George O'Brien is a partner in Mayer Brown's Washington DC office and a member of the Corporate & Securities practice. He works with life sciences companies of all sizes to assist them in developing and marketing innovative products that are regulated by the US Food and Drug Administration, including drugs and biologics, medical devices, drug-device combination products, CBD and botanical products, medical foods and dietary supplements.

George has deep experience providing regulatory advice to pharmaceutical and biotech companies on lifecycle management issues, including regulatory exclusivities and FDA-facing patent issues. He is a leading expert on orphan drug matters, including orphan designation and exclusivity, and has successfully advocated on behalf of clients to FDA on matters related to prevalence, orphan subsets, and clinical superiority. George also regularly advises pharmaceutical and biotechnology companies on pediatric study and pediatric exclusivity issues arising under the Best Pharmaceuticals for Children Act and the Pediatric Research Equity Act.

George has an active practice drafting citizen petitions and has obtained key victories for his clients on several issues, including bioequivalence and approval requirements for generic drug products, the operation of 180-day exclusivity, and therapeutic equivalence issues, as well as a groundbreaking petition that persuaded FDA to expand its application of new chemical entity exclusivity to fixed-dose combination drug products.

George regularly works with life sciences clients on FDA-facing patent issues. As part of this practice, he routinely assists clients on the submission of patent information to FDA’s Orange Book and Purple Book. George also works closely with his IP colleagues during the entire Hatch-Waxman litigation process to ensure that intellectual property protections and regulatory strategies are aligned throughout a product’s lifecycle.

George previously served on the Food and Drug Law Institute’s Drugs & Biologics Committee. He regularly speaks and writes on FDA life sciences issues at FDLI’s annual conference and elsewhere.


University of Maryland Francis King Carey School of Law, JD, magna cum laude
Order of the Coif

Dartmouth College, AB, cum laude

University of Pennsylvania, MA


  • District of Columbia
  • Maryland
  • Rising Stars, Food & Drugs, Washington DC Super Lawyers, 2018
  • Healthcare: Life Sciences, Recommended, Legal 500 US, 2020