Jason Leonard - McDermott Will & Emery


Jason Leonard advises clients on complex life sciences patent litigation. During his 14 years of practice, he has counseled numerous pharmaceutical companies in developing effective patent litigation strategies for a wide array of pharmaceutical products. He leads and directs patent litigations involving small molecule drugs and peptides, including cancer therapies, oral contraceptives, steroids, antifungal agents, anticholinergics, β3-agonists and pharmacologic stress agents. Jason has successfully defended patents covering new chemical compounds, as well as complex inventions covering formulations, polymorphs, and methods of treatment. Clients frequently rely on him to address difficult infringement issues, particularly when design-around defenses have been asserted and extensive infringement proofs must be presented at trial.

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  • Represented Astellas against nine defendants in Astellas v. Actavis relating to polymorph and method of treatment patents covering Myrbetriq® (a β3-agonist for the treatment of overactive bladder). Cases settled very favorably for Astellas*
  • Successfully represented Astellas relating to an IPR petition filed by Sawai concerning a compound patent covering Myrbetriq® (a β3-agonist for the treatment of overactive bladder). The PTAB did not institute the petition*
  • Successfully represented Sanofi in Sanofi v. Fresenius relating to a compound patent covering Jevtana® (a taxane chemotherapy agent for docetaxel-resistant prostate cancer). Sanofi prevailed at trial on the compound patent and injunction obtained*

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  • Legal 500 US, Intellectual Property: Patents: Litigation (Full Coverage), Recommended, 2020


Franklin Pierce Law Center, JD, cum laude, 2007
University of Connecticut, BS, Chemistry, cum laude, 1998

New York
New Jersey

US Supreme Court
US Court of Appeals for the Federal Circuit
US District Court for the District of New Jersey
US District Court for the Southern District of New York
US District Court for the Eastern District of New York