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Enablement Standard Differs for 35 U.S.C. §§ 102 and 112

June 27, 2005

Decision icon Decision

Last Month at the Federal Circuit - July 2005

Judges: Bryson (author), Plager, and Prost

In Rasmusson v. SmithKline Beecham Corp., No. 04-1191 (Fed. Cir. June 27, 2005), the Federal Circuit affirmed a decision by the PTO Board, holding that Gary H. Rasmusson and Glenn F. Reynolds (collectively “Rasmusson”) could not defeat the prior date accorded to certain patents owned by SmithKline Beecham Corporation (“SmithKline”). However, the Federal Circuit reversed an aspect of the Board’s decision that had found a European patent application, EP No. 285383 (“the EP ‘383 application”), as not enabled for purposes of anticipation. Accordingly, the Court remanded this issue to the Board for determination of the effect of the EP ‘383 application on the claims of the patents and applications at issue at the PTO.

The case relates to a method of treating a type of prostate cancer by administering a chemical compound called finasteride, which inhibits the production of an enzyme known as 5-a-reductase (“5aR”).

Rasmusson’s U.S. Patent Application No. 08/460,296 (“the ‘296 application”) was filed on June 2, 1995, as the ninth in a series of applications going back to April 1987. SmithKline’s U.S. Patent No. 5,637,310 (“the ‘310 patent”) and 5,496,556 (“the ‘556 patent”) and their corresponding reissue applications (“the ‘310 reissue patent application” and “the ‘556 reissue patent application,” respectively), were accorded the benefit of the filing date of another issued patent, U.S. Patent No. 5,300,294 (“the ‘294 patent”), filed on June 27, 1990.

Given SmithKline’s June 1990 filing date, Rasmusson sought priority on the basis of his first, second, and third applications, going back to April 1987, May 1988, and June 1989, respectively. The Board found that Rasmusson was not entitled to such priority, because the corresponding applications failed to satisfy the written description and enablement requirements of 35 U.S.C. § 112.

On appeal, Rasmusson asserted that the respective applications are enabling because a person of ordinary skill in the art could perform the steps of the disclosed method for treating human prostate cancer without the need for any experimentation. While both parties agreed that one of ordinary skill in the art at the time of Rasmusson’s applications would have recognized that finasteride was a selective 5aR inhibitor, they disagreed as to whether one of ordinary skill in the art would have believed, before June 27, 1990, that finasteride would be effective for treating prostate cancer.

The Federal Circuit agreed with the Board that one of ordinary skill in the art would not have believed that finasteride was effective in treating prostate cancer simply because finasteride was known to be a selective 5aR inhibitor. The Board referred to evidence pertinent to each of Rasmusson’s relevant application filing dates from the mid-1980s to the mid-1990s to show that on each of those dates, it remained unclear in the art whether DHT or testosterone caused prostate cancer. If testosterone, and not DHT, caused the disease, then the antitumor effect resulting from multiactive 5aR inhibitors was not due to 5aR inhibition, but rather to antitestosterone mechanisms, such as the inhibition of testosterone recepter binding. The Board concluded that not until June 1995 would a person of ordinary skill in the art have believed that 5aR inhibition could play a role in treating prostate cancer. Accordingly, the Federal Circuit agreed with the Board that Rasmusson was not entitled to a priority date earlier than the priority date of SmithKline’s ‘310 and ‘556 patents in corresponding reissue applications.

In conjunction with filing his first application in the United States, Rasmusson also filed the EP ‘383, application, which was published on October 5, 1988. The Board found that the EP ‘383 application did not anticipate SmithKline’s claims at issue, because the EP ‘383 application lacked an enabling disclosure. The Federal Circuit ruled, however, that the standard for what constitutes proper enablement of a prior art reference for purposes of anticipation under § 102 differs from the enablement standard of § 112. The Court agreed with Rasmusson that proof of efficacy is not required in order for a reference to be enabled for purposes of anticipation. Accordingly, the Federal Circuit remanded the case to the Board to allow the Board to resolve the anticipation question in the first instance.