As the field of regenerative medicine has advanced in recent years, athletes have increasingly turned to therapies that utilize biological substances, such as stem cells, to heal sports injuries faster.
Researchers are still investigating the use of biological treatments, and their potential efficacy, but given the complicated and rapidly evolving nature of regenerative medicine, the questions below have been compiled to address some of the most important information that athletes need to know about orthobiologics, including stem cell therapies.
What does the term orthobiologics mean?
Most commonly associated with sports injuries, orthobiologics are biological substances, such as platelet-rich plasma (PRP) or stem cells, used to speed the healing process for musculoskeletal injuries. They may be used alone or in combination with conventional pharmaceutical and non-pharmaceutical based treatment. More specifically, orthobiologic therapies introduce high concentrations of naturally occurring cellular concentrates to an injury with the intention of expediting the healing of muscles, ligaments, tendons, and bones; thereby shortening recovery time and decreasing injury-related inflammation and pain.
In sports medicine, orthobiologic treatments are used to treat both acute and chronic conditions, including common conditions caused by overuse. Athletes and orthopedists often turn to orthobiologic therapies in the hope of returning an athlete to preinjury physical condition as soon as possible. For the most part, orthopedists will use biologics in place of pharmaceuticals and/or invasive surgery.
How do stem cell therapies work to accelerate healing?
Over the years, clinicians have placed a lot of hope in the healing capabilities of stem cells due to their unique potential to become different types of tissues as needed, such as cartilage or bone. In theory, the presence of the stem cells at the site of injury could assist in healing because the stem cells are able to “turn into” the tissue that is injured and needs to be healed. Stem cell treatments can involve harvesting stem cells from the patient, and then re-injecting them directly into the injured site or the purchase of commercial preparations or donated stem cells.
Where do the stem cells come from?
For stem cell therapies that involve injecting the patient’s own stem cells, doctors can obtain these from the patient’s skin, bone, fat, or other tissues depending on the treatment plan. Clinicians may also purchase donated stem cells that are derived from amniotic fluid, umbilical cord-blood, bone, or other sources. Also available commercially are various collagen or chorion tissue platforms that are embedded with stem cells, which are showing promise for treating skin wounds of diabetic patients or burn victims.
In addition, there are other stem-cell preparation techniques currently undergoing experimentation. In fact, some clinics develop their own proprietary way of harvesting and using stem cells to treat various wounds. The source of stem cells, and how they are used, can vary widely between clinics. Some clinics “boost” the stem cell preparation with additional growth factors or hormones hoping that this will increase the healing capabilities of the treatment.
Any athlete considering stem cell treatments should get a detailed description of the treatment plan, including the source of the stem cells, and the use of any other growth factors or hormones.
Does the WADA Prohibited List prohibit stem cell treatments?
In most cases, stem cell therapy is allowed if no prohibited substances are added to the material and the stem cells are locally applied only to the injury with no intent to enhance performance. The sole outcome of stem cell therapy should be the return to pre-injury level of function, or a normal state of health.
As such, stem cell injections are prohibited if the product is modified in a way that can offer performance-enhancing benefits. WADA further clarifies that it’s prohibited to use both normal and genetically modified cells in any way if the process causes performance enhancement. Based on these regulations, athletes should be aware that the use of stem cell products cannot justify a positive doping test if any prohibited substances are identified in a sample.
Is a TUE required for Stem Cell Therapy?
You do not need a TUE for stem cell therapy as long as all of the following are true:
- You are donating and then receiving your own stem cells and no other growth factors, hormones, or other prohibited substances will be added to the preparation. Or, for commercial stem cell preparations, there are no growth factors or other hormones contained within.
- The stem cell preparation will be injected directly into the injured site, and there is no reason to expect that it will enter the circulatory system in meaningful quantities (e.g. the stem cells stay local to the site, and the administration of the stem cells will not ultimately be systemic).
- The stem cell preparation is a small volume (1-3 mL maximum).
- There are no intravenous infusions or drips of in excess of 100mL per 12-hour period required during the clinical visit.
- The expected outcome of the treatment is that the tissue will return to its normal strength and function or below.
If there is any chance or expectation that the stem cell therapy will make a tissue perform beyond the normal state (bigger, better, faster, stronger) than it was prior to the injury, or if the plan is to augment strength or ability of otherwise normal tissue through the use of stem cells, then this is a prohibited use of stem cells and requires a Therapeutic Use Exemption in advance.
When considering stem cell therapy, athletes should also discuss these guidelines with their physician and contact Athlete Express at (866) 601-2632, or our Drug Reference team at drugreference@USADA.org, with any questions.