Pledge Not To Infringe Cannot Override Conclusion Of Infringement Based On Seeking FDA Approval To Market Generic Compound Within Scope Of Valid Patent

In Sunovion Pharmaceuticals, Inc. v. Teva Pharmaceuticals USA, Inc., No. 13-1335 (Fed. Cir. Sept. 26, 2013), the Federal Circuit reversed the district court's grant of SJ of noninfringement, concluding that, although the district court did not err in construing the asserted claims, Sunovion Pharmaceuticals, Inc. ("Sunovion") was entitled to a judgment of infringement as a matter of law under 35 U.S.C. § 271(e)(2)(A).

U.S. Patent No. 6,444,673 ("the '673 patent"), owned by Sunovion, is directed to pharmaceutical compositions of the single-enantiomer drug eszopiclone, the active ingredient in the sleep medication marketed as Lunesta®. The claim recites that the compound is "in the form of its dextrorotatory isomer," i.e., eszopiclone, and "essentially free of its levorotatory isomer." Slip op. at 3 (citation omitted). In approving Lunesta®, the FDA required that each tablet contain not more than 0.3% of eszopiclone's corresponding levorotatory enantiomer. The '673 patent is listed in the FDA's publication known as the Orange Book.

Dr. Reddy's Laboratories, Ltd. and Dr. Reddy's Laboratories, Inc. (collectively "Reddy") submitted to the FDA an ANDA including a paragraph IV certification with respect to the '673 patent, seeking approval to market generic eszopiclone tablets prior to the expiration of the '673 patent. Sunovion sued Reddy for patent infringement under 35 U.S.C. § 271(e)(2)(A). Reddy's original ANDA specification requested approval for generic eszopiclone products with not less than 0.3% and not more than 1.0% of the levorotatory isomer, but the FDA required Reddy to "tighten up" the levorotatory limit to not more than 0.3%. In response, Reddy revised its ANDA specification to restrict the levorotatory limit to not more than 0.6%.

Following a Markman hearing, the district court construed the claim term "essentially free" to mean "less than 0.25% of [the] levorotatory isomer" based on an inventor's declaration and the prosecution history. Id. at 4 (alteration in original) (citation omitted). Reddy moved for SJ of noninfringement. The district court initially denied Reddy's motion, but then permitted Reddy to file a renewed motion for SJ of noninfringement accompanied by a "certification" that Reddy would not market an eszopiclone product containing less than 0.3% of the levorotatory isomer. Reddy submitted a declaration from one of its employees vowing to the district court, but not to the FDA, that Reddy would only market generic...