In two days of hearings next month, the U.S. Food and Drug Administration will consider if clinics offering stem-cell treatments should be more closely regulated.

Stem-cell treatments aren’t approved by the FDA and not long ago, Americans had to travel to Mexico, China or elsewhere to receive them. Now, with the regulatory environment murky, clinics offering them are spreading rapidly across the U.S. A recent report in the journal Cell Stem Cell counted 570 clinics advertising stem-cell therapies directly to consumers. Many claim to treat a long list of disorders, from arthritis to Alzheimer’s disease, even though the stem-cell treatment for many of the conditions hasn’t yet been tested on humans. Treatment typically costs thousands of dollars.

Critics, including many top stem-cell scientists, say the clinics are peddling 21st century snake oil and want the FDA to crack down. Clinic operators say they don’t need FDA approval because they are practicing medicine, not creating new drugs. Some patients say they have been helped and that the government shouldn’t regulate what they do with their own cells.

Stem cells, found in both embryos and adult tissues, offer enormous promise to scientists because they have the potential to develop into many different kinds of cells or serve as the body’s own repair service. Research is exploding into ways stem cells might be harnessed to cure diseases, mend damaged tissue, even grow replacement organs.

But most such research is still in the early stages. To date, the FDA has approved only a handful of stem-cell treatments, mainly for blood diseases such as leukemia. Scientists say much more work needs to be done to understand how stem cells work and what uses are safe and effective.

“We need to make sure that these technologies are reliable and reproducible, time and time again, before you put them into patients,” says Anthony Atala, director of the Wake Forest Institute for Regenerative Medicine in Winston-Salem, N.C., which has 450 researchers working to create new tissues from stem cells.

“This is the future of health care, using your own stem cells to fix problems, not drugs,” says Paula Grisanti, chairwoman of the National Stem Cell Foundation, a nonprofit that funds many research projects. “But clinics that make over-the-top claims that a single stem-cell therapy will cure ALS or Parkinson’s or other diseases raise huge safety and ethical concerns. It gives the whole field a black eye.”

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