FDA Orange Book: Where to Find Patent Expiration Dates for Generic Drugs

The FDA Orange Book is the single most important tool for anyone trying to figure out when a brand-name drug will lose its patent protection and allow generics to hit the market. If you're a pharmacist, a generic drug manufacturer, a patient waiting for a cheaper version of your medication, or even a researcher tracking drug pricing trends, knowing where to find accurate patent expiration dates can save time, money, and even lives.

What Is the FDA Orange Book?

The FDA Orange Book, officially called Approved Drug Products with Therapeutic Equivalence Evaluations, isn’t just a dusty reference book anymore. It’s a live, daily-updated database that lists every approved small-molecule drug in the U.S. and the patents tied to them. Created under the Hatch-Waxman Act in 1984, it was designed to balance innovation with access - giving brand-name companies time to recoup R&D costs while setting clear rules for when generics can enter.

It doesn’t just list patents. It also tracks regulatory exclusivities - extra protections that aren’t patents but still block generics. These can include data exclusivity, orphan drug exclusivity, or pediatric exclusivity. The key is this: a drug can have patents, exclusivity, both, or neither. And they don’t always expire at the same time.

Where to Find Patent Expiration Dates

The easiest way to find patent expiration dates is through the Electronic Orange Book on the FDA’s website. Here’s how to do it step by step:

1. Go to the Electronic Orange Book.
2. Search by the drug’s brand name (like Brilinta), active ingredient (like ticagrelor), or application number.
3. Click on the application number (e.g., NDA 022154) for the drug you’re looking up.
4. Scroll to the bottom of the page and click View next to "Patents and Exclusivity."
5. You’ll see a list of all patents listed for that drug, each with a patent number, expiration date, and a "Use Code" (like U-123).

For example, if you look up Brilinta (ticagrelor), you’ll see multiple patent expiration dates - some from 2018, others as late as 2021. That’s because different patents cover different things: the active ingredient, the pill formulation, or how it’s used to treat heart conditions.

What the Patent Expiration Date Really Means

The date you see in the Orange Book isn’t just the original patent expiry. It’s the date after any Patent Term Extension (PTE) has been added. PTEs are granted by the USPTO to make up for time lost during FDA review. If a drug took five years to get approved, the patent might be extended by five years.

But here’s the catch: the FDA doesn’t update the Orange Book if a patent expires early because the owner didn’t pay maintenance fees. A 2023 study from the National Bureau of Economic Research found that 46% of patents listed in the Orange Book expire early - and the FDA doesn’t remove them retroactively. That means the date you see might be outdated.

That’s why savvy generic manufacturers cross-check with the USPTO Patent Center. The Orange Book is a great starting point, but it’s not gospel.

Pediatric Exclusivity: The Hidden Extension

If a drug maker runs pediatric studies requested by the FDA, they get an extra six months of market protection. This doesn’t create a new patent. Instead, it’s tacked onto existing patents and exclusivities.

In the Orange Book, you’ll see the same patent listed twice:

• Once with the original expiration date
• Once with the same patent number but a date six months later

This trips up a lot of people. They think there are two patents when there’s really just one - with an extra six months of protection. If you’re trying to predict when a generic will launch, you need to look at the later date.

Patent Use Codes: What They Actually Tell You

Each patent in the Orange Book has a Use Code - a string like U-123. These codes describe what the patent covers: the drug’s use for treating high blood pressure, or its method of delivery, or how it’s combined with another drug.

Here’s the key: a patent might cover a use that’s no longer the main one. For example, a drug might originally have been approved for heart failure, but now it’s mostly used for preventing strokes. If the patent only covers the old use, a generic company might be able to launch a version that only markets the new use - without infringing.

The FDA has a Patent Use Code search tool to decode these. But it’s clunky. Many users report it doesn’t load properly. If you’re serious about this, keep a printed list of common codes handy.

Download the Data for Bulk Analysis

If you’re tracking dozens of drugs or building a market forecast, the web interface won’t cut it. The FDA provides daily downloadable data files at Orange Book Data Files.

The CSV files include columns like:

• Product No - the unique identifier for each drug product
• Patent No - the actual U.S. patent number
• Patent Expiration - in MM/DD/YYYY format
• Drug Substance Flag - "Y" means the patent covers the active ingredient
• Drug Product Flag - "Y" means the patent covers the pill, capsule, or formulation
• Patent Use Code
• Delist Requested Flag - "Y" means the patent owner asked to remove it

Companies like CVS Health and Express Scripts use these files to predict which drugs will go generic next quarter. If you’re in pharma, finance, or policy, this is the gold standard.

Red Flags to Watch For

Not everything in the Orange Book is reliable. Here’s what to watch for:

• Delist Requested = Y - If a patent owner asks to remove a patent, it often means they’ve lost the patent in court, or they no longer believe it’s enforceable. This can be a signal that a generic launch is coming soon.
• Multiple patents with close expiration dates - This is common with "evergreening," where companies file new patents on minor changes to delay generics. But if one patent expires and others are still active, the drug may still be protected.
• No patent listed at all - Some drugs have no patents. That doesn’t mean generics can’t come - it just means they’ve always been allowed to.

Why This Matters Right Now

In 2025, an estimated 78% of brand-name drug revenue will face generic competition. That’s up from 65% just five years ago. As more drugs lose patent protection, the Orange Book becomes more critical than ever.

For patients, it means cheaper drugs are coming. For insurers, it means lower costs. For generic makers, it’s a race to file. And for the FDA, it’s a balancing act - ensuring patents are respected but not abused.

Remember: the Orange Book doesn’t tell you when a generic will launch. It tells you when the legal barriers fall. The actual launch depends on whether a generic company files a Paragraph IV certification, wins a lawsuit, or waits for exclusivity to expire.

What to Do Next

If you’re looking for patent expiration dates:

1. Start with the Electronic Orange Book for quick checks.
2. For serious research, download the daily data files.
3. Always cross-check with USPTO Patent Center for early expirations.
4. Look for "Delist Requested = Y" - it’s a strong hint a patent is dead.
5. Don’t ignore exclusivity dates - they can block generics even if patents have expired.

The system isn’t perfect. But if you know how to read it, the Orange Book gives you a clear window into the future of drug pricing - and who gets to sell what, and when.