In Prometheus Laboratories, Inc. v. Roxane Laboratories, Inc., Appeal Nos. 2014-1634, 2014-1635, the Federal Circuit affirmed the district court’s invalidity judgment, concluding a pharmaceutical patent’s species claims would have been obvious over a prior art patent disclosing the genus.

Roxane submitted to the FDA a paragraph IV certification that its generic version of a drug would not infringe Prometheus’s patent on the treatment of women with diarrhea-predominant irritable bowel syndrome (IBS-D) utilizing the drug, or alternatively that the patent was invalid.  Prometheus sued Roxane for infringement.  The district court found the claims would have been obvious over a prior art patent that disclosed treating a condition such as IBS by administering to a patient an effective amount of the drug.

The Federal Circuit affirmed the judgment of invalidity based on obviousness.  The Federal Circuit reasoned that the claim “limitations are directed to a known type of IBS, to treating the gender that predominantly experiences IBS, to treating patients with a characteristic that is always or almost always evaluated in establishing IBS, and to assessing symptoms for a duration of time that was common in diagnosing patients with IBS.”  Thus, “it would have been obvious for a person having ordinary skill in the art reading the . . . [genus methods in the reference patent] to treat female patients with IBS-D who had symptoms for at least six months and who had experienced at least moderate pain.”  Recognizing that, even though “a narrow species can be non-obvious and patent eligible despite a patent on its genus,” the Federal Circuit nevertheless concluded that the disputed species claims would have been obvious over the reference patent and other prior art because the claimed patient subset did not display unexpected results.