ANDA Product Controls Infringement Analysis In Hatch-Waxman Framework

Last week, the Federal Circuit, in Sunovion Pharm. v. Teva Pharm. USA, et al., addressed the appropriate infringement analysis in the context of Hatch-Waxman (aka “ANDA”) litigation. It held:

Although no traditional patent infringement [occurs] until a patented product is made, used, or sold, under the Hatch-Waxman framework, the filing of an ANDA itself constitutes a technical infringement for jurisdictional purposes. But the ultimate infringement question is determined by traditional patent law principles and, if a product that an ANDA applicant is asking the FDA to approve for sale falls within the scope of an issued patent, a judgment of infringement must necessarily ensue.

Id., No. 2013-1335, slip op at 11-12 (Fed. Cir. Sept. 26, 2013) (citations omitted) (emphasis added).

Sunovion Pharmaceuticals, Inc. (“Sunovion”) owns the rights to U.S. Patent 6,444,673 (“the ‘673 patent”), which is directed to pharmaceutical compositions of the drug eszopiclone, the dextrorotatory, or (S)-enantiomer form of zopiclone, and specifically claims the dextrorotatory isomer of zopiclone “essentially free of its levorotatory isomer.” Id. at 3. The ‘643 patent is listed in the FDA’s Approved Drug Products  with Therapeutic Equivalence Evaluation (aka, the “Orange Book”) in reference to Sunovion’s marketed sleep medication Lunesta®.

Dr. Reddy’s Laboratory (“DRL”), pursuant to 21 U.S.C. § 355(b)(1), filed an Abbreviated New Drug Application (“ANDA”) with a certification under 355(j)(2)(A)(vii)(IV) (the “DRL Para. IV”) seeking approval to market a generic version of Lunesta®. Sunovion brought the underlying suit against DRL alleging that DRL’s ANDA constituted an act of infringement of the ‘673 patent under 35 U.S.C. § 271(e)(2)(A).

During claim construction, the District Court construed “essentially free” to mean “less than 0.25%” of the levorotatory enantiomer, (R)-zopiclone. This is significant because in approving the product for market, the FDA specifically required that each tablet of Lunesta® contain not more than 0.3% of the levorotatory enantiomer. Id. at 3-4. The District Court’s construction meant that products containing not less than 0.25% and not more than 0.3% would be outside the scope of the ‘673 patent, but within the acceptable limits for a marketed eszopiclone product as required by the FDA.

DRL, in its original ANDA, sough approval of generic eszopiclone products with not less than 0.3% and not more than 1.0% levorotatory isomer. Id. at 5 (citations omitted). Pursuant to a request by the FDA to tighten the limits of the levorotatory isomer, DRL revised its ANDA to seek approval of generic products limited to not more than 0.6% of the levorotatory isomer. Id. DRL then moved for summary judgment of noninfringement.

The District Court initially denied DRL’s motion, but permitted DRL to file a renewed motion for noninfringement provided that DRL provide a certification that it will not market a eszopiclone product that contains less than 0.3% of the levorotatory isomer. DRL submitted a declaration representing that it would only manufacture products for market containing 0.3%-0.6% of the levorotatory isomer. Based on that certification, the District Court granted DRL’s motion for summary judgment of noninfringement because the “products [DRL] presumes to market would likely be ‘outside the infringing range of less than 0.25% of levorotatory isomer.’” Id. at 6. Summary judgment was granted despite what DRL had identified as its proposed generic product in its amended ANDA.

The Federal Circuit reversed the District Court’s finding of noninfringement, despite affirming the claim construction of “essentially free” to mean “less than 0.25%” of the levorotatory enantiomer. It held that what DRL “asked the FDA to approve as a regulatory matter is the subject matter that determines whether infringement will occur.” Id. at 12. If DRL’s proposed ANDA product falls within the scope of a valid claim, it is infringement. Id. at 13. Furthermore, a party cannot avoid infringement by providing representations or offering guarantees that it will stay outside the scope of the claims should it be granted market approval when what it has asked the FDA to approve in its ANDA is within the scope of the issued claims. Id. at 12-13, 15.

The Federal Circuit also rejected DRL’s argument that Sunovion could test DRL’s marketed product and bring suit if the product falls within the range of levorotatory isomer covered by the claims. The Court noted that the Hatch-Waxman process was enacted to specifically handle instances where a generic manufacturer files an ANDA seeking to copy an approved product, “and it therefore must comply with the definition of the approved product.” Id at 13 (citing 21 U.S.C. § 355(j)(4)(F); Pfizer Inc. v. Shalala, 182 F.3d 975, 977 (D.C. Cir. 1999)). Allowing ANDA defendants to avoid liability by simply stating “I won’t infringe” would delay the infringement determination that Hatch-Waxman litigation was penned to resolve before ANDA approval.

The take-away from this case is that unequivocally, under the Hatch-Waxman framework, “if an ANDA specification defines a compound such that it meets the limitations of an asserted claim, then there is almost never a genuine issue of material fact that the claim is infringed.” Id. at 14. It will be interesting to see if this decision leads to an increase in more summary judgment motions by Hatch-Waxman plaintiffs or stipulations on infringement (or noninfringement) in future cases.

Gibbons will continue to track future developments stemming from the decision of this case.