More than 500 clinics across the United States are marketing unapproved stem cell treatments for conditions ranging from Alzheimer's to cosmetic enhancements, a new study finds.
In an online survey, researchers found at least 570 clinics offering unapproved stem cell "therapies" in states across the country.
Most often, the clinics market stem cell procedures for orthopedic conditions, such as arthritis and injured ligaments and tendons. This does have science behind it, but is still experimental, medical experts said.
"In almost every state now, people can go locally to get stem-cell 'treatments," said Paul Knoepfler, a stem-cell scientist at the University of California at Davis School of Medicine and one of the authors of the study, published Thursday in the journal Cell Stem Cell.
"What worries us is the possibility of serious harm to patients," said co-author Leigh Turner, an associate professor at the Center for Bioethics at the University of Minnesota.
"I think there's a misperception that everything here [in the US] is regulated," Turner said. "But these clinics are operating here unregulated, and on a relatively large scale."
Stem cells are primitive cells with the potential to mature into various types of body tissue. Medical researchers have been studying the possibility of using stem cells to repair damaged tissue in a range of chronic ills -- with limited success so far.
Arthur Caplan, a bioethicist who was not involved in the study, said it’s known that some patients have been seriously harmed during the stem cell treatments.
"Many of these claims are outrageous," Caplan said. "These clinics are preying on vulnerable people."
The US Food and Drug Administration (FDA) has approved only a few stem-cell treatments and says treatment for most conditions are still largely unproven.
The FDA is now taking steps against specific clinics. Last year, it sent a warning letter to a network of companies that operate in California, New York and Florida.
"In theory, stem cells may advance the treatment of many other diseases or conditions; however, at this time, the value of stem cells as a treatment for most conditions is largely unproven and more information is needed about their potential benefits," the FDA said in a statement.