(Adds background to case, paragraphs 3-9)
By Andrew Chung
WASHINGTON, Oct 7 (Reuters) - The U.S. Supreme Court on Monday declined to hear Acorda Therapeutics Inc's appeal of a lower court ruling that allowed generic versions of its multiple sclerosis treatment Ampyra and caused the drug's sales to plummet.
The justices refused to review a September 2018 decision by the U.S. Court of Appeals for the Federal Circuit to cancel Acorda's patents covering Ampyra, a ruling the Ardsley, New York-based company and the pharmaceutical industry portrayed as a threat to innovation and bad for patients. The court's action came on the first day of its new term.
According to Acorda, Ampyra was the first drug approved to improve walking in people with multiple sclerosis, an incurable and potentially disabling disease of the brain and spinal cord that can lead to symptoms including pain, visual impairments and difficulty walking.
Acorda's patents covered how to treat patients with a medicine that was first identified in 1902.
Acorda in 2014 sued units of London-based Hikma Pharmaceuticals PLC, Pennsylvania-based Mylan NV , and Israel-based Teva Pharmaceutical Industries Ltd , which were planning generic versions of Ampyra.
The Federal Circuit, a specialized patent court located in Washington, last year invalidated four of the five patents protecting Ampyra from competition. The appeals court said the four canceled patents were not entitled to legal protection because they were obvious when compared to the fifth patent, which preceded them. That fifth patent expired in July 2018.
According to regulatory filings, Acorda's sales of Ampyra for the six-month period ending June 30 dropped 67 percent to $84.7 million compared to the same period last year.
At issue in the case is the Federal Circuit's view that certain pre-existing patents can make it easier to find that later patents based on them are obvious and thus invalid, even if those patents led to commercial success or addressed an unmet need in patients.
Acorda told the justices that this view "impairs patent rights and deters innovation." A group of drug companies including Allergan Plc filed a brief backing Acorda. (Reporting by Andrew Chung; Editing by Will Dunham)