(October 20, 2016, 12:28 PM EDT) -- ALEXANDRIA, Va. — Three petitions for inter partes review (IPR) of patents covering the immunosuppressant drug natalizumab — marketed under the brand name “Tysabri” — were denied Oct. 17 by the Patent Trial and Appeal Board (Swiss Pharma International AG v. Biogen IDEC, No. IPR2016-00912, PTAB)....