Evergreening: How Pharmaceutical Brands Stretch Patents to Block Generic Drugs

Every year, dozens of blockbuster drugs lose patent protection. Patients expect prices to drop. Generic versions flood the market. But in many cases, they don’t. Why? Because companies have spent years preparing for this moment-not by inventing new medicines, but by evergreening.

What Evergreening Really Means

Evergreening isn’t a new drug. It’s not even real innovation. It’s a legal trick. When a drug’s 20-year patent is about to expire, companies file for new patents on tiny changes-like switching from a pill to a capsule, changing the dose, or adding a new coating. These aren’t improvements that help patients. They’re legal loopholes designed to delay generics.

The strategy exploded after the 1984 Hatch-Waxman Act in the U.S. That law let generic companies enter the market faster-but it also gave brand-name drugmakers new ways to extend their monopoly. Instead of competing on price or effectiveness, companies compete on paperwork. AstraZeneca, for example, piled up patent protections on six drugs, extending their market control by over 90 years total. One of those drugs, Nexium, was just a slightly modified version of Prilosec. The active ingredient? The same. The price? More than double.

How It Works: The Five Common Tactics

Evergreening isn’t one trick. It’s a toolkit. Here’s how it plays out in real life:

• New formulations: Changing how the drug is delivered-like switching from a tablet to a liquid or a slow-release version. No better results, just a new patent.
• Combination drugs: Mixing two old drugs into one pill and patenting the combo. Even if each ingredient was off-patent years ago.
• Method-of-use patents: Claiming a new use for an old drug. For example, patenting a heart medication for weight loss, even if the original use was for high blood pressure.
• Pediatric exclusivity: Running small studies on children to earn six extra months of protection. Often, the drug isn’t even meant for kids.
• Product hopping: Pulling the old version off the market and pushing patients to the new, patented version. Patients can’t switch back. Pharmacists can’t substitute generics. The old drug disappears, and the new one stays protected.

AbbVie’s Humira is the most extreme case. Over 247 patents were filed on one drug. That’s not innovation-that’s a patent thicket. Each patent is a fence. Together, they form a wall. Generic makers can’t afford to challenge them all. So Humira stayed price-controlled for nearly two decades, earning about $40 million a day at its peak.

Why This Costs Patients Billions

When generics arrive, prices drop by 80 to 85% within the first year. That’s the rule. But evergreening blocks that drop. The result? Millions of Americans pay hundreds or even thousands of dollars a month for drugs that could cost $20.

Diabetes, GERD, autoimmune diseases-these aren’t rare conditions. They affect tens of millions. And when companies use evergreening to protect drugs for these conditions, they’re not just protecting profits. They’re blocking access.

A 2023 study found that 78% of new patents on prescription drugs were for existing drugs, not new ones. That means the system is being used to protect old products, not reward new science. The cost? U.S. healthcare spends over $1.4 trillion a year on prescription drugs. A huge chunk of that goes to drugs kept artificially expensive by evergreening.

The Financial Math: R&D vs. Patent Games

Developing a truly new drug takes 10 to 15 years and costs about $2.6 billion. That’s real science. Real risk.

Evergreening? A few million dollars. A small clinical trial. A patent lawyer. Done in 18 months. No new molecules. No new science. Just legal tweaks.

The return on investment? Sky-high. Humira made $20 billion in sales in a single year. AstraZeneca’s Nexium brought in $5 billion annually at its peak. Those numbers don’t come from better outcomes. They come from keeping generics out.

Companies argue they need these extensions to fund future research. But the data says otherwise. The money spent on evergreening far exceeds what’s spent on actual discovery. Harvard researchers found that companies use evergreening not to fund innovation, but to replace it.

Who’s Fighting Back?

Regulators are starting to push back. The U.S. Federal Trade Commission sued AbbVie in 2022 over Humira’s patent strategy, calling it anticompetitive. The Inflation Reduction Act of 2022 gave Medicare the power to negotiate prices for the most expensive drugs-something that directly undermines evergreening’s financial model.

The European Medicines Agency now requires companies to prove a “significant clinical benefit” before granting extra exclusivity. That’s a big deal. It means you can’t just tweak a pill and call it new.

In India and Brazil, courts have rejected evergreening claims outright. They see it for what it is: a way to abuse the patent system. The World Health Organization has called it a barrier to global health equity.

What’s Next? The Future of Evergreening

Companies aren’t giving up. They’re just getting smarter.

Now, they’re moving into biologics-complex drugs made from living cells. These are harder to copy. Even if a patent expires, making a true generic version takes years and millions more. That’s the new frontier.

Some are using pharmacogenomics-patenting genetic tests that predict who responds to a drug. If you need a test to use the drug, and the test is patented, you can’t use generics without paying extra.

Others are launching “authorized generics”-their own generic version sold under a different label. It looks like competition, but it’s still the same company. It keeps prices high and confuses patients and pharmacies.

What Patients Can Do

You can’t stop evergreening alone. But you can fight back:

• Ask your doctor if a generic version exists-even if your prescription says the brand name.
• Check GoodRx or other price comparison tools. Sometimes the brand is cheaper than you think.
• Join patient advocacy groups. Pressure on lawmakers matters.
• Ask your insurer why they’re covering the brand instead of the generic. Demand transparency.

Every time you choose a generic, you’re voting against evergreening. Every time you question a high price, you’re pushing the system to change.

Why This Matters Beyond the Pharmacy

Evergreening isn’t just about pills. It’s about trust. It’s about whether the patent system serves innovation-or just profit. When companies spend more on lawyers than on scientists, the whole system loses credibility.

Patients shouldn’t have to choose between paying rent and buying medicine. Doctors shouldn’t have to explain why a $20 generic isn’t available. And the law shouldn’t reward the same drug 247 times.

The patent system was meant to encourage innovation-not to create endless monopolies. Evergreening breaks that promise. And it’s time we called it out.