Last week, the U.S. Court of Appeals for the Federal Circuit issued an opinion in Biogen International GmbH v. Mylan Pharmaceuticals Inc., No. 2020-1933 (Nov. 30, 2021), affirming the district court’s determination that the patents at issue were invalid for lack of written description under 35 U.S.C. § 112.
In 2017, Mylan filed an Abbreviated New Drug Application (ANDA) on a generic dimethyl fumerate (DMF) product for treating multiple sclerosis (MS). Biogen, the owner of the patent for the brand-name DMF product, Tecfidera®, sued Mylan for patent infringement, asserting six patents. Only one of those patents, U.S. Patent No. 8,399,514 (the ’514 Patent) was at issue on appeal.
The ’514 Patent claims a method for treating MS and claims priority to U.S. Provisional Application 60/888,921 (the ’921 Application). The ’514 Patent’s specification largely tracks that of the ’921 Application, which focuses primarily on drug discovery for a myriad of neurological disorders, rather than a method of treatment for a single such disorder, like MS. It contains a single paragraph related to dosage. The specific dosage used by Biogen in Tecfidera®, 480 mg/day (DMF480) is mentioned in this paragraph being at the bottom end of an exemplary range of effective therapeutic doses.
After a four-day bench trial the district court found that the specification did not reasonably describe to a person of ordinary skill in the art (POSA) that the inventors of the ’514 Patent had actually invented a method for treating MS with a therapeutically effective dose of DMF480 as of the date of the ’921 Application. The district court rejected Biogen’s argument that a POSA would be “drawn” to the DMF480 dose after reading the specification. Biogen appealed.
The Federal Circuit noted that the core issue on appeal was whether the ’921 Application’s specification described “possession” of the therapeutically effective DMF480-dose limitation to treat MS. The Court held that the district court did not clearly err in finding that it did not. In particular, the Court found the single reference to DMF480 to be a significant fact cutting against Biogen’s case, particularly because it only appeared at the end of one range listed along with a series of ranges and was never referenced independently. Additionally, the Court rejected Biogen’s ancillary arguments, finding they were rendered superfluous by the Court’s primary conclusion. As such, the Court affirmed the district court’s finding.