BPC-157 vs TB-500: what each is, what's been studied, and FDA status

Quick answer BPC-157 and TB-500 are two unrelated lab-made peptides that get talked about as a pair, and neither has much human research behind it. In July 2026 an FDA advisory committee reviewed both, and news reports say it recommended adding each to the list of ingredients pharmacies may compound, against the advice of FDA's own staff. Today their position is the same: neither is FDA-approved or on that list, so licensed pharmacies can't compound either one. What to watch for is a proposed rule from FDA, and there was none as of October 2026.

How do BPC-157 and TB-500 compare?

What the research measured

Neither peptide has much human research, and the human trials people cite for TB-500 are of a different molecule.

• Most BPC-157 research is preclinical: a 2025 systematic review included 36 studies, and 35 of them were preclinical.
• The human reports on BPC-157 are two small, uncontrolled studies from private clinics in Florida.
• FDA's reviewers found no study in which TB-500 was given to people; small human trials exist only for full-length thymosin beta-4.

BPC-157. The name stands for "body protection compound." A review by the Zagreb group that first made it summarizes their own work, mostly in rats (Sikiric and colleagues, 2011). Independent reviewers noted that the large majority of studies used small rodent models, that only a handful of research groups have studied it in depth, and that its effects remain to be confirmed in people (Gwyer and colleagues, 2019). The 2025 review screened 544 articles, included 36, and found no clinical safety data (Vasireddi and colleagues, 2025).

The two human reports are small. One was a retrospective chart review at a single clinic: of 17 patients who had received knee injections, 16 were reached by phone and asked to rate their own pain, and four of them had also received thymosin beta-4 (Lee and Padgett, 2021). The other followed two adults over three days to look at safety (Lee and Burgess, 2025). Two people over three days cannot show that a substance is safe.

TB-500. Its structure was reported by analytical chemists working on doping control (Esposito and colleagues, 2012), and most peer-reviewed work on the fragment is chemistry of that kind. The full thymosin beta-4 protein has been tested in people, for example as eye drops in a small phase 2 trial of nine people with severe dry eye (Sosne and colleagues, 2015). FDA's reviewers say the protein and the fragment are not the same substance. More on TB-500 is here.

The two together. A 2026 scoping review of six popular peptides found that about two thirds of the publications used animal models and that the few human studies mostly lacked rigorous designs (Tewari and colleagues, 2026). The only study of the pairing found in a PubMed search on October 6, 2026 was in 32 rats; its authors called it exploratory (Biçer and colleagues, 2026).

Full citations are in the Sources list below.

The "Wolverine stack": what the term means

"Wolverine stack" is an online nickname for using BPC-157 and TB-500 together. The name comes from Wolverine, a comic-book character. It is slang, not a medical or regulatory term, and a PubMed search for it returns nothing.

The nickname doesn't change the facts. Licensed pharmacies can't compound either peptide, alone or together, because neither is on the 503A bulks list. FDA's safety statements, quoted in full below, say it lacks the information to know whether either would cause harm in people. No clinical trial of the pairing in people turned up in that search. This page gives no amounts or schedule for either, and doesn't recommend the pairing.

Why are both unavailable?

Neither BPC-157 nor TB-500 is an FDA-approved drug or on FDA's 503A bulks list, so licensed pharmacies can't compound either one; FDA removed both from its interim Category 2 on April 22, 2026 after the nominators withdrew their nominations, which FDA says is not a determination about either substance (how the categories work). In July 2026 FDA's reviewers proposed against adding either to the list, news reports (CNN, July 31, 2026) say the advisory committee voted to recommend both anyway, and only a final rule after notice-and-comment rulemaking would change that, with no proposed rule published as of October 6, 2026 (the full status is here).

Is this right for me?

Not today, through any licensed route. No licensed pharmacy can prepare either peptide, so no provider can prescribe one through a pharmacy.

The honest options:

• Use the sign-up at the end of this page if you want availability news. It reserves nothing.
• Bring what's behind the question to your own doctor, who can go over approved treatments.
• Steer clear of "research use only" products; the risks are under Safety information.
• If you compete in tested sport, FDA's briefings note that both appear on the World Anti-Doping Agency's prohibited list.

Should FDA's rules change, a licensed provider in your state would still review your health history and decide, and the answer may be no.

How it works

1. Enter your email below. The form at the end of this page asks for your email address and state, and nothing about your health.
2. Hear from us only if it becomes available through a licensed provider. We write about availability and nothing else, and you can unsubscribe anytime.
3. A licensed provider still decides. Being on the list is not a reservation or a prescription. If FDA's rules change, a provider licensed in your state reviews your health history first and can decline.

FAQ

Are BPC-157 and TB-500 the same thing? No. They are unrelated peptides of different sizes, from different research traditions.

