Peptides are everywhere, so much so that wellness spas, massage parlours, chiropractor offices and rehabilitation clinics, particularly in the US but also in countries like the UK, are offering peptide injections.
Proponents claim peptides can help combat ageing, heal injuries, dampen inflammation, accelerate weight loss and treat a seemingly endless list of conditions, from osteoporosis to opioid withdrawal. There is little robust evidence to back up these claims, but that hasn鈥檛 stemmed people鈥檚 penchant for peptides. Estimates suggest the unregulated market for peptides is a to industry.
鈥淏ecause there鈥檚 no regulation, it鈥檚 like a free-for-all,鈥� says at the University of Southern California. 鈥淚t鈥檚 like the Wild West right now.鈥� That was part of the impetus behind what I found to be a shocking decision by an advisory committee to the US Food and Drug Administration (FDA). In a series of close votes, it recommended the agency lift regulations on several experimental peptides. Doing so would allow select pharmacies to manufacture the compounds and permit doctors to prescribe them.
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On the one hand, this mitigates the risks associated with buying these products on the unregulated market. On the other, it sends the unfounded message that these compounds have been demonstrated to be safe and effective.
鈥淲hat this announcement did, if anything, was increase the visibility of the peptide world,鈥� says at the University of Southern California.
Once relegated to the fringes of the wellness movement, peptides now seem to be here to stay 鈥� and could cause unintended harm if they aren鈥檛 rigorously tested and regulated.
The origin of peptides
So how did we get here? Interest in peptides dates to the 1920s, when insulin became the first commercial peptide drug. Identifying and characterising peptides was a challenge, however, because of their small size. Most researchers define them as having fewer than 100 amino acids 鈥� the building blocks of proteins 鈥� whereas the FDA classifies them as having no more than 40. Compare that with the average human protein, which consists of 400 to 500 amino acids.
Detecting and analysing peptides became much easier thanks to technological advances such as improved genetic sequencing. This opened a new biological frontier, says Lee. Nearly mentioning peptides have been published since 2000 鈥� double the number seen in the 20th century. In the past decade alone, the FDA has approved than for therapeutic use, one of which, semaglutide, has proven revolutionary. It is the main ingredient in medications like Ozempic and Wegovy, which have transformed the treatment of obesity and type 2 diabetes. 鈥淸They] were a big step in the peptide space,鈥� says Weber. They also propelled peptides into the mainstream.
Online retailers now ship them directly to doors across the US, UK, Canada and European Union, among other places. But most of these peptides aren鈥檛 approved drugs 鈥� they are experimental compounds meant only for research purposes, says Weber. This puts them in a regulatory grey zone. Because the FDA hasn鈥檛 yet deemed the compounds safe and effective, doctors can鈥檛 prescribe them as medications. Yet they can still be bought and sold legally, so long as the supplier doesn鈥檛 make any health claims about them. It is a situation comparable to vitamins and supplements. Similar grey areas exist for peptides in the UK and EU.
One of the glaring drawbacks of this set-up is the risk of contamination. 鈥淲hen substances aren鈥檛 regulated by the FDA, those companies could put, either knowingly or unknowingly, whatever they want into that bottle,鈥� says Weber. A article published in April found that some peptides purchased through one online retailer contained lead, signs of bacterial contamination or a significantly smaller dose than advertised.
This is probably one of the justifications for the FDA advisory committee鈥檚 decision. It recommended the agency add six experimental peptides 鈥� BPC-157, KPV, TB-500, MOTs-C, Semax and epitalon 鈥� to its compounding list, rejecting only one, emideltide. Unlike most medications, compounded products are made to order at select pharmacies, usually due to drug shortages or allergies.
The recommendations passed on slim majorities. The week before the meeting, the US Department of Health and Human Services (HHS), which oversees the FDA, nominated eight new committee members, six of whom had ties to the peptide industry. 鈥淎ll committee members underwent the same ethics review and vetting process required of all FDA advisory committee members,鈥� an HHS spokesperson told Reuters.
If the FDA accepts the committee鈥檚 recommendation, it would allow select pharmacies 鈥� which adhere to standards around product integrity, safety and purity 鈥� to manufacture the compounds. This would bring these six peptides under some regulatory purview. 鈥淲e do not protect the patient by pushing them into the dark,鈥� said committee member Haleem Mohammed 鈥� chief medical officer at Gameday Men鈥檚 Health, which offers peptides 鈥� during the meeting.
However, such a move would also lend each of these peptides an air of credibility. 鈥淐onsumers will assume it is safe and effective,鈥� says Weber, even though that hasn鈥檛 been established in clinical research.
No human trials
In fact, none of these peptides has been tested in a scientifically rigorous way, with clinical trials involving a large number of participants, a control group and clear methods for evaluating efficacy. 鈥淭here are no clinical trials, no clinical studies on the efficacy and safety of their use in humans,鈥� says Weber. 鈥淧eriod. Full stop. End of story.鈥�
Instead, most research comes from animal studies. For instance, Lee and his colleagues have found that MOTs-C, a peptide released naturally during exercise, can help in mice. It can also in the animals. They are now evaluating whether it could delay age-related conditions, including 础濒锄丑别颈尘别谤鈥檚, heart disease and cancer. But these studies are a far cry from the rigorous trials needed to determine its efficacy in humans.
There is also the question of side effects. TB-500 seems to accelerate tissue regeneration, . But Weber says this ability may also spur cancer growth 鈥� a risk that has yet to be evaluated, even in animals.
It also isn鈥檛 clear how these peptides should be administered. 鈥淲hat strength should you use? What frequency? How long do you cycle on and off? None of these things have been elucidated as to what is most effective,鈥� says Weber.
It is possible that easing manufacturing restrictions on these peptides could accelerate research into their effects. But in the meantime, people will be treating themselves as guinea pigs.
The FDA compiled research on all seven peptides for the committee to . Briefs for each peptide conclude that there isn鈥檛 sufficient evidence to support them being added to the compounding list. Although the committee disagrees, the decision ultimately rests with the FDA. 鈥淲hatever the outcome is, one thing is for sure: research really needs to accelerate on all these peptides,鈥� says Lee.
