Sanofi and Regeneron Before The US Court of Appeals for the Federal Circuit

Arnold & Porter Kaye Scholer LLP advised Sanofi-Aventis US and Regeneron Pharmaceuticals Inc. on the deal.

Pharmaceutical companies Sanofi-Aventis US and Regeneron Pharmaceuticals Inc. obtained a victory in one of the most closely watched biotechnology cases in recent years.          The case involved important issues relating to antibody patents and its outcome will significantly impact companies developing therapeutic antibodies.

In 2014, another biotechnology company sought billions of dollars in damages and a permanent injunction against the sale of Sanofi and Regeneron’s lifesaving and cholesterol-reducing drug Praluent over patent disputes. In 2017, the Federal Circuit reversed a jury verdict for that company and remanded for a new trial on written description and enablement, concluding that a lower court had wrongly excluded evidence and issued an erroneous jury instruction. The Federal Circuit also vacated a permanent injunction in favor of that company. Prior to the trial, the Delaware District Court dismissed claims of willfulness.

During the February 2019 re-trial, the jury found two of the five patent claims asserted were invalid, with the other three being held valid. 

On February 11, 2021, the Federal Circuit affirmed this victory.

Sanofi-Aventis U.S. LLC develops, manufactures,, and markets pharmaceutical products. The Company was founded in 1950 and is located in Bridgewater, New Jersey. Areas that Sanofi US cover include cardiovascular disease, central nervous system ailments, and metabolic disorders.

Regeneron Pharmaceuticals, Inc. is a biopharmaceutical company. The Company discovers, develops, and commercializes pharmaceutical products for the treatment of serious medical conditions. Regeneron Pharmaceuticals serves the healthcare sector in the United States.

The Arnold & Porter team included partner Matt Wolf (Picture), who co-chairs the firm’s Intellectual Property group; partners David Barr, Deborah Fishman, and Daniel Reisner; and associate Victoria Reines.



Involved fees earner: David Barr – Arnold & Porter Kaye Scholer LLP; Deborah Fishman – Arnold & Porter Kaye Scholer LLP; Victoria Reines – Arnold & Porter Kaye Scholer LLP; Daniel Reisner – Arnold & Porter Kaye Scholer LLP; Matthew Wolf – Arnold & Porter Kaye Scholer LLP;

Law Firms: Arnold & Porter Kaye Scholer LLP;

Clients: Regeneron Pharmaceuticals, Inc.; Sanofi-Aventis SA ;

Author: Martina Bellini