In Thompson v. Allergan USA, Inc., --- F. Supp. 2d ---, 2014 WL 308794 (E.D. Mo. Jan. 28, 2014), the United States District Court for the Eastern District of Missouri held that federal law preempted claims against a drug manufacturer for allegedly “overfilling” vials of eye drop prescription medication.

In Thompson, plaintiff brought a putative class action for violations of the Missouri Merchandising Practices Act (MMPA) and for unjust enrichment against the manufacturers of eye drops alleging that that defendants “excessively overfill[ed]” single-use eye drop vials with more liquid than the recommended dosage. Id. at *1. Plaintiff claimed that by overfilling the vials, defendants made the eye drops more expensive and forced consumers to purchase more eye drops than a consumer could use under the dosage instructions. Id.

Applying the reasoning in PLIVA, Inc. v. Mensing, 131 S. Ct. 2567 (2011), and Mutual Pharmaceutical Co., Inc. v. Bartlett, 133 S. Ct. 2466 (2013), the court found plaintiff’s state law claims were preempted under federal law because defendants were unable to independently lower the volume of eye drops in each vial under an FDA regulation forbidding “qualitative or quantitative formulation of the drug product, including active ingredients, or in the specifications provided in the approved application.” Thompson, 2014 WL 308794, at *5-6 (citing 21 C.F.R. § 314.70(b)(2)(i)). Because reducing the amount of medicine in each vial of eye drops would constitute a major change requiring FDA approval, the court concluded that it was impossible for defendants to independently comply with the state law duties alleged in plaintiff’s complaint. Id. at *6.

Thompson demonstrates that federal preemption may turn on individualized facts, and litigants should be vigilant for preemption arguments that fit the unusual facts of the claim or product at issue. And while the claim in this case was atypical, the decision may be useful more broadly in combating design or manufacturing defect claims aimed at the manner in which products are formulated or packaged.