Merck Sharp & Dohme Corp. v. Hospira, Inc.

Case Name:  Merck Sharp & Dohme Corp. v. Hospira, Inc. 874 F.3d 724, No. 17-1115, 2017 U.S. App. LEXIS 21201 (Fed. Cir. Oct. 26, 2017) (Circuit Judges Newman, Lourie, and Hughes presiding; Opinion by Lourie, J.; Dissent by Newman, J.) (Appeal from D. Del., Andrews, J.) 

Drug Product and Patent(s)-in-Suit: Invanz® (etrapenem); U.S. Patent No. 6,486,150 (“the ’150 patent”)

Nature of the Case and Issue(s) Presented: The ’150 patent is directed to a process for preparing a stable formulation of ertapenem, an antibiotic compound. Ertapenem is known to be unstable because of two degradation reactions: hydrolysis of the lactam nitrogen and dimerization via the pyrrolidine nitrogen. The prior art taught that ertapenem could be stabilized from dimerization by reacting the pyrrolidine nitrogen with carbon dioxide to form a “carbon dioxide adduct.” The method of the ’150 patent claims a manufacturing process for a final formulation of the antibiotic that purportedly minimizes both dimerization and hydrolysis degradation pathways.

The district court found that, while none of the steps of claim 21 of the ’150 patent was individually taught by the prior art, the “recipe” for the final formulation was disclosed and the steps leading to that formulation were nothing more than conventional manufacturing steps that would have been obvious from the disclosures and thus were the product of routine experimentation. The district court found that the prior art expressly taught that the formation of the carbon dioxide adduct was pH-dependent and required a pH range of about 6.0 to about 9.0; sodium hydroxide could be used to adjust the pH; and the carbon dioxide adduct could be produced using “standard lyophilization techniques.” The district court also found that Merck “focused entirely on the validity of claim 21” and thus did not provide evidence rebutting Hospira’s expert’s testimony that each of the dependent claims’ narrower limitations was either expressly disclosed by the references or would have been obvious from routine experimentation. Finally, while evidence of commercial success and copying by others was shown, it could not overcome the strong prima facie case of obviousness.

Merck appealed and the Federal Circuit affirmed.

Why Hospira Prevailed:  On appeal, Merck argued that the district court erred because it was undisputed that none of the claimed steps was disclosed in the prior art. Merck argued that it was error to rely solely on the “knowledge, creativity, and common sense” of a skilled artisan because “common sense” is properly invoked to provide a motivation to combine, not to supply a missing claim limitation. Furthermore, Merck argued that the prior art focused solely on degradation by dimerization, not hydrolysis. The Federal Circuit did not agree, finding that the district court’s findings were supported by substantial record evidence. The Federal Circuit also dismissed Merck’s argument that the specific order and detail of the claimed steps constituted a novel solution to minimizing degradation by hydrolysis because, while that may have been so, the purported “solution” constituted nothing more than conventional manufacturing steps that implemented principles disclosed in the prior art.

Next, the Federal Circuit addressed the district court’s findings concerning secondary considerations. Merck argued that the district court improperly discounted objective evidence, which it found to be persuasive. The Federal Circuit found that the district court’s commercial-success finding was weakened by the “blocking effect” of another patent, which was directed to ertapenem itself. Thus, commercial success was not due to the qualities of ertapenem, but rather to the fact that Merck had control of another patent that precluded competition from others. With respect to the district court’s finding of copying by others because Hospira tried five alternative formulations in an attempt to design around, the Federal Circuit explained that evidence of copying is relevant in a Hatch-Waxman case, but that, as in commercial cases, Merck could not overcome the weight of the competing evidence of obviousness of the claimed process.

In her dissent, Judge Newman sought to “remedy our inconsistent treatment of the procedures and burdens in applying the evidentiary factors of obviousness, despite the clarifying precedent in Graham v. John Deere Co., 383 U.S. 1. 86 S. Ct. 684.” Judge Newman noted that some Federal Circuit decisions “appear to have sought a shortcut, and converted three of the four Graham factors into a self-standing ‘prima facie’ case, whereby the objective considerations must achieve rebuttal weight.” Here, it was error for the district court to weigh the evidence of secondary considerations against the conclusion that the order and detail of the claimed steps would have been discovered by routine experimentation. “I would reestablish the proper analytic criteria under the four Graham factors, and would remand to the district court to apply the correct law.”