I’ve written extensively, though not lately, about veterinary stem-cell therapies (1, 2, 3, 4, 5). These are treatments in which stem cells are injected into an animal to treat some disease. The most common current use is to inject stem cells extracted from a patient’s own fat in order to treat arthritis or other orthopedic problems.
The basic science research so far suggests these might turn out to be useful therapies for some conditions. There is, however, very little real-world clinical research to support using them. In humans, these therapies are not legal outside of special circumstances, typically research studies, because even most proponents of these therapies do not believe they have yet been adequately studied to justify widespread routine use. The evidence in dogs in cats is extremely sparse. So while I consider this a promising therapy worth studying, it is essentially experimental and unproven and so should be reserved for situations in which all better-understood options have been exhausted.
Veterinarians are frequently able to make use of therapies not permitted for human use for a variety of political and legal reasons. Technically, most therapies for pets are regulated in the same way as therapies for humans, and most should be subject to appropriate scientific testing and licensing before clinical use. However, the regulatory agencies (primarily the FDA and the USDA) recognize that evidence will always lag behind in veterinary medicine compared to human medicine, due to the lower priority and fewer available resources for studying potential therapies. Uncompromising, strict adherence to all regulations would leave few therapies available to vets. There is also little political will to support stricter enforcement given the general waning of confidence in government regulation in recent decades. So veterinarians are often able to provide therapies that are technically illegal with an understanding that these agencies will not enforce the rules in most cases.
While there are some good pragmatic reasons for this situation, it is often forgotten that the regulations exist for a purpose. Prior to the age of vigorous government oversight of medicine, people were routinely harmed and even killed by unsafe and ineffective medical and cosmetic products. This is why the FDA was created in the first place. Without enforceable requirements for appropriate scientific testing, such products tend to be marketed and used well beyond anything justified by available evidence. Not having been rigorously tested, they may well be ineffective or even harmful. This may be a chance worth taking under the circumstances, but we shouldn’t kid ourselves that this risk isn’t present.
The FDA is continuing this tradition with a recent draft statement on the regulation of stem-cell therapies in veterinary medicine. The statement does a number of useful things, including asserting the agency’s authority to regulate these products and establishing legal definitions related to the various kinds of therapies involved. However, the agency also inserts a little statement which suggests that since therapies applied strictly to pets rarely have a direct impact on human health or food safety, they don’t really intend to enforce any regulation of these products:
Autologous Type II (ATII) ASCPs for Non-Food Producing Animals
Although ATII ASCPs require an approved NADA, conditional approval or index listing to be legally marketed, FDA recognizes that these products pose a lower risk to human and animal safety than other categories of ASCPs when used in non-food producing animals and are, therefore, a lower enforcement priority.
While I recognize that rigid enforcement of regulations to the standard of human medicine would restrict the availability of therapies for companion animal use, there ought to be a middle ground between full enforcement and essentially no enforcement at all. Several companies currently profit from stem cell therapies aggressively marketed to vets and the public without much evidence of safety and efficacy. There is a reason such therapies cannot be legally marketed for human use. The uncertainty in the lack of data represents some real risks.
To their credit, some of these companies have conducted some clinical research on their products, though this is likely as much for the value of such studies in marketing to veterinarians as for the protection of patients. And as I’ve often said, there is definitely good reason to be hopeful some of these therapies will turn out to be truly beneficial. But nothing is without a downside, and so far the data isn’t there for us to confidently determine the risks and benefits of these products. It is encouraging that the FDA is recognizing a need to assert some regulatory oversight in this area, it will not help to protect the public or our pets from potentially ineffective or harmful therapies if no actual oversight is implemented.
Public comment on this statement will be accepted until September 30, 2014 at: regulations.gov (search for the docket number FDA-2014-D-0634). I have posted the following comment, and I encourage anyone interested in this subject to comment as well:
As a veterinarian concerned about the safety and efficacy of the treatments I employ, I support the FDA asserting regulatory authority in this area and establishing appropriate guidelines and definitions. However, despite the lack of direct risk to human health and food safety in the use of stem-cell therapies in non-food animals, a failure to enforce the requirements for pre-market testing and approval for these products leaves the public and their animals vulnerable to unproven claims of safety and efficacy as well as unforeseen health risks. These therapies are not permitted in humans without appropriate regulatory approval because it is understood that the absence of such evidence of safety and efficacy places patients at risk. The same is true for non-human animal patients.
In addition to protecting public health, premarket testing regulations are an important form of protection for the consumer of medical products. The marketing of stem-cell therapies in veterinary medicine frequently implies or directly makes claims of safety and efficacy not yet proven by appropriate research evidence.
While strict enforcement of pre-market testing to the standard for human medical products is not feasible and would restrict too severely access to potentially beneficial veterinary therapies, I believe some level of oversight is still called for. I encourage the FDA to amend this statement to allow for some flexibility in format and timeframe but to still require some form of NDA trials and licensing for these products.