The authors of a study detailing the rapid expansion of unlicensed stem-cell therapies in the US have called on the Food and Drug Administration (FDA) to act to stop thousands of patients being used as 'unwitting guinea pigs' for untested treatments.
In a study published in the journal Cell Stem Cell, Professor Paul Knoepfler and Dr Leigh Turner identify 351 companies marketing unapproved procedures at 570 clinics across the US.
While the majority of companies concerned offer stem-cell treatments for orthopaedic issues, at least 80 advertise stem-cell treatments for neurological diseases like Parkinson's and Alzheimer's diseases.
Dr Turner, an associate professor of bioethics at the University of Minnesota, said: 'Brakes ought to exist in a marketplace like this, but where are the brakes? Where are the regulatory bodies? And how did this entire industry come into being in a country where stem cell-based interventions and the medical devices that produce them are supposed to be regulated by the FDA?'
A decision from the US federal court in July 2012 effectively confirmed the FDA's authority to regulate stem-cell therapies in the same way as it does pharmaceuticals (see BioNews 667), but the regulatory guidelines it will use to police the sector are still being prepared. The FDA is due to have its next public hearing on the matter in September.
Dr Turner says that for about seven years now companies have been taking advantage of this regulatory void and 'making marketing assertions about stem cells treating 30–40 different diseases, and no one's taking meaningful regulatory action'.
Speaking to The Guardian, Dr Turner highlighted the 'pretty dramatic claims' of treatment for currently incurable diseases that his study uncovered, while in fact none of the procedures offered had been tested in clinical trials.
'In a way people are almost uninformed and unwitting guinea pigs,' he said. 'They are research subjects but no one is telling them that.'
The majority of clinics identified by the study offered treatments using the patients' own stem cells with no promise of any genetic modification. However, one business did offer treatments with induced pluripotent stem cells, another with embryonic stem cells, and two businesses offered stem cells from different animal species.
Professor Knoepfler, a stem-cell researcher at the University of California at Davis, said that his peers in stem-cell research should be concerned about the study's findings: 'There is a real risk that as clinics proliferate, if we don't address it in a more proactive way, as we see negative outcomes for patients grow and people get mixed bags of information about stem cells, then this could really negatively impact the public perception of this research.'