Saying "But I won't do it" is not sufficient to avoid infringement in a Hatch-Waxman litigation, according to the Federal Circuit in the recently decided Sunovion Pharmaceuticals, Inc. v. Teva Pharmaceuticals USA, Inc. The ANDA applicant in that case was applying to market a generic version of Lunesta®, a chiral drug sold as a sleep medication. The lower court had construed one of the claims to require "less than 0.25%" of an unwanted chemical entity. However, the ANDA applicant was seeking to market a drug with "not more than 0.6%" of this chemical entity, which as the Court pointed out, is between 0.0-0.6%. Therefore, even though the ANDA applicant had submitted a declaration to the District Court (but not the FDA) vowing that it would only market its generic product with levels of this chemical entity at 0.3-0.6%, the Federal Circuit still found that the ANDA application had infringed for purposes of 35 U.S.C. § 271(e)(2). "What a generic applicant asks for and receives approval to market, if within the scope of a valid claim, is an infringement." As the Federal Circuit suggested, instead of telling a Court that it would not infringe a patent should it get approval to market it generic product, an ANDA applicant in such a case should instead amend its ANDA application to avoid infringement.
As background, Sunovion owns the rights in U.S. Patent No. 6,444,673 ("the '673 patent"), which claims the single-enantiomer drug eszopiclone. For those readers not up on chiral chemistry, chemical entities with, for example, a carbon atom and four different substituent atoms can assume two different structures that look similar but are not superimposable. The classic example used to illustrate this is your left and right hands. Instead of being superimposable, they are mirror images of each other. For chemical entities, the two different entities are called stereoisomers, and each individual stereoisomer is referred to as an enantiomer. One enantiomer is termed the dextrorotatory or (S)-enantiomer, while the other is termed the levorotatory or (R)-enantiomer. In the case of the '673 patent, the dextrorotatory entity is claimed, as shown in representative claim 1:
1. 6-(5-chloro-2-pyridyl)-5-[(4-methyl-1-piperazinyl)carbonyloxy]-7-oxo-6,7-dihydro-5H-pyrrolo[3,4-b]pyrazine, or a pharmaceutically acceptable salt thereof, in the form of its dextrorotatory isomer and essentially free of its levorotatory isomer.
Lunestra® is, of course, the dextrorotatory isomer, and the FDA required it contain no more than 0.3% of levorotatory isomer, referred to as (R)-zopiclone.
Dr. Reddy's Laboratories, Ltd. and Dr. Reddy's Laboratories, Inc. (collectively "Dr. Reddy") submitted an ANDA to market a generic version of Lunestra®, which included a Paragraph IV certification to the '673 patent. In turn, Sunovion sued Dr. Reddy pursuant to 35 U.S.C. § 271(e)(2). The District Court construed the claim term "essentially free" to mean "less than 0.25% of [the] levorotatory isomer." Dr. Reddy's initial ANDA application included the levels of the levorotatory isomer to be "[n]ot less than 0.3% and [n]ot more than 1.0%." The FDA required Dr. Reddy to tighten this limit to not more than 0.3%. Instead, Dr. Reddy amended its application to recite not more than 0.6% of the levorotatory isomer. The Federal Circuit opinion suggested that Dr. Reddy's generic product had not yet received approval. Nevertheless, as indicated above, Dr. Reddy "certified" to the lower court that it would not market any drug product that contained less than 0.3% of the levorotatory isomer, even though the FDA had suggested that it would not allow approval of such a limitation. In addition, the lower court accepted the fact that Dr. Reddy's internal manufacturing guidelines resulted in a level of levorotatory isomer that was more than 0.3%. Therefore, the lower court granted a summary judgment motion of noninfringement.
Sunovion first challenged the construction of the term "essentially free," which it thought should be defined as "largely but not wholly free" of the levorotatory isomer. This claim term was not defined in the specification, but according to the Court it was used more than once in the prosecution history to mean "less than 0.25%." One of these times, the applicants had stated that the disclosure of Example 1 was evidence of material that "consists essentially of" the dextrorotatory isomer. Of course, even though this phase does have the word "essentially" in it, the phrase "consists essentially of" has a particularized meaning in patent parlance. It should, therefore, not be evidence of what the applicants' thought to term "essentially" meant, at least with regard to the levorotatory isomer. However, the applicants also submitted a declaration during prosecution in which it was stated that the "pure form" of the dextrorotatory isomer "as described in Example 1" contained "lower than 0.25%" of the unwanted stereoisomer. This declaration was used in a subsequent interference as support for the term "essentially free" to be equated with containing less than 0.25% levorotatory isomer. The Federal Circuit found that the "applicants' repeated and consistent attribution of the purity level of less than 0.25% levorotatory isomer to 'the invention' and the 'the instant invention' thus gives meaning to the term 'essentially free.'" Accordingly, the Court affirmed the lower court's claim construction.
Sunovion, nevertheless, also argued that even with the lower court's construction of this claim term, Dr. Reddy also infringed. As indicated above, the Federal Circuit agreed, because Dr. Reddy was seeking approval to market a generic version of the drug that could fall within the scope of the asserted claims. The Court was not impressed with the internal manufacturing guidelines or the "certification" made to the court below. Instead, "the ultimate infringement question is determined by traditional patent law principles . . . ." The Court believed that allowing an ANDA applicant to avoid infringement based on "unconventional and unenforceable 'guarantee[s]'" while seeking to market a product that fell with the scope of asserted claims "would be incompatible" with those principles.
Dr. Reddy tried to rely on the Federal Circuit cases of Bayer AG v. Elan Pharmacetuical Research Corp., 212 F.3d 1241 (Fed. Cir. 2000), and Glaxo, Inc. v. Novopharm, Ltd., 110 F.3d 1562 (Fed. Cir. 1997). However, in both of those cases, the Court had found that the ANDA product described in the application fell outside the scope of the patents at issue. In fact, in Bayer, the NDA holder had based its infringement contention on a particular biobatch received from the ANDA applicant, which when tested fell within the scope of the claims. However, the Court in that case noted that the biobatch did not fall within the specification of the ANDA application, and therefore was irrelevant for purposes of infringement under § 271(e)(2). The present case presents almost the converse issue -- the ANDA applicant is asserting that the product it will market will fall outside the scope of the claim, but this is contrary to what the ANDA application teaches. "[Dr.] Reddy's ANDA specification clearly describes a product that meets the limitations of the asserted claims." Correspondingly, the Federal Circuit reversed the lower court's judgment of noninfringement.
Sunovion Pharmaceuticals, Inc. v. Teva Pharmaceuticals USA, Inc. (Fed. Cir. 2013)
Panel: Circuit Judges Lourie, Schall, and Reyna
Opinion by Circuit Judge Lourie