In a win for Mallinckrodt, the Patent Trial and Appeal Board (PTAB) invalidated BioVie’s patent on a treatment for ascites — an accumulation of abdominal fluid often linked to advanced liver cirrhosis.

Mallinckrodt challenged the patent on methods for treating ascites with the peptide drug terlipressin on the grounds that the method was widely known at the time BioVie filed for the patent in 2015.

In the inter partes review, BioVie argued that Mallinckrodt failed to show a reasonable likelihood that the patent would be obvious or anticipated based on prior art.

But PTAB found that the prior art described using terlipressin  for “treating a patient diagnosed with ascites due to liver cirrhosis.” The board similarly found that 15 claims were unpatentable. Based on the  prior art, “an ordinarily skilled artisan would have had a reason to combine the teachings” to arrive at the challenged claims, PTAB said.