30-Month Stay: How Patent Litigation Delays Generic Drug Approval

When a brand-name drug hits the market, it usually has a patent that gives the company exclusive rights to sell it for about 20 years. But that clock doesn’t start ticking from the day the patent is filed-it starts when the drug gets FDA approval. By the time a drug reaches patients, the patent might already have five or six years eaten up by clinical trials and regulatory review. That’s why Congress passed the Hatch-Waxman Act in 1984. It was meant to strike a balance: let generic drugmakers enter the market faster, but give brand companies enough time to protect their investment. One of its most powerful tools? The 30-month stay.

What Exactly Is the 30-Month Stay?

The 30-month stay is a legal pause on FDA approval for a generic drug. It kicks in when a generic company files what’s called a Paragraph IV certification. That’s their way of saying, "We think your patent is invalid or we don’t infringe it." If the brand-name company sues within 45 days, the FDA can’t approve the generic for up to 30 months-even if the generic’s drug is scientifically perfect and ready to go.

This isn’t a court ruling. It’s an automatic administrative hold. The FDA doesn’t decide if the patent is valid. It just hits pause. The clock starts the day the last patent holder gets notice of the Paragraph IV filing. And here’s the catch: the FDA can still review the application during this time. They can even give tentative approval. That means the generic is cleared on paper, but they can’t sell it until the stay ends.

In 2022, the FDA gave tentative approval to 78% of ANDAs still under patent litigation. That’s 816 applications sitting in limbo, ready to launch the moment the legal fog clears.

Why Does This Delay Generic Drugs?

At first glance, 30 months sounds like a fair buffer. But in practice, it’s often just the beginning of the delay.

The median time between a brand drug’s approval and a generic challenge? About 5.2 years. The median time between the end of the 30-month stay and when the generic actually hits shelves? A full 3.2 years. That’s over three years after the legal barrier is gone-and still no generic in sight.

Why? Because the real delay isn’t the 30 months. It’s what happens before and after.

Brand companies often file multiple patents on minor changes: a new pill coating, a different dosage form, a new method of use. Even though the 2003 Medicare law stopped them from getting multiple 30-month stays for the same generic applicant, they still file new patents as old ones expire. Each one can restart the clock-or at least delay the launch through legal noise.

A 2019 Brookings study found that 67% of patents listed for top-selling drugs were filed after the original drug approval. These aren’t breakthrough innovations. They’re tweaks. But under current rules, they still trigger stays.

And then there’s the settlement problem. In 2017, the FTC found that 78% of patent lawsuits between brand and generic companies ended in settlements. Many of these settlements included deals where the generic company agreed to delay launch in exchange for cash or other perks. These are called "pay-for-delay" agreements-and they’re legal, even though they keep prices high.

Who Benefits? Who Loses?

The brand companies argue the 30-month stay is essential. Without it, they say, no one would invest in new drugs. Scott Gottlieb, former FDA commissioner, points out that since 1984, over 12,000 generics have been approved, saving consumers $2.2 trillion. That’s real money.

But the cost of delay is staggering. The FTC estimates that patent litigation delays, including the 30-month stay and pay-for-delay deals, add $13.9 billion to U.S. drug costs every year. For patients on expensive medications like insulin or cancer drugs, that delay can mean thousands in out-of-pocket costs.

Generic manufacturers aren’t sitting idle. They spend $3-5 million per ANDA just on legal fees. And they start preparing for litigation years before the patent expires. One Teva regulatory specialist noted on a pharma forum that the 30-month stay often gives brand companies a false sense of security. The real bottleneck isn’t the law-it’s their own internal delays. The generic is ready. The FDA says go. But the brand company’s commercial team isn’t prepared to compete on price.

How Does This Compare to Other Countries?

The U.S. is an outlier. In the European Union, there’s no patent-linked stay at all. Generic companies can file for approval as soon as the patent expires. Canada has a 24-month stay, but it’s shorter and less frequently triggered. The U.S. system is the only one that ties regulatory approval directly to patent litigation outcomes.

That makes the U.S. unique-but not necessarily better. In 2022, the FDA approved only 782 final ANDAs out of 1,046 submitted. The rest were blocked by patent or exclusivity issues. That’s a 25% rejection rate not because the drugs were unsafe or ineffective, but because of legal delays.

What’s Changing? The Push for Reform

There’s growing pressure to fix this. The FDA’s 2023 draft guidance wants stricter rules on what patents can be listed in the Orange Book. No more listing patents on packaging or unused methods of use.

Congress is also stepping in. The Affordable Prescriptions for Patients Act, introduced in early 2023, proposes cutting the 30-month stay to 18 months and banning stays for secondary patents. The FTC has called the current system a "patent thicket"-a web of overlapping patents designed to block competition.

If these reforms pass, over $78 billion in branded drugs set to lose patent protection by 2028 could see generics arrive faster. That could save consumers $195 billion, according to Evaluate Pharma.

But the drug industry isn’t backing down. PhRMA warns that shortening the stay could cut R&D investment by $14 billion a year and delay dozens of new drugs. They argue the system works-it’s just being misused.

What Does This Mean for Patients?

If you’re waiting for a cheaper version of your medication, the 30-month stay is likely the reason it’s not on the shelf yet. Even after the patent expires, you might wait years. The FDA approves the drug. The generic maker is ready. But the courts, the settlements, the patent games-they’re still in the way.

The system was designed to balance innovation and access. But today, it often feels like a delay machine. The 30-month stay isn’t the villain. It’s the tool. And like any tool, it’s only as good as the hands that use it.

What Happens After the Stay Ends?

Once the 30-month clock runs out-or if the court rules in favor of the generic-the FDA lifts the hold. But that doesn’t mean the drug immediately hits pharmacies.

The first company to file a successful Paragraph IV application gets 180 days of exclusive marketing rights. That’s a huge incentive. So if two companies challenge the same patent, they race to file first. In 2022, 72% of drugs faced multiple Paragraph IV challenges-up from 58% in 2018.

The winner gets a head start. The others wait. And sometimes, the winner doesn’t launch right away either. They wait for the right pricing window. Or they negotiate with the brand company. The market is complicated.

Can You Track This?

Yes. The FDA’s Orange Book lists all patents linked to brand drugs. It’s public. Generic companies use it to plan their challenges. Patients and advocates can use it too. If your drug has 8 patents listed, that’s a red flag. It doesn’t mean the drug is better-it means someone’s trying to keep generics out.

The FDA also publishes monthly data on ANDA submissions and approvals. Tentative approvals are tracked separately. If a drug has been tentatively approved for over a year, it’s likely stuck in litigation or a settlement.

Bottom Line

The 30-month stay was never meant to be a 5-year delay. It was meant to be a bridge-giving brand companies time to defend their patents without blocking generics indefinitely. Today, it’s often a roadblock.

The real issue isn’t the law. It’s how it’s used. Patent thickets. Pay-for-delay deals. Strategic litigation. These aren’t bugs in the system. They’re features.

Patients pay the price. So do taxpayers. So does the U.S. healthcare system.

Reform is coming. Whether it’s enough to fix the imbalance? That’s the next chapter.