Biogen faces multibillion-dollar Tecfidera loss if Mylan wins latest patent threat

Cash cow Tecfidera has been pumping out blockbuster sales as Biogen plows ahead with pricey Alzheimer's trials and scouts for new pipeline assets. But what if those sales took a big hit early next year, instead of eight years later? That's the threat from a Mylan challenge at the U.S. Patent and Trademark Office, which just decided to put a 2028 Tecfidera patent under inter partes review. The Patent Trial and Appeals Board will hear arguments over the multiple sclerosis drug's '514 patent, with a decision due early next year.
Biogen's top drug by sales, Tecfidera brought in $4.27 billion last year. The company disclosed the patent review in its annual report Wednesday. The '514 patent is “vital” to the Tecfidera franchise as its others expire this year and next year, Leerink analyst Geoffrey Porges wrote in a Wednesday note to investors. Biogen has fought off one previous IPR challenge on the drug.