John Rodolf says it was the online sales pitch that helped persuade him to fork over $6,000 to the Lung Institute in Tampa, Fla., in August 2015. The institute's website cited both scientific research and patient testimonials as proof that its simple but cutting-edge stem cell therapy could successfully treat chronic obstructive pulmonary disease (COPD), a condition that left Rodolf struggling to breathe for most of his waking hours. His own doctor had described the condition as incurable. But, Rodolf says, the website suggested that restoring his ability to breathe could be as simple as extracting these special cells from his own blood and then delivering them back into his body through an IV.

What the institute didn't explain was that such treatments aren't supported by the balance of scientific evidence.

Doctors and scientists have made small but impressive strides in using stem cells to treat some complicated diseases. But so far, lung disorders aren't on the list. Rodolf, who says he got no benefit from the treatments, has signed on to a lawsuit alleging that the Lung Institute intentionally defrauded him and dozens of other patients. In retrospect, he says he wishes he had been more skeptical. "It was a bad call," he says. "But I couldn't breathe at the time, and when you can't breathe you'll try just about anything."

The Lung Institute declined to be interviewed for this article, but a spokeswoman said by email that the clinic had treated thousands of patients and that many of them had indeed seen an improvement in their quality of life.

More on Controversial Medical Practices

Scientists and federal regulators say that stories like Rodolf's illustrate something they are increasingly worried about. As evidence of stem cell therapy's potential grows, so does confusion over what this emerging medicine can and can't do. And with few consumer protections in place, unscrupulous doctors are exploiting that confusion for profit. Across the country, clinics like the one Rodolf went to are promoting stem cell therapies for a long list of conditions, including joint injuries, sexual dysfunction, COPD, lupus, and diabetes. These treatments are rarely covered by insurance, and they can cost thousands of dollars. None of them have been proved to work. Some have proved to be dangerous.

"There's an important difference between the stem cell treatments emerging from slow and careful study and the ones being sold for thousands of dollars without any evidence of safety or efficacy," says Orly Avitzur, M.D., Consumer Reports' medical director. "But that difference is not being made clear to consumers." (Read more about how to protect yourself when considering stem cell therapy.)

A Medical Gray Zone

Stem cells are special cells with the potential to repair damaged tissue and organs. Stem cell therapy involves using these cells in injections and tissue transplants to heal injuries and treat disease.

That's not as simple or straightforward as it might sound. There are several types of stem cells, and not all of them are possessed of equal power. Those that come from human embryos or are specially programmed in a laboratory can turn into any kind of cell—and in theory, repair any organ or tissue—in the human body.

But according to the current scientific consensus, stem cells taken from fully developed tissues (what scientists often refer to as "adult stem cells") can only turn into the type of tissue from which they came. The therapeutic potential of these adult cells is believed to be much more limited, because fat stem cells can only turn into fat, liver stem cells can only turn into liver, and so on.

Access to embryonic stem cells is federally monitored, but adult stem cells, which can be extracted from a patient's own body, are subject to relatively few federal regulations. As a result, doctors have generally been allowed to use them to treat a wide range of conditions without demonstrating that they're safe or effective.

"Stem cells have taken on this sort of mythic power in people's minds. But there are real limits to what most of these cells can actually do."

Sally Temple, Ph.D., scientist, the Neural Stem Cell Institute, Rensselaer, N.Y.

In fact, stem cell treatments are widely accepted only for two broad medical indications: to help treat a handful of blood disorders—including leukemia and some forms of anemia—and in some cases to help burn victims. "Stem cells have taken on this sort of mythic power in people's minds," says Sally Temple, Ph.D., a scientist at the Neural Stem Cell Institute in Rensselaer, N.Y. "But there are real limits to what most of these cells can actually do."

The FDA has acknowledged the problem of under-regulated stem cell medicine and says it is taking steps to strengthen its oversight of this burgeoning industry. Regulators have issued warning letters to numerous stem cell clinics for violating laboratory and manufacturing standards, and have ordered at least one company to stop selling stem cell-based products. In November it declared that going forward, agency approval would be required for some stem cell therapies (the way it is for prescription drugs) and that clinics where patients are harmed would be subject to enforcement actions, including increased inspections and possible product seizures.

Patient-safety advocates say those measures fall short of what's needed to protect consumers. "Clinics and doctors need to be prevented from selling dangerous untested medicine before they harm people, not after," says Lisa McGiffert, director of the Safe Patient Project at Consumers Union, the policy and mobilization division of Consumer Reports.

The FDA declined to make any of its representatives available for an interview for this article. But a spokesperson said by email that the agency is working to balance consumer protection with medical innovation, and that it is hopeful that doctors and clinics will comply voluntarily with the new framework.

A Climate of Confusion

There's no shortage of opportunity for consumers like John Rodolf to encounter the promise and peril of experimental stem cell treatments. They are being studied by blue-chip medical centers like the Mayo Clinic, offered in the exam rooms of dermatologists and orthopedists, and advertised in newspapers and online by more than 500 stem cell specialty clinics.

