## Facts

- Merck Sharp & Dohme Corp. manufactured Fosamax, a prescription drug used to treat and prevent osteoporosis.
- In 1998, the Food and Drug Administration (FDA) approved Fosamax labeling without a warning about unusual thigh-bone stress fractures (atypical femoral fractures), even though Merck scientists knew the drug could theoretically cause such fractures.
- Between 1999 and 2010, more than 500 women who took Fosamax suffered stress fractures and brought state-law failure-to-warn suits, alleging Merck should have warned earlier about the risk.
- In 2008, Merck asked the FDA for approval to add a warning about stress fractures to Fosamax’s label, but the FDA rejected the proposed label change.
- At the time of the 2008 submission and rejection, neither Merck nor the FDA was certain that the developing evidence showed a strong enough connection to require a new warning.
- The FDA did not require Merck to add an atypical-fracture warning until 2010.
- In the Fosamax multidistrict litigation, Merck argued that federal law preempted the state-law failure-to-warn claims because the FDA would not approve the warning that plaintiffs alleged state law required.
- The district court granted summary judgment for Merck on impossibility preemption.
- The Third Circuit reversed and remanded, reasoning that a jury should decide whether it was “highly unlikely” the FDA would have approved an adequately worded warning.

## Issues

1. Whether the Wyeth “clear evidence” inquiry for impossibility preemption—whether the FDA would have rejected a labeling change required by state law—is a question for a judge or a jury.
2. What “clear evidence” means in this setting, including what the manufacturer must show about what it told the FDA and how the FDA responded.

## Decision

- The Supreme Court vacated the Third Circuit’s judgment and remanded.
- The Court held that the “clear evidence” preemption question is primarily one of law for a judge to decide, not a jury.
- The Court explained that “clear evidence” is evidence showing that (1) the manufacturer fully informed the FDA of the justifications for the warning required by state law, and (2) the FDA informed the manufacturer that it would not approve a label change adding that warning.
- The Court did not decide whether Merck ultimately met that standard on this record; it directed the lower court to apply the clarified framework.

## Legal Principles

- State-law failure-to-warn claims involving brand-name prescription drugs can be preempted when federal law makes it impossible for the manufacturer to satisfy both federal labeling requirements and the warning duty imposed by state law.
- The Wyeth “clear evidence” inquiry asks whether the FDA, acting with full information, would have rejected the warning that state law allegedly required.
- The existence and legal effect of FDA action bearing on disapproval is primarily a question of law for the court, based on the agency’s communications and the governing statutory and regulatory scheme.
- A jury may resolve genuinely disputed historical facts that matter to the court’s preemption analysis, but the ultimate preemption determination belongs to the judge.
- “Clear evidence” in this context is not a special jury burden of proof; it describes the kind of showing the manufacturer must make: full disclosure to the FDA and an FDA communication that the agency would not approve the warning at issue.

## Conclusion

Merck Sharp & Dohme Corp. v. Albrecht holds that impossibility preemption for FDA-regulated drug labeling—whether there is “clear evidence” the FDA would have rejected the warning that state law allegedly required—is principally for a judge to decide, and it requires a showing that the manufacturer fully informed the FDA of the justification for the warning and that the FDA communicated it would not approve adding that warning; the Court vacated and remanded for the lower courts to apply that standard to Merck’s Fosamax record.


Merck Sharp & Dohme Corp. v. Albrecht, 139 S. Ct. 1668 (2019)