By Prateek Buch, on 4 February 2013
Stem cells – cells that have the capacity to turn into virtually any cell in the human body – are an exciting source of potential treatments for a huge range of medical conditions. Stem cells are already being used in the treatment of disorders of the blood. Academics, clinical specialists and companies throughout the world are developing treatments for other conditions, including many that cause sight loss. Our own group has begun testing the safety of transplanting retinal cells grown from stem cells in patients with Stargardt disease.
Unfortunately there are a number of ‘stem cell therapies’ that are being promoted as proven treatments, without scientific evidence or appropriate approval. Here we aim to help those considering stem cell therapy for sight loss to distinguish between the approved experimental techniques in clinical trials, and the bogus treatments being offered elsewhere.
It’s important to remember that no stem cell treatment has been approved for eye disease by the medical authorities. This is because clinical trials involving stem cells in the eye are at the very earliest stages, and it is too early to know whether their use is safe or effective. Until such trials are completed, any treatments on offer are likely to be unproven.
There are a number of clinics and companies that offer what they describe as stem cell transplants for a wide range of conditions, often at significant cost. These transplants have not been subject to the rigorous safety checks that are part of properly-conducted clinical trials. The clinics offering them are usually located in countries with less stringent standards of safety and regulations than we expect in the UK, enabling them to sell such treatments in the absence of published scientific evidence to support them.
The treatment typically involves the injection of stem cells (or rather cells that come from bone marrow, or the umbilical cords of newborn babies) without first turning them into a particular cell type. The difference between these cells and cells we are using in our clinical trial is a subject for another day, but for now it’s worth remembering that the cells in our studies are first made into retinal cells in a dish before being delivered into the eye. There is no evidence that stem cells injected into the body can reach the eye, or that once they do they can repair any damage. Furthermore, there is a very real possibility that such cells could cause harm by proliferating uncontrollably.
Companies offering these injections often feature patient testimonials, which are not a reliable indicator of safety or efficacy. The only reliable, peer-reviewed, published account of a patient receiving such transplants that we are aware of shows very clearly that there was no way to tell what kind of cells were injected, and that there was no effect whatsoever on vision after treatment.
In the absence of any scientific evidence supporting the direct injection of stem cells, we cannot recommend any of the treatments currently on offer. Should you be considering any such treatments, we strongly recommend that you check our Frequently Asked Questions and contact us first for advice.