Lawyers blaming heart abnormalities on the painkillers Darvon and Darvocet and their generic equivalents are trying to jumpstart their cases on appeal after a federal judge dismissed the vast majority of the actions.

In a petition filed before the U.S. Court of Appeals for the Sixth Circuit, plaintiffs’ attorney Louis Bograd wrote that the cases raised an issue of first impression: Can patients bring their state law claims against a generic manufacturer that, by continuing to sell an “unreasonably dangerous prescription drug,” violated the federal misbranding statute?