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

When a brand-name drug hits the market, it doesn’t just have a patent-it has a legal shield. That shield is called the 30-month stay, and it’s the single biggest roadblock standing between patients and affordable generic drugs in the U.S. This isn’t a glitch. It’s a feature of the 1984 Hatch-Waxman Act, designed to balance innovation and access. But today, it often looks more like a delay machine.

How the 30-Month Stay Actually Works

Here’s the simple version: When a generic drug maker wants to sell a cheaper version of a brand drug, they file what’s called an ANDA-a simplified application with the FDA. If they believe the brand’s patents are invalid or won’t be infringed, they file a Paragraph IV certification. That’s a legal challenge. The moment they do that, they must notify the brand company. If the brand sues within 45 days, the FDA is legally blocked from approving the generic for up to 30 months.

That’s the stay. It’s automatic. No judge needs to rule. No hearing is required. Just a lawsuit filed, and the clock starts. During those 30 months, the FDA can still review the generic application. They can even give it tentative approval. But they can’t say yes-final approval is frozen.

Here’s the twist: The 30 months isn’t always the end. If the lawsuit drags on past that point, the stay can extend. Courts can shorten it. But more often, they let it run. And in 2022, the FDA granted tentative approval to 78% of ANDAs still in litigation. That means hundreds of generics were ready to go-but stuck on hold.

Why It’s Not Just About 30 Months

Most people think the delay ends when the 30 months are up. It doesn’t. The median gap between the end of the stay and the actual launch of the generic? 3.2 years. Why?

Because the real delay isn’t legal-it’s commercial. Generic companies spend millions preparing for litigation. They need to build supply chains, negotiate with retailers, set pricing. Some wait to launch until after the first generic enters the market, hoping to piggyback on lower prices. Others delay because the brand company files a second lawsuit on a different patent-something the 2003 Medicare law tried to stop, but loopholes still exist.

Take a drug like Humira. It had over 100 patents listed in the FDA’s Orange Book. Even though only one triggered the initial 30-month stay, the brand used the system to keep generics out for over a decade. That’s not litigation-it’s strategy.

The First-Mover Advantage That Backfires

The Hatch-Waxman Act gave the first generic company to challenge a patent a 180-day exclusivity window. No one else can enter during that time. Sounds fair, right?

Not always. Sometimes, the first filer doesn’t launch at all. They settle with the brand company for cash or a deal to delay entry. That’s called a “pay-for-delay” agreement. The FTC found that 78% of Paragraph IV lawsuits ended in settlements that pushed generic entry past patent expiration. In 2021, these deals cost U.S. consumers $13.9 billion in extra drug spending.

And when multiple generics do file? The system works better. Drugs with more than one Paragraph IV challenger reach the market 8.2 months faster than those with just one. Competition forces faster launches. But the first filer still holds the keys.

How the U.S. Is Alone in the World

Nowhere else does this happen. In the EU, generics can launch as soon as data exclusivity ends-no lawsuits needed. Canada has a 24-month stay, but it’s not automatic. It requires a court order. The U.S. is the only country that lets a single lawsuit freeze FDA approval for two and a half years.

That’s why the FDA’s own data shows U.S. generic entry is slower than in Europe by an average of 18 months for the same drugs. And it’s why countries like India and China now make 63% of all ANDA submissions-they know the U.S. system is predictable, even if it’s slow.

Who Pays the Price?

The cost isn’t just financial. It’s human.

Diabetes, cholesterol, blood pressure-these are daily meds. When a generic is delayed, patients pay 10 times more. The average brand drug costs $150 a month. The generic? $15. That’s $1,620 a year saved per person. Multiply that by millions of patients, and you get $195 billion in potential savings over the next few years, according to Evaluate Pharma.

But the system isn’t broken-it’s being exploited. A 2019 Brookings study found that 67% of patents listed in the Orange Book for top-selling drugs were filed after the original approval. These are minor changes: a new coating, a different pill shape, a slightly altered dose. They’re not innovations. They’re legal tricks to reset the clock.

What’s Changing?

Pressure is building. In 2023, Congress introduced the Affordable Prescriptions for Patients Act. It proposes cutting the stay from 30 months to 18 and banning stays for secondary patents. The FTC is pushing for the same. The FDA’s new draft guidance wants brand companies to prove every patent listed in the Orange Book is truly relevant.

Generic manufacturers are spending $3-5 million per ANDA just on legal fees. One Teva executive told a forum: “We’ve seen the 30-month stay create false security. The litigation drags on, but the real delay is our own internal readiness.”

Meanwhile, brand companies argue that without the stay, they’d never invest in new drugs. Scott Gottlieb, former FDA commissioner, says the system has saved consumers $2.2 trillion since 1984. But Harvard’s Aaron Kesselheim counters: “It’s added 1.8 years of exclusivity on average for blockbuster drugs.”

The Bottom Line

The 30-month stay was never meant to be a tool for endless delay. It was meant to give innovators time to defend their patents-not to build a wall around their profits. Today, it does both. The FDA approves generics. The courts don’t always rule. And patients wait.

Reform is coming. Whether it’s faster, fairer, or just more honest, the system is under fire. And for the 90% of U.S. prescriptions filled with generics, the question isn’t whether change will happen. It’s whether it’ll happen before the next patent cliff hits.

By 2028, $78 billion worth of brand drugs will lose patent protection. If the 30-month stay stays the same, those drugs will stay expensive. If it changes, millions could finally get the meds they need-at prices they can afford.