Mylan Institutional LLC v. Aurobindo Pharma Ltd.

Case Name: Mylan Institutional LLC v. Aurobindo Pharma Ltd., 2017-1645, 2017 U.S. App. LEXIS 8792 (Fed. Cir. May 19, 2017) (Circuit Judges Lourie, Moore, and Reyna presiding; Opinion by Lourie, J.) (appeal from E.D. Tex., Schroeder, J.)

Drug Product and Patent(s)-in-Suit: Isosulfan Blue (triarylmethane dye); U.S. Patents Nos. 7,622,992 (“the ’992 patent”), 8,969,616 (“the ’616 patent”), and 9,353,050 (“the ’050 patent”)

Nature of the Case and Issue(s) Presented: Mylan licensed the patents-in-suit from its co-plaintiff, Apicore US LLC. The patents-in-suit generally related to Isosulfan Blue (“ISB”), a triarylmethane dye used to map a patient’s lymph nodes. The ’992 and ’616 patents were process patents that taught the preparation of ISB by treating isoleuco acid with silver oxide. The ’992 patent contained the additional limitation that 2.0-3.0 equivalents of silver oxide be used in the reaction. The ’050 patent also related to ISB, but instead of teaching a process, the ’050 patent claimed ISB with a purity greater than 99.0% as measured by high performance liquid chromatography (“HPLC”). At the time, other formulations of ISB existed on the market, but were of limited use due to impurity problems and were eventually withdrawn from the market.

Aurobindo sought FDA approval to manufacture and market a generic ISB product, using manganese dioxide, instead of silver oxide, as a reagent. Aurobindo solved the purity problem by using preparatory HPLC to achieve an ISB product with 99.5% purity. Mylan sued Aurobindo for infringement and sought a preliminary injunction against Aurobindo, which the district court granted with respect to all three patents. On appeal, the Federal Circuit reversed with respect to the ’992 and ’616 patents, but affirmed the preliminary injunction for the ’050 patent.

Why Plaintiffs Prevailed: With regards to the ’992 and ’616 patents, Aurobindo only appealed the district court’s determination that it more likely than not infringed the patents. The district court premised its determination on the “function, way, result” test, concluding that Aurobindo’s process was equivalent to the process described in those patents.

The Federal Circuit held that the district court improperly applied the “function, way, result” test. In particular the court found that the district court conflated the “function” and “way” prongs of the test and, in so doing, failed to address adequately the “way” prong. In its analysis, the district court correctly concluded that the function of the silver oxide and the manganese dioxide were the same, namely, oxidizing the precursor compound to form ISB. That, however, did not address the “way” these reagents accomplished this function. Because Aurobindo argued that the two reagents oxidized in different ways, there was sufficient doubt to defeat the preliminary injunction with regards to the process patents.

There was no similar error in the district court’s analysis of the ’050 patent. Here, Aurobindo appealed the lower court’s determination that: (i) it failed to raise a substantial question concerning the validity of the ’050 patent; and (ii) absent an injunction, Mylan would suffer irreparable harm. The Federal Circuit found no error in the district court’s reasoning on either point.

To support its invalidity argument, Aurobindo relied on the fact that ISB was known in the art at the time of invention. While this was true, pure ISB was not known in the art. Because the ’050 patent required pure ISB, it was inventive over the prior art. Further, the claims of the patent were not indefinite, because the phrase “by HPLC” was understood by a person of ordinary skill as a common, relied-upon technique in the scientific community. Thus, Aurobindo failed to raise a substantial question as to the validity of the ’050 patent.

The Federal Circuit also agreed with the district court’s conclusion that Mylan would be irreparably harmed without an injunction. Aurobindo’s infringement caused and would continue to cause lost sales, price erosion, lost research and development costs, and force Aurobindo to directly compete with an infringer. Further, the harm was causally linked to the infringement because, Aurobindo could not market its product unless it were to receive FDA approval for a product that likely infringed the ’050 patent. Finally, without infringing the patents in suit, Aurobindo would not be able to make its ISB product. These factual determinations supported the preliminary injunction, and the Federal Circuit agreed.