An FDA panel is backing 6 unproven peptides, but their efficacy and safety are questionable — here’s what experts warn you to consider before ordering

The “Wolverine stack” is a nickname given to a peptide combination of BPC-157 and TB-500, which is supposed to accelerate healing, akin to the abilities of the Marvel character after whom it’s named.

“It leaves me speechless,” Jodi Segal, a professor at Johns Hopkins School of Medicine, told Moneywise. “I don’t know why people would think this is a good idea to inject these unknown substances without proven efficacy or safety.”

Thus far, unregulated peptide users have been forced to get their doses through back-alley channels, from overseas retailers or via online storefronts known as the gray market. However, the FDA has taken steps toward easing restrictions on six peptides, skirting around the traditional, science-based process of FDA approval.

Unproven peptides could sidestep FDA approval for commercial distribution

On July 23 and 24, an FDA advisory committee convened to discuss whether seven popular peptides should be included on the 503A bulks list, a list of drug substances that compounding pharmacies are allowed to dispense even if they don’t have FDA approval. The panel of outside advisers narrowly voted to recommend six of the seven proposed peptides.

The peptides they recommended were BPC-157, Epitalon, KPV, MOTS-c, Semax, and TB-500. You may recognize BPC-157 and TB-500 from the aforementioned Wolverine stack, but proponents claim that these peptides have a wide range of benefits. For example, Semax is a peptide that is supposed to enhance focus and memory, while MOTS-c allegedly helps users lose weight and appear younger.

Importantly, this action is distinct from FDA approval, which entails a series of clinical trials that must prove that a medicine is safe and effective. If the FDA allows these peptides to be distributed by compounding pharmacies, they won’t have to go through any such tests before Americans can get access to them legally.

Eunjoo Pacifici, Chair and Associate Professor of Regulatory and Quality Sciences at the University of Southern California’s School of Pharmacy, notes that this is not the purpose of compounding pharmacies, which exist to meet unmet medical needs. For example, if a drug doesn’t have a liquid formulation, a patient who cannot swallow pills would go to a compounding pharmacist to get the medicine crushed and put into liquid form.

“Allowing compounding of these peptides, to me, begs the question: What is the unmet medical need?” Pacifici told Moneywise. “What is the public’s demand based on? It’s not really based on an unmet medical need. It’s not based on sound clinical science.”

Proponents of the decision claim that many Americans are already using peptides, and they’re buying them through gray markets, which may introduce contaminants to these doses, which are usually administered by injection. However, the panel included more than a half-dozen panelists who run businesses or pharmacies that specialize in peptides.

The global peptide market is quite valuable, worth $140.9 billion in 2025 and projected to grow to $164 billion in 2026, according to Grand View Research. Healthcare investment bank Leerink Partners estimates that there is a $2.2 billion telehealth market for the six peptides in question.

“Serious conflicts of interest erode the integrity of decisionmaking at the FDA and undermine confidence in the idea that the FDA can make fair and independent determinations on core issues of safety and effectiveness,” Joshua Shafstein, former Principal Deputy Commissioner of the FDA, told Moneywise in an email.

No official decision has been made regarding these six peptides. The FDA itself still needs to sign off on them.

Are peptides safe?

There are plenty of safe, FDA-approved peptide-based treatments that have gone through the years-long clinical trials necessary to determine if they’re safe and effective. Ozempic spent nearly a decade in clinical trials before it was approved for treating type 2 diabetes in December 2017.

However, as for the six peptides backed by the FDA advisory committee, we don’t know if they’re safe. For the most part, we don’t even know if they work. There have been several preclinical studies done, some of which show potential. However, many of these studies were conducted on animals or human cells in a lab environment, which doesn’t necessarily mean they’re effective in humans.

“We have cured so many animal diseases that we have artificially created through animal models that never translate to human conditions,” Pacifici says. “They fail because the hypothesis did not pan out, but that is good science. The result is negative, and that is fine.”