In a pair of opinions, both issued as Ferring B.V. v. Watson Laboratories, Inc., the Federal Circuit held that Watson’s and Apotex’s ANDA products will not infringe Ferring’s patents covering Lysteda, a tranexamic acid treatment for menorrhagia, or heavy menstrual bleeding in women. The cases had been consolidated at the district court level, where the District of Nevada found that Watson’s ANDA products would infringe, but dismissed Ferring’s claims against Apotex as moot in light of an amendment to Apotex’s ANDA that rendered it non-infringing.

In Ferring’s appeal, the Federal Circuit affirmed the district court’s dismissal of Ferring’s claims. The infringement dispute concerned the claimed dissolution rates of tranexamic acid in water. Ferring’s patents claimed dissolution rates of “less than about 70% by weight tranexamic acid . . . released at about 45 minutes and not less than about 50% by weight . . . released by about 90 minutes.” Apotex’s 2010 ANDA specified that at least 80 percent by weight of tranexamic acid would dissolve in 60 minutes. At trial on infringement, the district court found that Apotex’s ANDA permitted sale of an infringing product because the ANDA was silent as to the weight percent of drug released at the times specified in the patents-in-suit. After trial, Apotex amended its ANDA to specify that “not less than 75% by weight of tranexamic acid would be dissolved at 45 minutes,” a dissolution rate which the district court suggested at trial would not infringe. In light of the proposed ANDA amendment, the district court dismissed the case, and Ferring appealed the issue of whether either the 2010 ANDA or the amended ANDA infringed.

The Federal Circuit affirmed the dismissal of Ferring’s claims based on the amended ANDA, but found that the district court improperly held that the 2010 ANDA infringed because Apotex could infringe under the terms of the ANDA, reasoning that the ANDA must still clearly describe a product that meets the limitations of the asserted claims in order to infringe.

“When an ANDA is silent with respect to infringement, as is the 2010 ANDA, the correct analysis is under Glaxo, . . . not Sunovion. . . . In Glaxo, the patent-holder argued, as Ferring does here, that ‘the alleged infringer must disprove infringement if the ANDA permits sale of a composition that may include an infringing product.’ We disagreed and concluded that ‘[t]he relevant inquiry is whether the patentee has proven by a preponderance of the evidence that the alleged infringer will likely market an infringing product. What is likely to be sold, or, preferably, what will be sold, will ultimately determine whether infringement exists.’ For the patent-holder to prove that a Glaxo-type ANDA is infringing, it must rely on evidence that the ANDA applicant ‘would likely sell an infringing composition pursuant to an approved ANDA.’”

Applying Glaxo, the Court found that Ferring failed to show that Apotex would likely sell an infringing product and that the district court erred in finding that the 2010 ANDA was infringing.

The Court likewise applied Glaxo in Watson’s appeal, reversing the district court’s infringement ruling. After clarifying that § 271(e) cannot be read to mean that the act of filing an ANDA itself could establish infringement without consideration of the ANDA specification or amendments thereto, the Court explained that an ANDA specification may resolve the infringement question when it “defines a proposed generic product in a manner that either meets the limitations of an asserted patent claim or is outside the scope of such a claim.” Where the ANDA specification is silent on infringement, the district court should refer to relevant evidence, “including biobatch data and actual samples of the proposed generic composition that the ANDA filer had submitted to the FDA.”

Because Watson’s ANDA did not resolve the question of infringement, the Court assessed the relevant data collected during discovery and found that there was no support for the district court’s finding that Watson would sell any infringing commercial products.

This pair of opinions clarifies a patentee’s burden of proving infringement in ANDA cases. First, although the filing of an ANDA without more does not establish infringement apart from permitting jurisdiction under § 271(e), an ANDA specification answers the infringement question when the product described either comprises all limitations of an asserted claim or is outside the scope of asserted claims. Where an ANDA is silent on particular claim limitations, the patentee must prove that the finished, commercial ANDA product—the product that is “likely to be sold”—will infringe.