In the early 1920s, John Romulus Brinkley, an entrepreneurial Kansas physician with dubious professional credentials, ran a lucrative business implanting goat testicles under the skin or in the scrotum or abdomen of patients who sought his help for any one of twenty-seven ailments, including flatulence. He was one of many medical hucksters who took advantage of an unregulated medical world in the United States at that time and made fantastic claims for their medical treatments, potions, and elixirs. Eventually, Brinkley’s medical license was revoked by the state of Kansas, and he moved south to Texas, where he advertised his services via a folksy radio station broadcasting from just over the border in Mexico. His station’s powerful antenna beamed his ads and promises all the way to the Canadian border, drawing patients south for his “treatments.” In the end, Brinkley is said to have made millions of dollars before a federal grand jury indicted him in 1941 for postal fraud. He died, bankrupt, in 1942, before he ever stood trial.
Fast-forward to a well-regulated medical world in December 2014. A famous ex-hockey player suffers a stroke and travels to Mexico for stem cell treatments. His family claims great results, and his therapists corroborate the reports, leaving many who read the story to wonder whether their brain-damaged relatives could also benefit from this therapy and why they would have to travel to Mexico to get it. Is this the same type of treatment being offered, without FDA approval, at the new stem cell clinics popping up in many American cities? And why is stem cell treatment not FDA approved? The answers require some understanding of stem cell research, clinical trials of new therapies, and the reasons why the FDA exercises caution when approving novel therapies.
What are stem cells?
Stem cells begin in a fertilized human egg, which splits into two cells, then again into four, and again into eight, and on and on. The first few dozen cells have the potential to become any type of cell in the body and are called embryonic stem cells. As the fetus develops, cells begin committing themselves to different roles, shaping a human body with all its complex organs. Some cells in each organ, however, retain enough of their primitive character to serve as a reservoir of cells for the repair and growth of the organ. These cells are called adult stem cells. The term “stem cell treatment” might refer to procedures involving either type of stem cell, but the stem cell therapies being offered commercially are adult cells.
The hope of stem cell therapy
The promise of adult stem cell therapy is based on the hope that stem cells can be harnessed to perform on demand and develop into mature cells to replace aging or damaged cells. In an ideal world stem cells could be coerced to act like the stem cells residing in bone marrow do naturally and regularly. Marrow stem cells make new blood components continuously – red blood cells, white blood cells, and platelets. They must do so because blood cells have life spans of only a few weeks.
Bone marrow transplants were the first stem cell treatments. They were used successfully in treating blood cancers and worked by replacing the patient’s bone marrow with that of a healthy donor. Bone marrow contains many types of blood and immune cells, but it is the stem cell component that repopulates the patient’s diseased marrow after it has been wiped out by chemotherapy. Originally, drugs were needed to keep the body of a recipient of a bone marrow transplant from rejecting the foreign cells, but advances in doctors’ ability to separate healthy stem cells from all the other bone marrow components now make it possible for physicians to give the patient his or her own cells, making antirejection drugs unnecessary.
The discovery that stem cells existed in many different tissues widened research horizons and raised hopes that stem cells could be used to repair and regenerate more tissues than just bone marrow. A wide variety of stem cell experiments aimed at treating a number of diseases, including multiple sclerosis and heart disease, are now being conducted. Ongoing clinical trials at academic medical centers are enrolling patients under strict protocols. Such trials are the only objective way to establish the safety and efficacy of stem cell treatments compared to standard care and to placebos. But so far, these trials are still ongoing, and the FDA has only approved marrow and umbilical cord blood stem cell use for the treatment of blood diseases like leukemia and lymphoma.
The hype: what are stem cell clinics selling?
But what about the stem cell clinics in the United States that offer treatments for a wide range of diseases related to aging, including diseases such as Parkinson’s disease, Alzheimer’s disease, chronic lung disease, and cardiac disease? These clinics are entrepreneurial ventures that operate without FDA approval. Stem cells are not considered drugs because they are harvested from the patients own body for re-injection into it; therefore, the FDA has no jurisdiction over the hundreds of stem cell clinics operating in the United States. If trouble occurs in these clinics (and it has, including death) then state medical boards are responsible for policing the people providing services until some kind of FDA regulation is put in place.
Fat is the usual stem cell source
Today’s stem cell clinics appeared after the discovery that fat was one of the richest sources of adult stem cells. With the purchase of a cell separator and participation in a weekend seminar, any doctor can open a stem cell clinic. During stem cell treatments, fat is harvested from each patient through a version of the liposuction process. The stem cells that reside deep in the fat, near blood vessels, are concentrated in the cell separator and mixed with the patient’s plasma to cause the stem cells to begin to divide and grow. Some clinics also obtain marrow stem cells through a large needle inserted into the bone of the hip, and, in some clinics, lasers are used to activate the stem cells and raise them from a dormant state to a reproductive one. Treated cells are then injected back into the patient, into the bloodstream, under the skin, into a joint, or into the spinal fluid. In theory, these cells find their way to the targeted, ailing tissues, turn into the desired cell type – such as knee cartilage – and heal the problem. Some practitioners, however, believe that the stem cells may not propagate themselves but only stimulate the body’s natural repair processes.
Stem cell clinic literature often gives the impression that these procedures are risk free, but, in fact, all invasive medical procedures carry some risks, like infection and adverse effects such as dizziness. Recently several patients became blind after stem cell injections aimed at curing threating the macular degeneration in their retinas. Risks and side effects should be disclosed to every patient, even if their rates of occurrence are low.
No long-term follow-up studies available
Stem cell treatment is so new that there have been no long-term follow-up studies done on large numbers of patients, the type of studies that are used to uncover unexpected trouble with new procedures. Since stem cells are meant to reproduce and grow and since manipulating them outside their natural environments and injecting them into patients presents a risk of changing the programming that keeps their reproduction under control, long-term follow up studies over many years are essential. While some stem cell clinics purport to do studies on patient outcomes, they demand that their patients pay for their treatments, and no legitimate study would require payment for the patients to be involved. Furthermore, the studies done in these clinics do not include control cases to assess placebo response or control groups to compare results with standard treatment.
Over-regulation or protection against charlatans?
With advertising claims being made that stem cell therapy rejuvenates aging body parts, with many people suffering from painful joints and other ravages of life, and with the FDA restricting stem cell treatment approval to specific blood conditions, what is the interested potential patient to think? That in the last one hundred years we have overreacted to charlatans and are using regulatory agencies to unnecessarily restrict useful medical therapies? Or that the injection of stem cells into the body with the expectation that these cells will reach the correct destination and perform just the repairs needed is a bit like trusting the promises John Brinkley once made about his goat testicle therapy? Desperation may drive some people to try what is easily available (though very expensive), but the safest course at this time is to stick to FDA sponsored stem cell studies for any attempted treatment. And to remember that placebo effect of any medical treatment, even antibiotics, accounts for 30% or more of the positive responses in studies of efficacy. Glowing reports from friends and relatives don’t necessarily mean that demonstrable changes occurred in their bodies. Research on stem cell treatments continues, but there is still a very long way to go.