Tag: AB and B codes

Therapeutic Equivalence Codes: How the FDA Determines Which Generics Can Be Substituted

Therapeutic Equivalence Codes: How the FDA Determines Which Generics Can Be Substituted
4 January 2026 Shaun Franks

Learn how the FDA uses therapeutic equivalence codes to determine which generic drugs can be safely substituted for brand-name medications. Understand A and B ratings, why some generics aren't interchangeable, and how this system saves billions in healthcare costs.