The U.S. Court of Appeals for the Federal Circuit struck a blow Nov. 30 to Biogen Inc.’s blockbuster multiple sclerosis (MS) drug, Tecfidera, affirming a lower court’s determination that a patent claiming a method of treating MS was invalid for lack of written description. In two other precedential cases the next day, the appellate court opened the door for Arbutus Biopharma Corp. to seek royalties on Moderna Inc.’s COVID-19 vaccine.