The level of scientific vetting these treatments have been subjected to runs the gamut. Some have been carefully developed and sanctioned by the FDA; others haven't been formally studied but have some evidence to support their use. Others still are untested and dangerously unscientific.

It can be difficult to tell which of those categories any given stem cell therapy falls into, in part because websites and advertisements that promote bogus treatments can look just as professional and trustworthy as the ones that discuss legitimate clinical trials. "I found out about the Lung Institute in a magazine advertisement in my doctor's office," says Maureen Rosen, a 75-year-old resident of Ocala, Fla., who, like John Rodolf, paid the Lung Institute thousands of dollars for COPD treatments she says didn't work at all. "And it looked impressive to me. And when I went online, the website looked like any other website that you'd see for a hospital."

Another problem is that questionable treatments are sometimes advertised alongside promising ones. For example, according to court documents and a case study published in the New England Journal of Medicine, three women suffered serious vision impairment (one went completely blind) after participating in a study they found listed at clinicaltrials.gov, a website maintained by the National Institutes of Health (NIH).

The site lists more than 1,000 stem cell-related clinical trials. Some of them have secured investigative new drug (IND) approval from the FDA, a process that can take years of research and involves careful vetting of protocols for safety and close monitoring of patients, as a rule. But other trials listed on the site haven't completed those steps, and there's no easy way to tell the two groups apart.

The clinical trial that allegedly cost the three women their vision was administered at U.S. Stem Cell Clinic (USSCC) in Sunrise, Fla. It involved extracting stem cells from the women's belly fat and injecting them into their eyes to treat their macular degeneration. Researchers say the protocol violated basic safety principles—such as treating only one eye so that the other would be spared in the event of complications—and that it used a type of stem cell that hasn't demonstrated any potential for treating macular degeneration. "Fat stem cells can only turn into fat," says Temple of the Neural Stem Cell Institute. "There's no reason to think they would do anything for diseases of the eye." U.S. Stem Cell Clinic declined to be interviewed for this article.

The NIH recently added a disclaimer to its clinical trials home page, warning that not all of the listed studies have been vetted by a federal agency. But critics say that notice isn't enough to protect consumers, many of whom are desperate for miracle cures. "Some clinics effectively use this site as a marketing tool," says Leigh Turner, Ph.D., a bioethicist at the University of Minnesota who has studied the stem cell industry. "They post studies there because it gives them an air of legitimacy, which in turn helps them attract patients."

An NIH spokeswoman told Consumer Reports that the government agency is considering additional measures to help consumers navigate the site better, but she didn't mention specifics.

"[Some institutions] use patient testimonials to promote treatments that have not been scientifically proven. They create the impression that even though it's experimental, it really works."

Leigh Turner, Ph.D., bioethicist, University of Minnesota

Stem cell scientists and patient-safety advocates say that stem cell specialty clinics are the most likely to sell untested therapies to consumers or to disguise questionable treatments as legitimate clinical trials. But even such well-known and trusted institutions as the Mayo Clinic, the University of California, Davis and Northwestern University have been accused of stem cell overhype. Some doctors and bioethicists believe that web videos touting clinical research at all three institutions run afoul of medical ethics. "They're using patient testimonials to promote treatments that have not been scientifically proven," says Turner. "They create the impression that even though it's experimental, it really works."

Northwestern University didn't respond to requests for comment. But a UC Davis spokesperson said that the intention of its video was for consumers to simply "learn more" about the school's work. And a Mayo spokesperson reportedly told Health News Review (a nonprofit that subjects health media to peer review) that the web video was meant not as an advertisement for stem cell therapy but to showcase promising research.

Victor Khabie, M.D., chief of sports medicine at Northern Westchester Hospital in Mt. Kisco, N.Y., says that some private-practice physicians (often in sports medicine and dermatology) are also guilty of selling stem cell injections that may have no therapeutic benefit, but that they're largely responding to patient demand.

"People hear about professional athletes who swear these injections cured their muscle damage or resolved their joint pain, and they come in wanting the same treatments," he says. "When done right, these particular injections are safe. But they're also very expensive, and there hasn't been enough research to say whether or not the effects are placebo effects." (A placebo effect refers to the tendency of any medical treatment, even a sugar pill, to produce some benefit simply because the patient expects it to work.) 

In Harm's Way

The women who suffered vision impairment after being treated at USSCC in Florida aren't the only patients to have allegedly been harmed by an experimental stem cell treatment. According to court papers filed by the Florida State Board of Medicine, at least one patient died after receiving stem cell injections to treat nerve damage from a Florida doctor whose license has since been revoked.

And according to the New England Journal of Medicine, a Massachusetts man was completely paralyzed after stem cells injected into his spine to treat a stroke-related disability morphed into a tumor. The article suggested that known cases of patient harm may only be the tip of the iceberg. Owing to a lack of reporting requirements, the paper's authors wrote, adverse events associated with unproven stem cell treatments are probably much more common than is currently known.

