Evan P.Tassis


Washington + 1.202.879.3440

Evan Tassis, Pharm.D., is a registered patent attorney who handles patent prosecution and litigation. Evan's prosecution and litigation experience spans a wide range of industries and technologies including pharmaceuticals, medical devices, health care, fintech, and automotive. Evan practices before federal district courts and the U.S. International Trade Commission (ITC). He also conducts IP portfolio due diligence evaluations and provides regulatory and due diligence support in pharmaceutical and life sciences transactions.

Prior to joining Jones Day, Evan obtained his Doctor of Pharmacy from the University of Maryland School of Pharmacy. He also worked as a systems engineer at Agilent Technologies where he focused on high-performance liquid chromatography and mass spectrometry analytical instruments.

Evan maintains an active pro bono practice, including representing clients seeking asylum and tenants in landlord-tenant disputes.


  • Royalty Pharma and PureTech Health enter into KarXT royalty agreementJones Day advised Royalty Pharma in the acquisition of an interest in PureTech’s royalty in Karuna Therapeutics’ KarXT for up to $500 million, with $100 million in cash up front and up to $400 million in additional payments contingent on the achievement of certain regulatory and commercial milestones.