Elan Study on Skelaxin Doesn't Infringe Classen Patent

On September 27, 2016, a Maryland district court ruled in favor of Finnegan client Elan Pharmaceuticals, stating that the company's study on muscle relaxant Skelaxin does not infringe a Classen Immunotherapies Inc. patent.

In 2001, the FDA approved Elan's abbreviated new drug application (ANDA) for Skelaxin, but later sought Elan's feedback on a proposal to change Skelaxin's label. Elan then conducted a clinical trial to analyze the effect of food on the absorption of metaxalone and submitted the results to the FDA to revise the label and to propose changes to the approval requirements for generic versions of the drug. Classen alleged that the study, the information that would be on Skelaxin's label, and Elan's activities related to filing for new patents as a result of what it learned infringed its patent. 

In 2012, the district court granted summary judgment in favor of Elan under the "safe harbor" of the Hatch-Waxman Act, which exempts generic drug makers from liability for infringing activity that's "reasonably related to the development and submission of information" to the FDA. The Federal Circuit applies this to brand name makers as well. Thus, the Federal Circuit affirmed this decision, but remanded the case only because the original district court opinion didn't say enough about whether some of Elan's activities met the "reasonably related" characterization. On remand, the court agreed with the Federal Circuit.