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Court Remands Issue of Obviousness for Patent Covering ACULAR

May 18, 2005

Decision icon Decision

Last Month at the Federal Circuit - June 2005

Judges: Gajarsa (author), Clevenger, and Prost (concurring)

In Syntex (U.S.A.) LLC v. Apotex, Inc., No. 04-1252 (Fed. Cir. May 18, 2005), the Federal Circuit reversed a judgment of no invalidity because it found that the district court had erred in establishing certain factual predicates to its nonobviousness determination.

After a bench trial, the district court held that U.S. Patent No. 5,110,493 ("the '493 patent"), owned by Syntex (U.S.A.) LLC ("Syntex"), was not invalid and was enforceable, and infringed by three Defendants' (collectively "Apotex") ANDA. Allergan, Inc., Syntex's distributor, has exclusive rights to manufacture the commercial embodiment of the '493 patent under the trademark ACULAR. The '493 patent claims eye drops used for treating eye inflammation. On April 25, 2001, Apotex notified Syntex that it had filed ANDA 76-109 with the FDA to market a generic version of ACULAR. Apotex stated that it believed the '493 patent to be invalid on the grounds of obviousness and inequitable conduct, and, therefore, it was not infringed by Apotex's proposed generic version of ACULAR. About six weeks later, Syntex filed suit for patent infringement.

After construing the claims, the district court ruled on SJ that Apotex had literally infringed the '493 patent claims. After a subsequent bench trial, the district court found that the claims were not invalid and were not unenforceable. On appeal, Apotex challenged the district court's conclusion that the claim term "in a stabilizing amount" should properly read as an effective limitation on the scope of the claim. The Federal Circuit agreed with the district court that this phrase described the intended result of using the weight-to-volume ratios recited in the claims. Having affirmed the claim construction, the Federal Circuit affirmed the finding of infringement.

Concerning obviousness, the issue on appeal was whether the use of the surfactant octoxynol 40 in the claimed formulations was an obvious alteration of similar formulations taught in the prior art. The Federal Circuit found that the district court had erred in finding that no pharmaceutical formulation other than ACULAR has ever included octoxynol 40 and in finding that several other references teach away from the use of octoxynol 40 in the claim formulations. Moreover, the Federal Circuit suggested that the district court did not appreciate that the prosecution history of the relevant patents, while not establishing inequitable conduct, cast some doubt on the Examiner's conclusion that the claimed surfactant produces unexpected results sufficient to overcome a prima facie case of obviousness. Finally, the Federal Circuit suggested that the district court should reconsider the significance of the commercial success of the patented formula in light of its recent decision in Merck & Co. v. Teva Pharmaceuticals USA, Inc., 395 F.3d 1364 (Fed. Cir. 2005).