UCB, Inc., et al. v. Accord Healthcare, Inc., et al., No. 16-2610 (Fed. Cir. May 23, 2018)
In a 2-1 decision, the Federal Circuit upheld the District of Delaware’s finding that the asserted claims of the ’551 patent covering lacosamide (Vimpat®) are not invalid for obviousness-type double patenting, obviousness, and/or anticipation. The holding in UCB reaffirms the long-held notion that structural obviousness of chemical composition claims remains one of the most challenging defenses for defendants. The opinion was filed by Judge Stoll and joined by Judge Bryson, with Chief Judge Prost dissenting.
Of particular note, the Federal Circuit clarified the obviousness-type double patenting analysis to be applied to chemical compounds, “In chemical cases, the double patenting inquiry is not whether a person of ordinary skill in the art would select the earlier compound as a lead compound, but rather whether the later compound would have been an obvious or anticipated modification of the earlier compound.” UCB, Inc., No. 16-2610, slip op. at 16. Further stating, “the focus of the double patenting analysis entails determining the differences between the compounds claimed in the reference and asserted patents and then ‘determining whether those differences render the claims patentably distinct.’” Ibid at 17.
Acknowledging a “close case,” the majority found no clear error in the District Court’s finding that the asserted claims were patentably distinct from the reference claims of the ’301 patent. The majority found that a person of ordinary skill in the art would not have had a reasonable expectation of success that the changes required to obtain the compounds of the ’551 patent would have yielded an efficacious anticonvulsant. The majority pointed to the lack of data to provide “sufficient insight into the effectiveness” of making the required changes.
In dissent, Chief Judge Prost found that the District Court erred, in part, by dismissing certain prior art data. Both the District Court and the majority credited plaintiff’s expert that the available prior art data was not useful to the person of ordinary skill in the art. While too detailed for this summary, the specifics of the majority’s holding and Chief Judge Prost’s dissent are a worthwhile read for those interested in structural obviousness.
With regard to the obviousness of the claims, the Federal Circuit upheld the District Court’s finding that the asserted claim covering lacosamide were not obvious over the prior art racemate because a person of ordinary skill in the art would not have chosen to develop the racemate based on the data known in the art at the time. The Federal Circuit also clarified that “[a] lead compound analysis is not required in analyzing obviousness of a chemical compound when, in the inventing process, there was no lead compound. . . . We are not aware of any authority holding that a lead compound analysis is or is not required in cases involving purifying mixtures.” Ibid at 26-27.
The Federal Circuit also reaffirmed its holding that a racemic mixture of chemical compounds (i.e., identical quantities of both enantiomers) does not anticipate a claim directed to a single enantiomer. “[T]he knowledge that enantiomers may be separated is not ‘anticipation’ of a specific enantiomer that has not been separated, identified, and characterized.” Ibid at 28-29.