Case Name: Ferring B.V. v. Watson Labs., Inc.—Florida I, No. 2014-1377 (Fed. Cir. Aug. 22, 2014) (Circuit Judges Lourie, Dyk, and Reyna presiding; Opinion by Dyk, J.) (Appeal from D. Nev., Jones, J.)

Drug Product and Patent(s)-in-Suit: Lysteda® (tranexamic acid); U.S. Patents Nos. 7,947,739 (“the ’739 patent”), 8,022,106 (“the ’106 patent”), and 8,273,795 (“the ’795 patent”)

Nature of the Case and Issue(s) Presented: The issue of infringement in this case relates entirely to dissolution rates. Apotex sought to market its generic product by designing around Ferring’s Lysteda. In its 2010 ANDA, Apotex only included one dissolution specification: that at least 80 percent by weight of the active ingredient would dissolve in 60 minutes. Apotex then certified pursuant to paragraph IV that it did not infringe any of the patents-in-suit. Ferring then filed suit. The patents-in-suit claimed dissolution rates of < 70% in 45 minutes, > 50% in 90 minutes, or 100% in 120 minutes.

The district court construed the term “about” as it pertained to the amount of tranexamic acid released at specified times, i.e., “less than about 70% by weight…at about 45 minutes,” to mean “approximately” and declined to give that term any numerical value. At trial, Ferring conceded that Apotex’ actual generic product, based on its dissolution sample data, did not infringe the patents-in-suit. However, the district court, analyzing only Apotex’ 2010 ANDA, concluded that because the 2010 ANDA was silent with respect to weight percent of tranexamic acid released at the times specified in the patents-in-suit, the ANDA permitted Apotex to sell an infringing product. Thus, Apotex agreed to amend its ANDA specification to include a restriction that “not less than 75% by weight of the tranexamic acid was released at 45 minutes.” Apotex also agreed that it inform Ferring and the district court if it ever attempted to change the dissolution specification in the future. Ferring appealed the district court’s non-infringement decision concerning the 2010 ANDA and its decision that Ferring’s complaint alleging infringement of the patents-in-suit by the amended 2014 ANDA was mooted. The Federal Circuit affirmed.

Why Apotex Prevailed: The district court erred when it relied on the “not less than 80%...of the labeled amount of tranexamic acid dissolved in 60 minutes” language from the 2010 ANDA as the basis for finding that Apotex “could” violate the patents-in-suit. The 2010 ANDA does not “clearly describe a product that meets the limitations of the asserted claims.” Rather, the 2010 ANDA is silent with respect to the claim limitations of the patents-in-suit, which do not specify dissolved dissolution rates at 60 minutes. When the ANDA is silent with respect to infringement, the correct analysis focuses on the product that is likely to be sold, or, more preferably, what will be sold. Here, Apotex provided bio-batch data that shows what it is likely to sell, and Ferring’s expert testified that none of the tablets was infringing. Therefore, the Federal Circuit found that Apotex’s 2010 ANDA would not infringe the patents-in-suit.

Whether the 2014 ANDA infringes the patents-in-suit is dependent on the propriety of the district court’s construction of the term “about” to mean “approximately” and the court’s not affording that term any numerical value. Ferring argued that the 2014 ANDA infringes because its proposed construction of “about” to mean “+ 10% should have been adopted and under that construction, the patented range of dissolution at 45 minutes would include from 63 to 77 percent by weight dissolution. Ferring relies on the fact that the patent claim references the USP 27 Type II Paddle Method. But nothing in the USP test creates the tolerance that Ferring would have the Federal Circuit adopt. Instead, the USP provides that where a dissolution rate is measured using 900 mL volume as the patents-in-suit require, a chemist may use a volume of 810 mL or 990 mL sample for the assay. The dissolution rate calculated based on that volume must be exact. Moreover, “about” is not defined either explicitly or implicitly in the patents-in-suit. The Federal Circuit found that the district court did not err in finding that the term “about” meant “approximately.” Therefore, the 2014 ANDA speaks directly to the question of infringement and would not permit Apotex to market an infringing product.

Finally, as a matter of policy, the Federal Circuit found that there is no support for the proposition that the question of infringement must be addressed solely based on the initial ANDA. This is true based on statutory interpretation and precedent. A district court may reconsider its own finding of infringement in light of an amended ANDA or other information. That being said, a district court need not always consider any ANDA amendment because “[a]llowing an amendment is within the discretion of the district court, guided by principles of fairness and prejudice to the patent-holder.”