Four pharmaceutical companies have filed hundreds of patents to keep their drugs safe from generic competition and extend their “unprecedented profits”, according to a report released Thursday.

Overuse of the patent system – by drugmakers Bristol-Myers Squibb, AbbVie, Regeneron and Bayer – is keeping drug prices sky-high, often to the detriment of U.S. consumers, according to the report by the Initiative for Medicines, Access & Knowledge, or I-MAK, a non-profit organization that advocates pharmaceutical patent reform.

“They get the power, they get the monopoly, and they start to raise their prices,” said Priti Krishtel, a healthcare lawyer and co-founder of I-MAK.

The US patent system aims to reward innovation by allowing pharmaceutical companies to sell new drugs on the market and prohibiting other manufacturers from making generic versions for a set period of time – usually 20 years. Once the patent expires, generics are allowed on the market, often at a lower list price than the brand name drug.

But drugmakers often extend their patents by making small changes to drugs, maintaining their monopolies for several years.

Legal experts call the tactic “perpetuity,” said Stanford University law professor Mark Lemley, who was not involved in the I-MAK report.

This is an approach seen throughout the pharmaceutical industry: Pharmaceutical companies file an average of more than 140 patent applications per medicine, according to the I-MAK report. Of these patent applications, 66% were filed after the Food and Drug Administration approved the drug for marketing.

These additional patents are “absolutely” to expand their monopolies, said Arthur Caplan, chief of the medical ethics division at NYU Langone Medical Center.

While the practice of evergreening is not necessarily illegal, said Caplan, who also did not participate in the report, it is unethical. “It is clear that the system is manipulated and we need to rethink the rules of patenting.”

Tahir Amin, intellectual property researcher and co-founder of I-MAK, put it bluntly: “Companies are playing with the system.”

For this reason, advocates say reforming the patent system is an important next step in the country’s efforts to reduce exorbitant drug prices. Last month, President Joe Biden signed into law the Cut Inflation Act, which lowers prescription drug costs for Medicare patients but leaves out millions of privately insured Americans and non- insured.

Extended patents and legal battles

The new report highlighted patenting practices on a handful of blockbuster drugs.

Revlimid, a multiple myeloma drug made by New York-based Bristol-Myers Squibb, generated $8.7 billion in annual sales in 2021, which is 30% of the company’s overall revenue, according to The report. The original patent on the drug expired in 2019, but the drugmaker won’t face competition until 2026.

At least 206 patents have been filed on the drug, which Bristol-Myers acquired through its acquisition of drugmaker Celgene in 2019. Nearly three-quarters of those patents were sought after its FDA approval in 2005, according to the report.

Humira, a rheumatoid arthritis drug from Chicago-based biotech company AbbVie, generated $17.3 billion in annual sales in 2021. There are 311 patent applications for the drug, 94% of which were filed after the FDA approval. AbbVie’s original patent on the drug expired in 2016, but it won’t face competition until 2023.

Eylea, a drug for vision problems including age-related macular degeneration from Regeneron and Bayer, has 134 patent applications, 65% of which were filed after the drug was approved in 2011. It generated 5 $.8 billion in annual sales last year. Its exclusivity is set to expire in 2023, but it is unlikely to face competition soon, according to I-MAK. Indeed, some of his additional patents on the drug do not expire until 2040.

Bristol-Myers Squibb, AbbVie, Regeneron and Bayer did not respond to requests for comment.

The practice of patent extension is not always unchallenged. In some cases, generic manufacturers are suing drugmakers to get their drugs to market, Lemley said. However, he added, these lawsuits often end in settlements between the companies.

On Monday, Gilead Sciences announced a settlement with five generic drugmakers over its anti-HIV drugs Descovy and Odefsey, as well as the hepatitis B drug Vemlidy. Both HIV drugs had faced generic competition as early as 2025, but the settlement delayed the arrival of generics until 2031.

Settling the lawsuit is “essentially paying for the credits to go away,” Lemley said.

The regulations are anti-competitive, Caplan said, because drugmakers pay to eliminate competition.

The US Patent and Trademark Office (PTO), which grants patents to drugmakers, said it is working to prevent drug companies from unduly delaying generic competition.

A spokesperson for the bureau did not issue an immediate statement on the report, but told NBC News of a blog post written in July by PTO Director Kathi Vidal and FDA Commissioner Dr. Caliph. He detailed how agencies are developing policies to preserve the US patent system while advancing competition that can lower drug prices.

While the patent system is important for encouraging innovation for new medicines, it “should not be used to unduly delay generic medicine and biosimilar competition beyond what is reasonably contemplated by law. “, they wrote.

In the meantime, Caplan said he expects to see more litigation from the Justice Department challenging the drug companies’ additional patents.

I-MAK’s Krishtel said the federal government should also begin to take a more critical look at patent filings and perhaps “raise the bar” for what is considered a drug improvement.

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