Orange Book: What it is and how it works

Definition and purpose

The Orange Book is the U.S. Food and Drug Administration’s (FDA) publicly accessible list of drug products approved as safe and effective. Its formal title is Approved Drug Products with Therapeutic Equivalence Evaluations. The list helps identify approved brand-name drugs, their active ingredients, and whether generic equivalents are available.

How a drug gets on the Orange Book

• A drug is added after successful clinical development, including Phase 3 trials, demonstrating safety and efficacy.
• The FDA evaluates the application and, if approved, lists the product in the Orange Book along with related regulatory information.

What the Orange Book contains

• Approved drug names and formulations (dosage forms and strengths).
• Active ingredients (used to find generic equivalents).
• Therapeutic equivalence evaluations that indicate whether a generic can be substituted for a brand.
• Patent and exclusivity information tied to the approved product.
• Notes about discontinued products or regulatory actions.

Using the Orange Book

• Search by active ingredient, brand name, or dosage form to find approved uses and available generics.
• Example: Searching for fluoxetine hydrochloride (the active ingredient in Prozac) shows available formulations, strengths, discontinued forms, and whether generic versions exist.
• Generic manufacturers seeking to market a product file an Abbreviated New Drug Application (ANDA) and must demonstrate bioequivalence to the reference listed drug. Approved ANDAs result in listing of the generic in the Orange Book.

Patents and exclusivity

The Orange Book records patents and regulatory exclusivities that can delay generic entry. Common types and typical durations include:
– New chemical entity exclusivity: 5 years
– New clinical investigation exclusivity: 3 years
– Orphan drug exclusivity: 7 years
– Pediatric exclusivity: additional 6 months on top of existing patents/exclusivity
– 180-day exclusivity provisions for certain Abbreviated New Drug Applications (ANDAs) such as Patent Challenge or Competitive Generic Therapy

Patent terms themselves are generally 20 years from the U.S. filing date, though various factors can extend or shorten effective market exclusivity. The Hatch-Waxman framework governs many generic entry and patent-certification processes.

Access and updates

• The Orange Book is freely available online and is the most current source for approvals and patent/exclusivity changes (the electronic version is updated frequently).
• It is also available in PDF and print, though electronic listings reflect daily updates.

Key takeaways

• The Orange Book lists FDA-approved drugs that have been shown to be both safe and effective.
• It is a primary resource for finding generic equivalents, patent and exclusivity status, and therapeutic equivalence information.
• Generic approval typically requires an ANDA demonstrating bioequivalence to the reference product; patent and exclusivity listings in the Orange Book can affect timing of market entry.