Patent Case Summaries January 2, 2020

Patent Case Summaries | Week Ending December 27, 2019

A weekly summary of the precedential patent-related opinions issued by the Court of Appeals for the Federal Circuit and the opinions designated precedential or informative by the Patent Trial and Appeal Board.


Persion Pharmaceuticals LLC v. Alvogen Malta Operations Ltd., No. 2018-2361 (Fed. Cir. (D. Del.) Dec. 27, 2019). Opinion by Reyna, joined by O’Malley and Chen.

The Federal Circuit affirmed the district court’s judgment that Persion’s asserted patent claims were invalid as obvious. 

Persion sued Alvogen for patent infringement based on Alvogen’s Abbreviated New Drug Application seeking to market a generic version of Zohydro ER, Persion’s extended-release hydrocodone drug. The two patents-in-suit cover methods of using Zohydro ER to treat patients with mild to moderate hepatic impairment. After a bench trial, the district court found that the asserted claims were invalid as obvious and that the claims lacked sufficient written description.

On appeal, Persion argued that the district court erred by (1) improperly relying on inherency, (2) relying on evidence from formulations and patient groups not covered by the claims, (3) finding the claims obvious before considering Persion’s objective indicia of nonobviousness, and (4) finding obviousness in a manner that is internally inconsistent with the finding of lack of written description. The Federal Circuit rejected all four arguments.

First, the Federal Circuit ruled that the district court did not err by finding that the pharmacokinetic parameters of the asserted claims were inherent based on a combination of prior art references. The Federal Circuit explained that inherency may supply a missing claim limitation in an obviousness analysis, including where the limitation is “the natural result of the combination of prior art elements.” The district court therefore did not err in finding that the combined references “taught the combination of elements that inherently result in the claimed pharmacokinetic parameters.”

Second, the court rejected Persion’s improper-evidence argument, finding no clear error in the district court’s analysis.

Third, the Federal Circuit ruled that the district court properly considered Persion’s evidence of objective indicia of nonobviousness together with the other evidence, and did not treat it as a “mere afterthought.” This was true even though the district court listed its discussion of the objective indicia after its discussion of the prior art.

Finally, the Federal Circuit rejected Persion’s argument that the district court’s obviousness and written description discussions were internally inconsistent. Persion’s argument was “based on incomplete quotations from the district court’s opinion,” and “a complete reading … belies Persion’s assertion that the district court’s findings are inconsistent.”

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