Where a claim was distinguished from the prior art only because it contained a limitation requiring "pharmaceutically effective absorption," the US Court of Appeals for the Federal Circuit affirmed an opinion from the US District Court for the District of New Jersey that such a claim was obvious, concluding that one of ordinary skill in the art would have been motivated to modify or combine the art to produce such a result. Warner Chilcott Co., LLC v. Teva Pharmaceuticals USA, Inc., No. 2015-1588 (March 18, 2016 Fed. Cir.) (Lourie, J.).

Warner Chilcott owned two patents claiming oral dosage forms comprising risedronate and ethylenediaminetetraacetic acid (EDTA), and methods for treating disorders characterized by abnormal calcium and phosphate metabolism, such as osteoporosis. Warner Chilcott's commercial embodiment of the patented invention is known as Atelvia® (risedronate sodium). Teva filed an abbreviated new drug application (ANDA) seeking approval of a generic version of Atelvia. In response, Warner Chilcott filed suit alleging infringement. Teva conceded infringement but asserted that Warner Chilcott's patents were invalid.

During a bench trial, the parties agreed that a prior art Brazilian patent application disclosed all limitations of the Warner Chilcott patent claims except for a limitation requiring "pharmaceutically effective absorption." In evaluating whether the Brazilian patent application disclosed that limitation, the district court concluded that the application taught using an amount of EDTA sufficient to bind ions in food, but only in an amount low enough that it would not significantly alter absorption. Thus, the district court did not find that the Brazilian reference inherently anticipated the Warner Chilcott patents. Nevertheless, the district court concluded that the Warner Chilcott patents were obvious because the "food-effect problem" affecting absorption had been "well explored in the literature," and numerous references explicitly taught that EDTA would increase absorption.

On appeal, Warner Chilcott argued that the district court misinterpreted the phrase "pharmaceutically effective absorption," and erroneously equated the invention with overcoming food effects. As a result, Warner Chilcott disputed the district court's finding of a motivation to modify the prior art to achieve the claimed invention.

The Federal Circuit affirmed the finding of obviousness, concluding that the Brazilian patent application nearly anticipated the claimed invention. Indeed, the Federal Circuit agreed that the only limitation lacking in the prior art was "pharmaceutically effective absorption." Noting that common sense suggests that any pharmaceutical composition entitled to a patent would have to be pharmaceutically effective, the Federal Circuit recognized that Warner Chilcott was able to overcome a rejection at the patent office by including this limitation referring to the fed/fasted absorption defined in the specification. Thus, the Federal Circuit agreed with the district court that the limitation logically referred to fed/fasted absorption as defined in the specification. The court further agreed with the district court that the prior art references  and teachings would have led one of ordinary skill in the art to use EDTA to sufficiently reduce or negate the food effect to obtain the claimed invention.

With respect to a claim directed to a specific amount of EDTA (100 mg), the court concluded that such a limitation to a specific amount was nevertheless obvious. The Federal Circuit reasoned that the specification included a broad disclosure, including embodiments with varying levels of EDTA, and nothing within the specification established that the specifically claimed amount resulted in "pharmaceutically effective absorption." Moreover, nothing within the specification suggested that the specific amount of EDTA was critical to the invention. As a result, the Federal Circuit affirmed the decision of the district court that the claims were invalid as obvious.

Federal Circuit Rejects Argument That Claim Is Novel because Composition Exhibits 'Pharmaceutically Effective Absorption'

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