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Court Reverses Summary Judgment of Inherent Anticipation

August 30, 2002

Decision icon Decision

Last Month at the Federal Circuit - September 2002

Judges:  Newman (author), Gajarsa, and Dyk (dissenting)

In Elan Pharmaceuticals, Inc. v. Mayo Foundation for Medical Education and Research, No. 00-1467 (Fed. Cir. Aug. 3, 2002), the Federal Circuit reversed the district court’s SJ in favor of the Mayo Foundation for Medical Education and Research (“Mayo”), holding two patents owned by Elan Pharmaceuticals, Inc. (“Elan”), U.S. Patent Nos. 5,612,486 (“the ‘486 patent”) and 5,850,003 (“the ‘003 patent”) invalid as anticipated by U.S. Patent No. 5,455,169 (“the Mullan patent”).

Elan’s ‘486 and ‘003 patents are directed to transgenic animals whose genetic makeup has been altered so that they are susceptible to Alzheimer’s disease. The DNA of these animals has been modified to contain a mutated human gene, which expresses amyloid precursor proteins (“APP”) containing the “Swedish mutation.” This mutation is believed to cause abnormal production of a protein fragment called beta-amyloid peptide (“betaAP”), which is formed when enzymes in the brain cleave APP. BetaAPs foster the formation of plaque deposits on the brain that cause Alzheimer’s disease.

Elan’s ‘486 and ‘003 patents claim transgenic rodents possessing human APP having the Swedish mutation wherein the APP is processed to ATFbetaAPP, a larger protein precursor to betaAPP, in sufficient amounts to be detectable. Detection of the larger ATF-betaAPP protein is easier than detection of betaAPP itself.

The prior art Mullan patent describes the isolation of the Swedish mutation and states that transgenic animals containing the mutated gene can be used in Alzheimer’s disease research and therapy. Specifically, the Mullan patent states that the mutated gene can be transferred to a mouse that preferably will express the mutated gene. The Mullan patent also discloses various known procedures of gene transfer and cites scientific articles as to each “approach” used to create transgenic animals. The Mullan patent did not mention ATF-betaAPP, produce a transgenic animal with the Swedish mutation, or determine which of the known procedures would be effective for this purpose. Moreover, experts for both Elan and Mayo testified as to the difficulty, uncertainty, unpredictability, and low success rate of the methods described in the Mullan patent to create transgenic animals.

The district court had found that although the Mullan patent does not mention the formation of ATF-betaAPP, its formation is inherent in the Mullan patent’s general teachings of transgenic mice with the Swedish mutation. The district court had found that the standard procedures set forth in the Mullan patent would be expected to produce a statistically small percentage of transgenic mice, and some of these mice would be expected to produce detectable ATF-betaAPP. Ruling that Elan’s claims did not require the claimed mice be tested for detectable ATF-betaAPP, the district court had found that the Mullan patent anticipates the claims.

On appeal, Elan argued that the Mullan patent does not mention producing detectable ATF-betaAPP, the critical limitation of its patent claims. Elan maintained that the Mullan patent does no more than teach broad known “recipes” for gene transfer and that the Mullan patent’s disclosure is simply an invitation to experiment with no assurance of success. In response, Mayo echoed the district court, arguing that the detectable ATF-betaAPP limitation is inherent in the Mullan patent because a successful transgenic procedure and ensuing enzymatic cleavage will produce detectable ATF-betaAPP.

The Federal Circuit agreed with Elan, finding that the Mullan patent did not describe every element of the Elan claim or teach, in terms other than trial and error and hope, production of a transgenic mouse having detectable ATF-betaAPP. The Federal Circuit concluded that there was no evidence that the formation and detection of ATF-betaAPP in the transgenic mouse brain with the Swedish mutation was known to persons of ordinary skill in the field of the invention, and inherency cannot be based on the knowledge of the inventor.

Judge Dyk dissented, arguing that the majority’s decision contradicts the case law and permits applicants to patent existing inventions by identifying inherent characteristics not identified in the prior art. In response, the majority stated that Elan did not patent something that previously existed because Elan’s mouse did not exist.