Paul Knoepfler, Ph.D., a stem cell researcher and industry watchdog at the University of California, Davis—who was not involved in the research promoted in the school's web video—says that consumers routinely underestimate the risks associated with stem cell injections. "People think that since the cells come from their own bodies, they must be safe," he says. "But oversight is so lax that there's no way to even know what you're being injected with half the time."

Last summer federal agents confiscated smallpox vaccines from StemImmune, a California company that specializes in stem cell-based immunotherapies for cancer. The company was mixing those vaccines with stem cells to create an experimental—and dangerous, the FDA says—cancer treatment. It was being used by doctors at the California Stem Cell Treatment Centers (CSCTC) in Rancho Mirage and Beverly Hills. StemImmune didn't respond to a request for comment. But Mark Berman, M.D., a co-founder of CSCTC, disputed the implication that his clinics were exploiting cancer patients or putting them at risk. "We have real board-certified oncologists evaluate these patients," he says. "And it was all free of charge." 

According to the FDA commissioner, Scott Gottlieb, M.D., shoddy stem cell medicine does more than imperil unwitting consumers; it also threatens to undermine real scientific progress being made. "Products that are reliably and carefully developed will be harder to advance if bad actors are able to make hollow claims and market unsafe science," he said in an Aug. 28 press release announcing that the agency would be issuing a new framework for stem cell regulations.

"People think that since the cells come from their own bodies, they must be safe. But oversight is so lax that there's no way to even know what you're being injected with half the time."

Paul Knoepfler, Ph.D., stem cell researcher, University of California, Davis

That framework, released in November, indicates that at least some stem cell treatments (namely those derived from belly fat) will now need FDA approval.

The International Society for Stem Cell Research has hailed the new measures as an important step toward better consumer protection. But whether they will usher in any meaningful change remains to be seen. The FDA says it will give companies and clinics three years to comply with the regulations, provided their treatments and techniques haven't been deemed a threat to patient safety. But the agency hasn't explained how—or even if—it will determine which doctors and clinics are putting consumers at risk. And it hasn't clarified what will happen to clinics that don't comply within the three-year time frame.

According to the guidelines, treatments injected directly into the bloodstream or central nervous system will be considered more dangerous than those injected into joints or skin. But in a press conference this past November, Peter Marks, M.D., Ph.D., director of the FDA's center for biologics evaluation and research (CBER), implied that punitive measures would be taken only after patient injuries or illnesses were reported. "There are literally hundreds and hundreds of these clinics," he said. "We simply don't have the bandwidth to go after all of them at once. So the judgment here is to go after the ones where we have documented instances of harm."

In the meantime, John Rodolf and Maureen Rosen say that after many months of waiting for their stem cell treatments to kick in, they gave up and tried more conventional approaches. Rodolf says that losing weight has helped improve his breathing. And Rosen now pays $48 a month to go to pulmonary rehab, where she gets physical therapy three times a week. Her breathing has improved enough that she can remove her oxygen tank for small portions of her day. "I wish someone had told me to try this first," she says. "It's a lot cheaper, and it actually works."


How to Protect Yourself

The FDA, the International Society for Stem Cell Research, and CR's medical experts advise you to be cautious when considering stem cell therapy.

Beware of the hype and hefty fees. Doctors testing stem cell treatments in carefully controlled clinical trials usually don't promote their offerings with big, flashy advertisements that promise dramatic improvements or total cures. They also don't charge a lot. There may be some minor fees for travel or other personal expenses, but the treatment itself should be free or low-cost to participants. "A large price tag—especially in the range of thousands of dollars—should be a major red flag," says Marvin M. Lipman, M.D., Consumer Reports' chief medical adviser. So should any doctor claiming to treat a wide range of medical conditions, such as autism, arthritis, and erectile dysfunction, with the same therapy. Different organs and body systems require different expertise—and different medicine—to treat, which is why most doctors specialize.

Ask questions. Any doctor who offers stem cell therapy should be able to explain where the cells will come from, what will be done to them before they're injected into your body, and how, exactly, they will resolve your illness or injury. He or she should also be able to offer you proof of safety and efficacy, even for experimental treatments. Don't settle for patient testimonials. Ask how many people the proposed therapy has been tested on (the more the better) and whether those tests were done in clinical trials or as individual case studies. (Randomized controlled trials, where people given a treatment are compared with a control group that wasn't, are best.) It's also important to find out what the outcomes were. (Ideally, side effects were minimal and significantly more people improved than did not.)

Read the fine print. If the treatment is being offered as a clinical trial, make sure the trial has been vetted by the FDA, a process known as securing investigative new drug (IND) approval. The agency advises that you ask to see the actual approval letter to make sure it has been issued specifically for the treatment you're considering. Treatments that have cleared this hurdle are much more likely to be safe than those that have not. You should also make sure that any informed consent document (an explanation of the experimental treatment that study participants are usually asked to sign) provides a clear description of the treatment being offered along with the risks, alternative options, and details about what to expect in the days and weeks after the procedure. It should not indemnify doctors or their institutions against liability for negligence.

Correction: A previous version of this story incorrectly stated that Mayo Clinic did not respond to a request for comment. In fact, Mayo Clinic did respond.