Patent Challenge to Alexion Proceeds, But No Amgen Biosimilar Yet

Three patents that extend the exclusivity of Alexion Pharmaceuticals’ franchise rare disease drug will now face a patent challenge from Amgen.

On Friday, a court within the US Patent and Trademark Office agreed to a review of Amgen’s claims that three Alexion (NASDAQ: ALXN) patents covering its drug, eculizumab (Soliris), were anticipated or obvious, and are therefore invalid. The announcement from the Patent Trial and Appeals Board kicks off a court proceeding that could take up to one year to decide.