Patent challenger Bass wins another review bid, this time on Acorda's Ampyra

Kyle Bass

So far, pharma patent challenger Kyle Bass and his Coalition for Affordable Drugs have met with some failure and some early success. On Friday, it was another mixed bag--but this time it's Acorda Therapeutics ($ACOR) that could face the consequences.

The Patent Trademark Office's Patent Trial and Appeal Board (PTAB) has decided to institute inter partes review on four of the patents covering multiple sclerosis drug Ampyra, the Ardsley, NY-based company's key product, Evercore ISI analyst Mark Schoenebaum wrote in a note to clients. Now, the case is set for a review, with a ruling on the patents expected in about one year.

It's a blow to Acorda--and a decision that could make the rest of pharma a little nervous, too. Some of short-seller Bass' early attempts to upturn pharma patents--a quest he claims is meant to lower drug prices for the good of society, though it also happens to make him money--have flatlined, and two Ampyra challenges were among them.

But Bass has maintained that he's not backing down, and his latest victory proves it. He filed the four IPRs now set for review shortly after receiving the Ampyra setback--and two of them are the original ones the board denied, submitted with more documentation to help make his case.

"I've spent years of my life working on this and my arguments are as good as can be," Bass told the Wall Street Journal at the time. "I think I can win if they'll just hear the cases on the merits."

That's not to say everything's coming up roses for Bass, though. Also Friday, the PTAB announced it had shut down a request to review one of the patents on Amgen's ($AMGN) Enbrel, set for expiration in 2029. But Amgen can hardly breathe easy: The FDA has already accepted an application from Novartis' ($NVS) Sandoz for an Enbrel biosimilar, and in March, the company targeted the Swiss drugmaker with a patent infringement suit.

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