Stem Cell Therapies: Are We Blinded by Perception or Focused on Reality?
Is there a stem cell therapy for [insert disease here]? The question arises nearly every day and it is not surprising given the abundance of articles and advertisements promoting the use of “stem cell treatments” for a staggering number of diseases and injuries. A quick search of the internet brings up a long list of clinics offering what appear to be stem cell solutions for a wide variety of medical problems.
The sheer number of clinics offering these solutions fosters the perception that medically-accepted stem cell-based treatments are available for nearly every disease or injury. However, the reality is that there are currently only a few stem cell-based treatments that have been rigorously tested and scientifically proven to be safe and effective.
The rigorous testing of emerging potential therapies takes time, including testing in formal clinical trials, as well as a formal regulatory review process. This time-tested process is necessary to ensure that cellular products are safe and effective before they are marketed to consumers.
Clinics offering unproven therapies are perpetuating a myth that autologous treatments—those that use cells from one’s own body, such as body fat don’t need to go through this process because they are naturally safe since the cells are from one’s own body and they are effective because stem cells have an innate ability to sense, locate and treat cell and tissue damage.
This is not true. In fact, all treatments need to be proven safe and effective and have associated risks. Cellular therapies have a unique set of risks as compared to more traditional drug-based treatments.
Cellular therapies use living cells that are biologically active: they have the potential to migrate through the body, they can secrete other biologically active molecules, and they may live indefinitely, even in tissues where they are not normally found. These factors and others can impact the safety and efficacy of any cell-based treatment.
There are several factors to consider when evaluating whether a cell therapy will be effective. One of the most essential is the need to characterize the cells being used. How are these cells identified and isolated? How reproducible is this process? How are the cells exerting an effect – are they secreting something in the body or are they replacing dead or damaged cells in the area of the injury or disease?
Additionally, how many cells are needed for the treatment to be effective? In many systems, as stem cells age they decline in number and function, making standardization of treatment between younger and older patients difficult. These questions must be part of the evaluation process.
Several stem cell-based interventions are currently working their way through the formal clinical trial process. In at least one example, the methodical process of testing a potential therapy for age-related macular degeneration (AMD) uncovered a potential safety risk which temporarily suspended the trial until the potential risks could be assessed.
While critics may contend the testing and approval time unfairly delays or blocks the availability of life-saving treatments, the risks of using cell-based products that have not been tested can be high, even for those who believe they have nothing to lose.
A recent tragic report of three people being blinded or nearly-blinded by a “stem cell treatment” is just one example. The process used cells from each patient’s own fat, manipulated in some way and then injected into both eyes. Rather than treating the underlying AMD, the procedure worsened the vision of all three patients. This is only one of many examples of autologous cell “treatments” that have given rise to significant adverse effects. While not all patients will have serious side effects, the risks (and benefits) of untested “treatments” are not always fully understood.
As with many medicines, cell-based treatments, even those that have been reviewed, approved, and rigorously tested, have risks. However, the clinical trial process is designed to assess those risks and to mitigate and minimize them for the patient. Unproven therapies are just that—unknown, untested, and risky.