Another Win for Generics: Hatch-Waxman Defendants May Develop Non-Infringement Defenses Beyond Their Notice Letters

Since the Supreme Court’s 2017 sea change venue decision in TC Heartland v. Kraft Food Group Brands, the Northern District of West Virginia has seen an uptick in substantive Hatch-Waxman litigation involving local pharmaceutical company, Viatris Inc. (formerly known as Mylan Pharmaceuticals). Viatris is frequently named as a defendant in Hatch-Waxman litigations, each of which is triggered by Viatris’s service of a statutorily-required notice letter stating why the patents that allegedly cover the brand name drug are invalid and/or not infringed by a proposed generic drug. Hatch-Waxman litigants have battled over the requirements for these notice letters in other courts. In Bausch Health Ireland Ltd. et al. v. Mylan Pharms. Inc., the Northern District of West Virginia has now added to that body of law, adopting a holding consistent with other courts that a generic drug company is not foreclosed from asserting additional defenses in litigation even if those defenses were not raised in the generic drug company’s notice letter. See No. 1:22CV20, 2023 WL 2726432, at *3 (N.D.W. Va. Mar. 30, 2023).

Background

In April 2021, Bausch Health Ireland Limited and Salix Pharmaceuticals, Inc. (collectively, Plaintiffs) sued Mylan in the Western District of Pennsylvania for infringement under the Hatch-Waxman Act due to Mylan’s submission of an abbreviated new drug application (ANDA) directed to a generic version of Trulance®, a gastrointestinal drug used in adults to treat certain types of bowel problems. Following motion practice over venue, the original litigation was stayed in spring 2022 pending resolution of another law suit filed by Plaintiffs against Mylan in the Northern District of West Virginia.  Between March and June 2022, Mylan also filed five petitions for inter partes review against Bausch’s patents, but only one was ultimately instituted.

Plaintiff’s Motion and the Court’s Opinion

On June 8, 2022, Plaintiffs filed a motion in West Virginia for judgment on the pleadings as to infringement. Mylan’s answer had denied all infringement allegations, but according to Plaintiffs, “judgment on the pleadings is appropriate despite Mylan’s denials because Mylan cannot deviate from the defenses asserted in its Paragraph IV notice letter, which did not include non-infringement arguments for every asserted claim of the patents-in-suit.” While Mylan’s notice letter was 97 pages long, it focused heavily on invalidity.

The Northern District of West Virginia denied Plaintiffs’ motion. The court found that “it possesses no authority to penalize any perceived deficiencies in Mylan’s Paragraph IV notice letter under the Hatch-Waxman Act” and, as a result, “it will not limit Mylan to the theories raised in therein.” As such, “Mylan may develop its non-infringement contentions in the ordinary course of this litigation.”

Implications

For generic drug companies, Bausch should be a welcome, recent addition cementing case law holding that the defenses raised in notice letters may be supplemented in litigation. Bausch reaffirms decades-old decisions from the District of Delaware and Northern District of Illinois rejecting similar challenges that sought to limit Hatch-Waxman litigations strictly to the defenses raised in notice letters.  E.g., Abbott Labs. v. Lupin Ltd., No. 09-152-LPS, 2011 WL 1897322, at *7 (D. Del. May 19, 2011); Abbott Labs., Inc. v. Apotex Inc., 725 F. Supp. 2d 724, 728 (N.D. Ill. 2010).  Notwithstanding the requirement that generic drug companies serve a notice letter explaining why the patents-at-issue are invalid or not-infringement, generic companies retain flexibility to develop those invalidity and non-infringement defenses during litigation – and add additional defenses – that may extend beyond what they put in their notice letters.