IP Law Daily, PATENT—Fed. Cir.: Preliminary injunction reversed in alopecia treatment patent dispute, (May 8, 2025)

By Kevin M. Finson, J.D.

A preliminary injunction barring a launch of a new drug was reversed because the trial court erred in finding that the injunction was necessary to prevent irreparable harm.

A pharmaceutical company was not entitled to a preliminary injunction against a competitor about to launch a drug that allegedly infringed the company’s patent, the U.S. Court of Appeals for the Federal Circuit has held. The company was unable to show that irreparable harm would arise absent the injunction because even under the best case scenario, it would not be able to launch its own product until years after the patent was to expire (Incyte Corp. v. Sun Pharmaceutical Industries, Ltd., No. 25-1162 (Fed. Cir. May 7, 2025)).

Incyte Corporation and Incyte Holding Corporation (collectively, Incyte) were the owners of U.S. Patent No. 9,662,335 (the ’335 patent), which claimed “deuterated versions of ruxolitinib, a Janus kinase (JAK) modulator used to treat diseases associated with autoimmune disorders.” Sun Pharmaceutical Industries, Ltd. and Syn Pharmaceutical Industries, Inc. (collectively, Sun) sought and obtained FDA approval for their own deuterated ruxolitinib product, which they called Leqselvi, to treat alopecia areata and intended to launch the product in October of 2024. Incyte sued for infringement in the federal district court in New Jersey and the court granted a preliminary injunction barring Sun from beginning to sell its product. Sun appealed, arguing that the trial court erred in its analysis of the likelihood of success on the merits and irreparable harm injunction factors.

Irreparable harm. The trial court had found that allowing Sun to launch the Leqselvi product would give Sun an unjust head start entering the market, specifically finding that absent an injunction Sun would be first to market, and that Sun obtaining a head start over Incyte’s product, which was still in development, would cause irreparable harm.

The Federal Circuit, however, determined that this holding was clear error because it was undisputed that Incyte’s product would not be ready to come to market until several years after the ’335 patent was to expire. Because Sun could not be enjoined from launching its product past the expiration date of the ’335 patent, it was inevitable that Sun would be first to market and have a multi-year head start, regardless of whether or not an injunction was issued. Under those circumstances, there was no non-speculative basis for the trial court to find that, absent an injunction, Incyte would suffer irreparable harm.

Because the appellate court found clear error in the trial court’s irreparable harm analysis, it reversed the preliminary injunction without reaching the parties’ arguments on the likelihood of success on the merits.

The Case is No. 25-1162.

Judge: Moore, K.

Attorneys: Mark J. Feldstein (Finnegan, Henderson, Farabow, Garrett & Dunner, LLP) for Incyte Corp. and Incyte Holding Corp. Josh Krevitt (Dunn & Crutcher LLP) for Sun Pharmaceutical Industries, Ltd. and Sun Pharmaceutical Industries, Inc.

Companies: Incyte Corp.; Incyte Holding Corp.; Sun Pharmaceutical Industries, Ltd.; Sun Pharmaceutical Industries, Inc.

Cases: Patent FedCirNews NewJerseyNews