Jason A. Leonard

Jason A. Leonard


Partner, New York

Jason Leonard has experience in all aspects of intellectual property law, with a focus on complex pharmaceutical patent litigation. He has extensive experience litigating pharmaceutical patents in federal court, including appeals to the Court of Appeals for the Federal Circuit. Jason’s technical expertise includes new drug compounds, enantiomers, polymorphs, drug formulations, and methods of use. He has litigated patents covering oncology drugs, antifungal agents, and oral contraceptives. Jason has also advised clients regarding regulatory exclusivities at the U.S. Food and Drug administration, including patent term extensions, new chemical and product exclusivities, and GAIN.

Before practicing law, Jason worked for six years as a solid-state and analytical chemist at Pfizer. His work included development of analytical methods for drug formulations and synthesis of novel polymorphs and salts of pharmaceutical compounds. He also specialized in conducting investigations of complex scientific problems encountered during drug development. Mr. Leonard is a co-inventor on several solid-state pharmaceutical patents, including patents covering atorvastatin.

Case Highlight
Merck Sharp & Dohme Corp. v. Xellia Pharmaceuticals ApS et al.
D. Del. (2015)

Jason obtained infringement judgment on behalf of client Merck and against Xellia Pharmaceuticals concerning infringement of a patent covering injectable formulations of caspofungin, a potent antifungal agent used to treat systemic fungal infections.
Representative Matters
  • Merck in patent litigation involving its antifungal drug Cancidas® against Fresenius Kabi (2014-current)
  • Sanofi-Aventis in patent litigation involving its prostate cancer drug Jevtana® (2014-current)
  • Biotechnology Industry Organization (BIO) in petitioning as amicus curiae for a writ of certiorari in the U.S. Supreme Court in Baxter Int’l Inc. v. Fresenius USA, Inc. (2014)
  • Merck in patent litigation involving its antifungal drug Cancidas® against Xellia (2014-2015)
  • Warner Chilcott in patent litigation involving its oral contraceptive Loestrin24® (2012-2014)
  • Warner Chilcott in patent litigation involving its oral contraceptive LoLoestrin Fe® (2012-2014)
  • Merck in patent litigation involving its antifungal drug Cancidas® against Teva and Sandoz (2009-2012)
  • Sanofi-Aventis and Debiopharm in patent litigation involving its colorectal cancer drug Eloxatin® (2007-2010)
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