Federal Circuit IP

H. Lundbeck A/S v. Lupin Ltd.

By Samuel Thacker Published January 10, 2024

CAFC Opinion No. 2022-1194, Decided December 7, 2023

(Dyk, Prost, Hughes)


Overview: No infringement of narrow method-of-use pharma patent where generic drug is labeled for a broad/general use claimed in an expired patent.

Facts/Procedural Posture:

  • Lundbeck initially obtains patents on using drug to treat depression (the broader patents)
  • Then, after finding that the drug is less likely to cause sexual dysfunction than other antidepressants, H. Lundbeck obtains narrower patents claiming use of the drug to treat depression in patients who have weaned off another antidepressant due to sexual dysfunction side effects.
  • Lupin submits ANDAs to get FDA approval to market a generic to treat depression when the broad patents expire.
  • Lundbeck sues Lupin, seeking to enjoin them from marketing the new generic until after the narrower use patents expire (one of them does not expire until 2032).
  • Ct. finds no infringement of narrower use patents; H. Lundbeck appeals.


Issue on Appeal: Whether D. Ct. erred in finding no infringement of H. Lundbeck’s narrower use patents?

Holding & Order: D. Ct. did not err in finding no infringement; affirmed.

Fed. Cir. Analysis:

  • Nothing in Lupin’s label encourages, recommends, or promotes an infringing use, i.e., administering to patients who weaned off another antidepressant due to sexual dysfunction side effects.
  • Lupin’s label says only that its generic drug is to be used to treat depression. Lupin does not infringe just because patients who have experienced sexual dysfunction from other antidepressants happen to try Lupin’s product.
  • “A patentee may not use Hatch-Waxman to maintain its exclusivity merely by regularly filing a new patent application claiming a narrow method of use.” Decision at 14.
  • Court recognizes that the outcome would have been different if patient safety had been implicated. For example, if it had been discovered that the drug was safe only for patients covered by the narrower patents (patients who had previously experienced sexual dysfunction with other antidepressants) and Lupin were forced to put instructions on its label to administer only to these patients, then Lupin likely would have been enjoined.


  • For patent owners:
    • Unless a follow-on patent’s narrower drug use is critical to patient safety, it will be difficult to stop general uses of the drug once the original, broader use patent expires.
  • For generic drug manufacturers:
    • Be mindful that a non-infringing product today can become an infringing product in the future if label requirements change.