Stem cells can fight disease from the inside out. But not all treatments are created equal.
The promise of stem cell therapy is powerful. Scientists can draw versatile cells from the human body and deliver them to repair injuries and fight disease from the inside out.
But not all stem cell therapies are created equal. Some, like bone marrow transplants, are supported by decades of clinical research and are considered safe and effective. Others are still in clinical trials, meaning they’re promising concepts but have not yet been put into practice. At the same time, medical spas and longevity clinics are increasingly marketing their own stem cell treatments for arthritis, joint pain, Parkinson’s disease, A.L.S. and even better skin.
Scientists warn that the treatments being touted by these spas and clinics are all unproven, expensive and could come with dangerous side effects.
“This clinic industry poses all kinds of risks to the public,” said Paul Knoepfler, a professor at the University of California Davis School of Medicine who studies stem cells.
Some stem cell experts, including Dr. Knoepfler, are worried that the F.D.A. may loosen oversight on stem cell therapy, which could confuse the public about the difference between scientifically supported treatment and untested therapies.
Their concerns come in part from Health Secretary Robert F. Kennedy Jr.’s remarks on the subject, including a post on X in October calling for an end to the F.D.A.’s “aggressive suppression” of stem cell therapies. During a recent podcast with longevity influencer Gary Brecka, Mr. Kennedy said that he had traveled to Antigua to get a stem cell treatment for his throat. Mr. Kennedy, who has a neurological condition that affects his throat and voice, said the therapy helped him “enormously.”
“Why did I have to go to Antigua for that?” he said, suggesting that he would work to expand access to stem cell treatments and other experimental therapies.
How are stem cells regulated right now?
Companies developing stem cell therapies can apply to the Food and Drug Administration for authorization to begin studies in humans. If the therapy appears to work, the company can then seek approval from the F.D.A., which reviews the data on the treatment.
In addition, F.D.A. has the power to regulate the products offered at private clinics, which have generally not been approved. The agency has previously demanded some clinics stop selling unproven stem cell treatments that could harm patients or cause them to delay more legitimate treatment.
Less regulation, though, may mean less oversight of companies “charging a lot of money for something that’s not really been validated,” said Clive Svendsen, a professor of biomedical sciences who leads a stem cell research lab at Cedars-Sinai in Los Angeles.
Why are scientists excited about them?
Stem cells are the blank cells that all tissues and organs in your body are created from. Unlike many other cells, certain stem cells can also regenerate. Because of that, scientists think they could offer an endless supply of cells that can be manipulated to replace other types of cells in your body that have been damaged.
Some treatments rely on adult stem cells harvested from blood or bone marrow. Others use regular skin or blood cells which are reprogrammed into stem cells in a lab.
For approved therapies, these stem cells are typically manipulated in a lab to become a certain type of cell, and then delivered into specific tissues in the hopes that they replace lost or injured cells, said Tenneille Ludwig, director of the WiCell Stem Cell Bank in Wisconsin, which distributes cells used in research and clinical trials.
What treatments are available and what’s being studied?
Only a handful of stem cell therapies are currently approved by the F.D.A., mainly for treating blood cancer and immune system disorders. (Some therapies, for conditions like corneal damage or arterial disease, are approved in other countries but not in the United States.)
In bone marrow transplants, one of the F.D.A.-approved treatments, a donor’s stem cells are injected into a patient, where they become blood or immune cells that can replace the ones damaged by chemotherapy or radiation treatment.
One ongoing clinical trial is investigating whether stem cells can replace the dopamine-producing neurons that die out during Parkinson’s disease, which could potentially reverse the symptoms. Another is looking at whether insulin-producing cells derived from stem cells can be used as a diabetes treatment.
And there’s other research that some scientists see as promising. Studies have suggested that stem cells that have been reprogrammed into blank cells and then into heart cells may be able to restore some cardiac function. Larger trials on neurological and cardiac treatments — including for A.L.S. and heart failure — are ongoing, but have so far fallen “short of expectations,” said Jeffrey Karp, chair of the anesthesiology department at Mass General Brigham and Harvard Medical School.
What about the experimental treatments at private clinics?
Thousands of clinics around the country now offer what they claim are stem cell treatments for a wide range of diseases. These treatments are not covered by insurance, and can cost between a few thousand to tens of thousands of dollars per injection, Dr. Svendsen said.
Typically, these clinics draw stem cells from the patients’ body or a donor, sometimes from their fat, and inject them back into the patient without any manipulation, experts said. (This can allow companies to skirt the F.D.A., which does not regulate some stem cell treatments if providers say they are only minimally manipulating a person’s own cells.)
If these treatments do happen to offer some relief, “it’s very likely that it’s a placebo,” Dr. Svendsen said, adding that there’s no sound scientific explanation for why stem cells that haven’t been manipulated into more specific cell types would offer any health benefits. “They’re just asking you for $7,000 to have your cells infused back into your body.”
There are other risks to consider. First, there’s no guarantee that clinics use true stem cells, Dr. Karp said: While they may be collecting cells from a patient or donor’s bone marrow or fat, there’s no assurance that the cells they collected are the ones that regenerate.
Clinics also aren’t required to report where the donor stem cells came from, which means they could be contaminated, Dr. Karp said. In addition, improper injections — and contaminated cells — could lead to serious health problems like clots or cells traveling to the wrong organs in the body, the experts said. The F.D.A. has previously warned of reports of blindness, tumor formations and infections after unapproved stem cell treatments. In 2017, three patients in Florida had permanent vision damage after stem cells were injected into their eyes in an attempt to treat macular degeneration.
“Of course you’re going to get a lot of charlatans, and you’re going to get people who have bad results,” Mr. Kennedy acknowledged on the recent podcast appearance. “And ultimately, you can’t prevent that either way.”
Dr. Karp said that “the most dangerous scenarios tend to occur at for-profit clinics operating without oversight.”
“These clinics often make exaggerated claims and skip crucial safety protocols,” he said.
While people with chronic pain or other illness may be desperate for relief, these unproven treatments pose a “serious possibility of injury,” Dr. Ludwig said, adding that patients should ask what regulatory protocols clinics follow, and the extent to which scientific literature supports their treatments. “I would be very wary.”
