Why Does the FDA Overrule Its Expert Committees’ Recommendations?

The Food and Drug Administration (FDA) creates committees of experts who recommend whether new drugs should be approved or rejected. The popular press and earlier studies commonly report that the FDA almost never overrules these recommendations. Some argue that the experts and FDA are like-minded because both have financial ties to drug companies. Others claim that both are risk averse and avoid approving effective but risky drugs. We show that FDA overrules are more common than some believe (16 percent of cases) and that experts’ risk aversion better explains overrules than their financial ties to drug companies. The recent controversial overrule for Alzheimer’s drug Aduhelm illustrates how the FDA is willing to take the risk of approving a drug that the experts almost unanimously reject. This is consistent with our finding that committees with top experts reject more drugs, perhaps to protect their reputations