A divided panel of the U.S. Court of Appeals for the Second Circuit has vacated the conviction of Alfred Caronia, a former pharmaceutical sales representative who marketed a narcolepsy drug for so-called off-label uses not approved by the Food and Drug Administration. In an opinion released Monday in United States v. Caronia, the panel voted 2-1 to reverse the defendant’s 2009 conviction on the ground that it violated his First Amendment right to free speech.

In interpreting the Food, Drug and Cosmetic Act (FDCA), the panel found that the law’s provisions prohibiting the misbranding of prescription drugs do not make off-label promotions illegal, as long as such marketing is truthful and not misleading. The decision calls into question the government’s ability to prosecute misbranding charges based on off-label promotions. It also potentially affects the government’s ability to rely on a drug manufacturer’s distribution of truthful, non-misleading information about a drug’s off-label uses in such a prosecution.

In Caronia, the defendant was convicted of conspiracy to introduce a misbranded drug into interstate commerce for marketing the drug Xyrem for unapproved uses, such as treating chronic pain and fatigue. Under the FDCA, a drug’s labeling must contain “adequate directions for use.” FDA regulations define this term as “directions under which the lay [person] can use a drug safely and for the purposes for which it is intended.”

On appeal, Caronia argued that he was convicted for his speech, promoting the off-label use of an approved prescription drug, in violation of the First Amendment. After applying a First Amendment legal analysis, the Second Circuit agreed with the defendant. The panel ruled that the First Amendment does not permit the conviction of a pharmaceutical manufacturer or its sales representative solely on the basis of truthfully promoting off-label uses.

The court made clear, however, that false or misleading off-label promotion does not receive First Amendment protection. Additionally, the court did not address whether promotion of off-label uses could be relied on as evidence of the crime of introducing a misbranded drug into the stream of commerce.

As noted in the decision, the U.S. has “repeatedly prosecuted” drug companies and sales representatives for off-label promotion. While the Caronia decision arose from a criminal prosecution, it will have widespread implications for other enforcement activities where the government seeks to enforce the FDCA based on alleged off-label promotion, including in the context of False Claims Act cases.