
Shares of Biogen fell Thursday after a federal court judge ruled in favor of generic drug maker Mylan in a patent case involving the biotech’s top-selling multiple sclerosis drug, Tecfidera.
The U.S. District Court in West Virginia declared invalid Biogen’s so-called “514” patent protecting Tecfidera from generic competition. The ruling gives Mylan the right to launch its own version of Tecfidera within days, although Biogen said Thursday that an appeal will be filed.