'Teaching Away' Requires Clear Discouragement from Claimed Combination.

The U.S. Court of Appeals for the Federal Circuit found "clear error" in a district court ruling that a patent directed to an ophthalmic anti-inflammatory drug formulation, marketed by Allergan, Inc. (Allergan) under the brand name ACULAR[R], was valid and not an obvious variation of earlier known compounds. Syntex (U.S.A.) LLC v. Apotex, Inc., Case No. 04-1252 (Fed. Cir. May 18, 2005) (Gajarsa C.J.; Prost, C.J. concurring).

Apotex, Inc. (Apotex) appealed from the final judgment of the district court, which, after a bench trial, held the patent owned by Syntex LLC (Syntex) not invalid, enforceable and infringed by Apotex's Abbreviated New Drug Application (ANDA). The patent claims a formulation for sterile, preserved eye drops to treat eye inflammation, such as that caused by conjunctivitis or eye surgery, and teaches combining a nonsteroidal anti-inflammatory drug (NSAID) such as ketoralac tromethamine (KT) and a quaternary ammonium preservative such as benzalkonium chloride (BAC) with a surfactant such as octoxynol 40. The surfactant serves to prevent the two active ingredients from reacting with each other to form undesirable complexes.

On appeal, the critical issue was whether the use of the surfactant octoxynol 40 in the claimed formulations is an obvious alteration of similar formulations taught in the prior art. The Federal Circuit found clear error in the trial court's finding that "[n]o pharmaceutical formulation other than ACULAR[R] has ever included Octoxynol 40," particularly in view of a report that had issued five days after the priority date of the patent stating that octoxynol 40 was "well known . . . in pharmaceutical products." Furthermore, the Federal Circuit held that the prior art references did not "teach away" from the patented invention, noting a statement that a particular combination is not a preferred embodiment does not teach away absent clear discouragement of that combination.

The Federal Circuit also found error in the finding of a failure of proof that there would have been any motivation by one of ordinary skill in the art to use octoxynol 40 in the claimed formulations. The Court pointed to the district court's failure to examine expert testimony on the question of whether one of ordinary skill in the art would have deemed the invention obvious and, as a subset of the overall obviousness question, whether octoxynol 40 produced the unexpected results asserted by Syntex. Based on the prosecution history of the relevant patents, the Federal Circuit found reason to doubt the final examiner's conclusion that octoxynol 40 produced unexpected results sufficient to overcome a prima facie case of obviousness and pointed out that, in the parent application, a different examiner had been unconvinced by the same evidence. Finally, the Federal Circuit also said the lower court should reconsider the significance of Syntex's commercial success in light of its recent Merck v. Teva decision.

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