In the USA, clinics offering stem cell therapies not approved by the US Food and Drug Administration (FDA) expanded four-fold in just five years. These putative medical treatments lack concrete evidence of safety and efficacy, a study published in the journal Cell Stem Cell earlier this year has shown.
Stem cell research is incredibly important for providing insight into diseases such as Parkinson's, with the hope this might provide potential targets for future treatment. But there's a caveat: much work is still necessary both to discover the mechanisms behind these diseases, and where we do understand the mechanism to translate this research into safe and effective therapies. Currently, the range of illnesses for which there are proven treatments based on stem cells is minuscule. The only established safe and effective stem cell treatment is haematopoietic stem cell transplantation which is used for treating conditions including leukaemia and multiple sclerosis. Any other stem cell therapies are currently unproven and experimental and require full independent review and testing to make sure they are safe and effective.
Despite scant evidence for their safety or efficacy, some for-profit private clinics, which are skipping the usual clinical trials and approval processes for medicines, promote so-called stem-cell-based treatments on the internet. Many of the procedures offered are with autologous stem cells which are stem cells removed from the patients' body. Some offer allogeneic stem cell transplants which are from other people, and some stem cell transplants with tissues derived from birth tissues such as umbilical cord blood transplant.
In his study, Professor Leigh Turner a bioethicist at the University of California, Irvine identified 1480 US businesses and 2754 clinics promoting purported stem cell therapies for various conditions. In his previous research performed in 2016, he found 351 companies and 570 clinics, a significant expansion in the number of such businesses operating in this space. Thus, the USA currently has more businesses offering untested stem cell treatments than any other nation, including those which were once the primary destinations for stem cell tourism, eg, developing countries with less regulation or weak enforcement.
Leading the nation with the highest numbers of such clinics are the states of California (347), Florida (333) and Texas (310), more than one-third of all stem cell clinics identified in the study. It is not too surprising with the first two states, the numbers are high; California has several cosmetic surgery clinics offering treatments such as 'fat grafting' where fat is removed from the abdomen and injected into the face to generate new skin cells, Florida has relatively large senior populations who are likely to have comorbidities such as Parkinson's disease and seek stem cell treatments for that. Interestingly, while Florida has a smaller population than Texas (21.5 million versus 29 million), it has more clinics offering unlicenced stem cell treatments than Texas.
Despite comprehensive FDA regulations on cell-based interventions, marketplace expansion has occured. While there are stem cell products that fall within the same indication and minimally manipulated cellular products used in a homologous manner that do not need premarketing review and licensure by the FDA, many of these interventions are categorised as biologics, drugs or medical devices which require safety and efficacy testing in clinical trials as well as FDA premarketing authorisation, which they have not received.
Turner found that the kinds of medical treatment offered are wide-ranging, from making claims to relieve pain, orthopaedic diseases and sports-related injuries to hair loss and anti-ageing. On a disturbing note, there were even clinics that claimed to enhance the human immune system to protect against the coronavirus.
Moreover, his analysis reveals that patients have incurred considerable expenses on these unproven products costing between US$1200 to $28,000, with an average price of around $5118 and the median price was $4000. The majority of patients pay for these treatments out of their own pocket.
Most concerning is that these unapproved stem cell products have caused adverse events to some patients. Some of them suffer severe damage, such as blindness. Yet, adverse events arising from these unproven stem cell products are likely to be underreported to the FDA, an article in the journal JAMA last year claimed.
In recent years, the US Congress passed two pieces of legislation; the 21st Century Cures Act 2016 and the Right to Try Act 2018 that aimed to expand patient access to experimental treatments. These changes in the law could have contributed to the expansion of the stem cell clinic industry across the nation.
Also, in November 2017, the FDA exercised enforcement discretion for three years to give the clinics offering unproven stem cell treatments ample time to determine where their products actually require FDA approval. However, owing to the pandemic, this grace period was extended until May 2021. During this period, there was a marketplace boom of these businesses selling unlicensed stem cell interventions.
Professor Turner also pointed out that his research tools have improved since the earlier study conducted in 2016 and this is likely to have contributed to improved and refined detection methods, accounting for some of the growth outlined in his paper.
Professor Turner is concerned that this trend is likely to remain. As a result, he believes there is a strong need for considerable enforcement measures by regulatory bodies such as the FDA and the Federal Trade Commission. For example, the FDA could continue to issue warning letters and file court injunctions to shut down these clinics. It remains to be seen how this will unfold in the coming years.