Three women went blind after receiving an unproven stem cell treatment on their eyes at a Florida clinic, according to a new report of the cases.
The women, in their 70s and 80s, all had macular degeneration, a progressive eye disease that leads to damage of the retina, and can cause vision loss. They underwent the stem cell therapy in 2015, in the hopes that it would treat their disease.
However, there's no evidence that the stem cell treatment the women received can help restore vision in people with macular degeneration, wrote the authors of the new report. Several of the report's authors treated the women for complications after the stem cell treatment; none of the authors were involved in the original treatment.
In addition, there is a lack of information on the safety of this treatment, and some of the techniques used by the Florida clinic were unsafe, the report said. Shortly after the procedure, the women experienced a number of complications, including vision loss, detached retinas and bleeding. [7 Medical Myths Even Doctors Believe]
"There's a lot of hope for stem cells, and these types of clinics appeal to patients desperate for care, who hope that stem cells are going to be the answer," Dr. Thomas Albini, an associate professor of clinical ophthalmology at the University of Miami and a co-author of the report, said in a statement. "But in this case, these women participated in a clinical enterprise that was off-the-charts dangerous," Albini said.
What's more, some of the patients believed they were participating in a clinical trial of the stem cell treatment, according to the report. And they had good reason to think so — a trial describing this treatment was listed on the website ClinicalTrials.gov, a registry database run by the U.S. National Library of Medicine. However, the consent forms that the women signed before they underwent the procedure did not mention the trial, and the patients were required to pay $5,000 for the procedure. Patients who participate in clinical trials typically do not need to pay to do so, the researchers said.
"I'm not aware of any legitimate research, at least in ophthalmology, that is patient-funded," Albini said.
The researchers wrote that they hope their report raises awareness about the potential risks of these types of procedures performed at for-profit stem cell clinics that lack data to support their practices. The report is published today (March 15) in the New England Journal of Medicine.
In recent years, there has been a rise in clinics offering unproven stem cell treatments in the United States. There are now calls for more regulation of these clinics, and last year, the Food and Drug Administration proposed new rules that would require a more rigorous approval process for using such treatments in patients.
At the Florida clinic, called U.S. Stem Cell, Inc. (formerly BioHeart, Inc.), the three patients received a treatment that uses cells called adipose tissue-derived stem cells. For this treatment, the patients had fat cells removed from their abdomens, and this tissue was then processed with enzymes, which the company said would isolate stem cells. These cells were then mixed with a sample of the patient's own blood plasma that was enriched with platelets (a component of blood that aids in blood clotting). This mixture was then injected into the patients' eyes.
Each patient had both eyes treated at the same time, but this protocol is unsafe, the new report said. Most doctors using any experimental eye treatment will treat only one eye at a time, to see how the eye responds to the treatment, the researchers said.
All three patients are now blind, and it is extremely unlikely that they will regain their vision, Albini said.
The complications seen in these patients are likely due to the stem cell preparation they received, the report said. For example, it could be that the material injected into the patients' eyes was contaminated with an enzyme that can damage the eye. Another possibility is that, when they were injected into the eye, the stem cells transformed into myofibroblasts, which are cells that are linked with scarring, the authors said.
In a statement to Live Science, U.S. Stem Cell said it could not comment on specific patients' cases due to "patient confidentiality or legal confidentiality obligations." The company said that since 2001, its clinics have conducted "more than 7,000 stem cell procedures with less than 0.01 percent adverse reactions reported." The company also noted that it does not currently treat eye patients.
In 2013, the company listed a trial on ClinicalTrials.gov titled, "Study to Assess the Safety and Effects of Cells Injected Intravitreal in Dry Macular Degeneration," according to the ClinicalTrials.gov site. However, the current listing for this trial says, "This study has been withdrawn prior to enrollment." In other words, the company claims the study was stopped before patients were enrolled.
It's important to note that stem cell therapies do hold promise for treating a number of human diseases, the case reports' authors said. And there are numerous institutions conducing legitimate clinical trials on stem cell therapies that have appropriate safety and regulatory oversight. However, it can be difficult for patients to distinguish between trials that are legitimate, and those that are not, the authors wrote.
Dr. Jeffrey Goldberg, a professor and chair of ophthalmology at the Stanford University School of Medicine, who co-authored the new report, recommended that patients considering stem cell treatments consult the website A Closer Look at Stem Cells. It is maintained by the International Society for Stem Cell Research and contains information on stem cell therapies.
Goldberg also recommended that patients check if a trial is affiliated with an academic medical center.
Original article on Live Science.
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Rachael is a Live Science contributor, and was a former channel editor and senior writer for Live Science between 2010 and 2022. She has a master's degree in journalism from New York University's Science, Health and Environmental Reporting Program. She also holds a B.S. in molecular biology and an M.S. in biology from the University of California, San Diego. Her work has appeared in Scienceline, The Washington Post and Scientific American.