The US Food and Drug Administration (FDA) has released its 33rd edition of its so-called "Orange Book"-its listing of all approved drug products and their therapeutic equivalence evaluations.
The book is widely used in the regulatory community for identifying which drug products are substitutable for one another.
The book contains all drug products that are approved or have not been withdrawn for reasons of safety or efficacy with the exception of products marketed before 1938 (pre-Federal Food, Drug And Cosmetic Act) or products approved solely on the basis of their safety (such as those approved through FDA's Drug Efficacy Study Implementation).
The book's usefulness comes down to two main points: as a listing for therapeutic equivalence, and for patent exclusivity.
To the former, many state laws only allow generic substitution for products contained within the Orange Book and known to be therapeutically equivalent.
To that end, the book identifies products that are both therapeutically equivalent and therapeutically similar. Products that are coded as "A" (AA, AN, AO, AP, AT or AB) are known to FDA to be therapeutically equivalent, having no known or unresolved bioequivalence issues.
Products that are coded in the Orange Book as "B" (BC, BD, BE, BN, BP, BR, BS, BT, BX) are not therapeutically equivalent, and either have bioequivalence issues that are known or issues that remain unresolved (but potentially resolvable, which would allow them to be coded as AB).
To the latter point of patents, each product is also associated with the name of the holder of the application, as well as the status of the patent and market exclusivity status of the drug.
Though the list is updated on a monthly basis, the yearly editions are seen as more comprehensive and are more easily referenced than the monthly piecemeal reports.