Enablement standard for prior art less stringent than enablement standard for patentsNovember 21, 2006

The Federal Circuit, in Impax Laboratories, Inc. v. Aventis Pharmaceuticals Inc., discussed the requirements for a prior art reference to be enabled, and thus anticipate a patent. Aventis is the owner of U.S. Patent No. 5,527,814, covering the use of the compound riluzole to treat ALS, commonly known as Lou Gehrig’s disease. Impax wanted to produce a generic version of riluzole,so it filed an abbreviated new drug application (ANDA) with the FDA. Impax also sued Avnetis for a declaration that the ‘814 patent was invalid and/or unenforceable. The district court sided with Aventis, findingthe ‘814 patent valid and enforceable and that Impax’s generic riluzole would infringe. The Federal Circuit vacated part of the lower court’s ruling on anticipation, and discussed the proper standard for enablement of a prior art reference.

More details of the court’s decision after the jump.

Impax presented two main prior art references it contended anticipated the ‘814 patent, a prior patent and the published application from which it issued. The district court held that neither of these references could invalidate the ‘814 patent because they did not enable one of ordinary skill in the art to use riluzole to treat ALS. This conclusion was based on a passage in the prior patent’s specification that the inventors did not consider riluzole to be part of the invention because it was known in the art at that time. Thus, the lower court concluded that one of ordinary skill “would not have recognized that riluzole was effective in treating ALS without additional detail” not found in the prior patent.

The Federal Circuit disagreed. Specifically, the court noted that the enablement standard for prior art is different from the enablement requirement under ? 112 of the patent act. Citing a prior case, the Federal Circuit noted that there is no requirement that a prior art reference provide proof that a particular compound is effective for the reference to be enabled under ? 102. Because the lower court’s decision relied upon no proof of efficacy to support its conclusion of nonenablement, the court vacated that portion of the decision and remanded for the district court to further consider the issue. With regard to inequitable conduct, the Federal Circuit affirmed the finding that no inequitable conduct existed in this case. Inequitable conduct occurs when, with intent to deceive the patent office, a patent applicant makes an affirmative misrepresentation of material fact, fails to disclose material information, or submits of false material information. The alleged inequitable conduct at issue was the alleged failure to disclose full test results regarding seven compounds that were tested for efficacy in treating ALS. Aventis disclosed the results of some of these tests (showing little efficacy in the tested compounds) to support its assertion of unexpected results of riluzole. The Federal Circuit agreed with the lower court that this lack of disclosure was not material, nor was is made with deceptive intent. Thus, the finding of no inequitable conduct was affirmed.

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