Researchers have identified 38 businesses engaged in direct-to-consumer marketing of purported stem cell treatments and exosome therapies for preventing and treating COVID-19 even though these “interventions” have not been approved or authorized by national regulatory bodies and are not supported by convincing safety and efficacy data.

The analysis, appearing in the journal Stem Cell Reports, also found most of these companies are claiming to treat long COVID, the persisting brain fog, fatigue, and other symptoms seen in some individuals who have had COVID-19.

“People who are going online and looking for treatments, especially for long COVID, need to be alert to marketing misrepresentations that minimize risks and make misleading claims about the likelihood of benefits,” says first author Leigh Turner, a bioethics professor in the University of California, Irvine Department of Health, Society, and Behavior.

“It’s understandable given the considerable number of individuals that continue to experience illness following the acute infection phase of COVID-19. It’s also disturbing because the people paying for these products are not being provided access to evidence-based treatments.”

In the early months of the pandemic, Turner published a similar analysis in the journal Cell Stem Cell of U.S. businesses that were marketing unlicensed and unproven stem cell-based therapies and exosome products that claimed to prevent and/or treat COVID-19. The companies found in the current study continue to make those claims, while adding claims about long COVID—36 of the 38 businesses in this analysis specifically said they had treatments for it.

“The patients being targeted by such marketing claims are particularly vulnerable,” Turner says. “They’re suffering, and in some cases, they’ve been suffering for a long time, making them highly susceptible to misleading marketing representations and persuasive marketing pitches. And while some of these patients might have access to reputable long COVID clinics working with best available evidence, that access doesn’t mean they’re getting the therapeutic relief they are seeking.”

In addition to the potential medical and psychological risks of using these products, many of them are also expensive. For the subset of businesses included in the current analysis that revealed information about pricing on their websites, the cost of “treatments” was anywhere from $2,950 to $25,000. “In addition to the possibility of being harmed by these products, there’s also the possibility of being scammed out of thousands of dollars,” Turner says.

Of the businesses found operating in spring of 2020, just one of them was still marketing interventions for COVID-19 at the time of the new study. “It’s a shape-shifting marketplace,” Turner says. “Some businesses stopped marketing after receiving warning letters from the Food and Drug Administration or the Federal Trade Commission. Other companies and clinics have entered the marketplace and in some cases apparently managed to avoid detection by regulatory bodies and law enforcement agencies.”

Of the 60 clinics operated by these businesses, 24 are based in the US, and 22 are in Mexico, with other clinics located in the Cayman Islands, Guatemala, Malaysia, Panama, Philippines, Poland, Spain, Thailand, Ukraine, and the United Arab Emirates.

“There was a robust response from regulatory bodies and law enforcement agencies to companies making unsubstantiated claims in the early days of the pandemic,” Turner says.

“I hope this study encourages regulatory bodies and law enforcement agencies in these countries to continue to act in response to these businesses, which are putting patients at risk of physical injuries and financial losses by using misleading marketing representations to sell unapproved and unproven products.”