The Supreme Court handed down its decision this morning in the Wyeth v. Levine federal preemption case, holding, by a 6-3 majority, that "Federal law does not pre-empt [plaintiff Diana] Levine’s claim that [the Wyeth drug] Phenergan’s label did not contain an adequate warning about the IV-push method of administration." Justice Stevens wrote the majority opinion, joined by Justices Kennedy, Souter, Ginsburg, and Breyr, and with Justice Thomas concurring in the judgment. Justice Alito wrote a compelling dissenting opinion, joined by Chief Justice Roberts and Justice Scalia. Guest blogger Bert Rein and I separately commented on the case here, here, here, and here. According to Justice Stevens' majority opinion, "The history of the [Food Drug and Cosmetics Act] shows that Congress did not intend to pre-empt state-law failure-to-warn actions." Fair enough, but this isn't a typical failure-to-warn case. As Justice Alito's dissent notes, Ms. Levine alleged not only that the warning on Phenergan's label wasn't strong enough, but that Phenergan was "not reasonably safe for intravenous administration," and that Phenergan's label should have indicated that the drug "should not be used intravenously." But, that's a question regarding FDA's approval of the product for that use, not merely the sufficiency of the warning. Consequently, the decision reaches to the very core of FDA's statutory competence. FDA made a regulatory decision that the benefits of IV injection outweighed the risks, and the agency permitted the product to be labeled accordingly. Furthermore, there are no allegations that Wyeth hid any information about the risks of IV injection, nor that any new information regarding the risks of IV injection have arisen that would call that decision into question since FDA made it. So, letting a Vermont jury penalize Wyeth for not ruling out IV injection on Phenergan's label is tantamount to letting a group of laymen over-rule FDA's expert opinion regarding safety. It would have been one thing if new evidence of risk had arisen since FDA approved the label, or if Wyeth were accused of hiding information from the FDA or mis-representing the data it did provide. In such a case, exposing a drug manufacturer to tort liability would not be over-riding FDA's expert judgment. But that is decidedly not the case here. Indeed, the negligent act that actually caused Ms. Levine's unfortunate injury was not an IV push injection into a vein, but the physician's assistant's botched administration. The physician's assistant injected Phenergan into Ms. Levine's artery, in direct contravention of six label warnings against arterial injection. More or sterner warnings against arterial injection would not have prevented Ms. Levine's injury. Thus, the Supreme Court could have and should have held in Wyeth's favor with a narrowly tailored opinion confined to the facts of this case. Doing so would not have insulated wrong-doers from punishment, but would have recognized that Congress gave FDA statutory authority over questions of safety and efficacy because it believed that only a federal expert body could effectively balance the benefits and risks of new medicines. So, not only is the majority's decision bad policy, it's also bad law.