely restricted distribution.