A team of ophthalmologists says the amount of harm being done by unapproved stem cell therapy is underreported.

The team went looking for scientific evidence in support of commercially available “cell therapy” for eye diseases after one of the ophthalmologists lost the battle to save a woman’s sight after undergoing an unapproved treatment for macular degeneration. Not only did they find virtually none; they instead discovered a growing number of patients are being irreparably harmed by unapproved cell therapies.

The ophthalmologists leading the study, Drs Ajay Kuriyan and Andrew Chen, and colleagues at the University of Rochester’s Flaum Eye Institute and the University of Miami’s Bascom Palmer Eye Institute reviewed evidence supporting cell therapy published in scientific journals and from the clinics’ websites and marketing materials. Their review of published studies found only a few case studies, involving a total of 18 patients. All patients were reported to have had positive treatment outcomes or no improvement. However, the researchers were able to identify at least seven patients who had experienced devastating harm from an unapproved cell therapy.

The number of clinics administering stem cell therapies not authorised by the Federal Drug Administration (FDA) has proliferated in recent years, with nearly 600 clinics opening in the United States alone. The clinics claim to help patients suffering from a broad range of conditions including age-related macular degeneration, Parkinson’s disease, autism and multiple sclerosis.

In May, the FDA began cracking down on clinics marketing unapproved therapies after three women with macular degeneration lost their vision after undergoing an unproven stem-cell treatment at a Florida clinic.

“When you look at these company’s websites and their publications, you’ll see a big under-reporting of profound complications,” said Dr Kuriyan. “This is in stark contrast to what we have seen in our clinics and in our personal experience. There’s a fairly significant number of patients who experienced poor, or in some cases devastating results. The cases published to date just scratch the surface of the number of bad outcomes.”

The cell therapy clinics are not only endangering patient health, Dr. Kuriyan warns, they are also threatening to undermine both legitimate scientific progress and the public’s trust in stem cell research.

To help patients identify legitimate research, Dr. Kuriyan advises against joining studies that require payment. Centers or clinics that only offer cell therapy is another red flag, Dr. Kuriyan said. A reputable clinic will offer a variety of treatments for conditions.  Most importantly, he recommends patients ask questions and discuss potential treatments with their ophthalmologist.

Dr Kuriyan and his colleagues are currently collecting data for a larger study, detailing all the patients who suffered complications from unapproved cell therapy.