William focuses his practice on issues related to the approval, regulation, promotion, sale and reimbursement of drugs, medical devices, biologics, excipients, dietary supplements, foods and cannabis-related products.

William assists clients in their interactions with various federal agencies including the following:

• Food and Drug Administration (FDA)
• Centers for Medicare & Medicaid Services (CMS)
• Drug Enforcement Administration (DEA)
• Federal Trade Commission (FTC)
• Health and Human Services (HHS)

William's experience includes reviewing and revising the labeling of drugs, medical devices, foods and dietary supplements to ensure compliance with the FDA law and regulations. He works with clients to petition the FDA to ensure the safety and effectiveness of drug products on the market. He also assists in providing input to members of Congress regarding proposed legislation and highlighting arbitrary enforcement actions by federal and state agencies.

William is also co-head of the firm's cannabis group, where he assists companies in navigating federal and state law issues related to the promotion and sale of cannabis-related products. William has helped companies work to bring FDA-approved cannabinoid drug products to market as well as helped clients navigate the sale of cannabis and hemp-related products.

Since 2013, William has been consecutively named to the Washington, D.C. Super Lawyers Rising Stars list. He is also recognized as a Nationwide Band 1 Cannabis Lawyer by Chambers USA in 2019.