Is either one FDA-approved? No. Neither is an FDA-approved drug, and neither is on the 503A bulks list.

Can a licensed pharmacy combine them? Licensed pharmacies can't compound either one today, alone or together. What would be allowed after a final rule depends on the rule FDA writes.

Is the "Wolverine stack" legal? The nickname changes nothing. Neither peptide can be compounded by a licensed pharmacy, and neither is FDA-approved.

What this means for you

As of October 2026, licensed pharmacies can't legally compound BPC-157 or TB-500 for patients: none is on FDA's 503A bulks list, and only FDA rulemaking changes that. If FDA lists them one day, the legal route would be a prescription from a licensed provider in your state, filled by a licensed pharmacy; compounded medications are not FDA-approved. Until then, products sold online as "research use only" aren't made for people.

The July 2026 FDA peptide vote, explained covers all seven peptides the committee reviewed and what has to happen next.

Safety information

There is no FDA-approved, labeled product of either peptide to describe. FDA's safety-risks page says, word for word:

• On BPC-157: "Compounded drugs containing BPC-157 may pose risk for immunogenicity for certain routes of administration and may have complexities with regard to peptide-related impurities and active pharmaceutical ingredient (API) characterization. FDA has identified no, or only limited, safety-related information for the proposed routes of administration. Therefore, the agency lacks sufficient information to know whether the drug would cause harm when administered to humans."
• On TB-500: "Compounded drugs containing thymosin Beta-4, Fragment (LKKTETQ) may pose risk for immunogenicity for certain routes of administration due to the potential for aggregation as well as peptide-related impurities. FDA has not identified any human exposure data [sic] drug products containing Thymosin Beta-4, Fragment. FDA lacks important information regarding any safety issues raised by this drug, including whether it would cause harm if administered to humans."

Immunogenicity means the risk of an immune reaction. FDA's briefings add that neither substance is well characterized, and that inconsistent naming means a patient could receive a different substance than intended.

Products sold as "research use only" are not prepared by a licensed pharmacy for a named patient, no prescriber reviews your history, and nothing assures you of their identity, purity or sterility. Everlon never sells "research use only" products. Compounded medications are not FDA-approved, which would remain true even if a pharmacy could one day prepare either peptide.

If you have used a product sold under either name and something feels wrong, stop and contact a doctor; you can also report it to FDA's MedWatch program. If this is a medical emergency, call 911.

Sources

• Sikiric P, Seiwerth S, Rucman R, et al. Stable gastric pentadecapeptide BPC 157: novel therapy in gastrointestinal tract. Current Pharmaceutical Design. 2011;17(16):1612-32. PMID: 21548867. PubMed, accessed 2026-10-06
• Gwyer D, Wragg NM, Wilson SL. Gastric pentadecapeptide body protection compound BPC 157 and its role in accelerating musculoskeletal soft tissue healing. Cell and Tissue Research. 2019;377(2):153-159. PMID: 30915550. PubMed, accessed 2026-10-06
• Vasireddi N, Hahamyan H, Salata MJ, et al. Emerging Use of BPC-157 in Orthopaedic Sports Medicine: A Systematic Review. HSS Journal. 2025;21(4):485-495. PMID: 40756949. PubMed, accessed 2026-10-06
• Lee E, Padgett B. Intra-Articular Injection of BPC 157 for Multiple Types of Knee Pain. Alternative Therapies in Health and Medicine. 2021;27(4):8-13. PMID: 34324435. PubMed, accessed 2026-10-06
• Lee E, Burgess K. Safety of Intravenous Infusion of BPC157 in Humans: A Pilot Study. Alternative Therapies in Health and Medicine. 2025;31(5):20-24. PMID: 40131143. PubMed, accessed 2026-10-06
• Esposito S, Deventer K, Goeman J, Van der Eycken J, Van Eenoo P. Synthesis and characterization of the N-terminal acetylated 17-23 fragment of thymosin beta 4 identified in TB-500, a product suspected to possess doping potential. Drug Testing and Analysis. 2012;4(9):733-8. PMID: 22962027. PubMed, accessed 2026-10-06
• Sosne G, Dunn SP, Kim C. Thymosin β4 significantly improves signs and symptoms of severe dry eye in a phase 2 randomized trial. Cornea. 2015;34(5):491-6. PMID: 25826322. PubMed, accessed 2026-10-06
• Tewari K, Liu TP, Im C, et al. Peptide Supplements and Their Therapeutic Applications in Sports Medicine. American Journal of Sports Medicine. 2026 (online ahead of print, August 11). PMID: 42578445. PubMed, accessed 2026-10-06 (abstract only)
• Biçer O, Adanir O, Güleryüz Y, et al. Effects of BPC-157 and TB-500 on Achilles tendon healing in rats: A histopathological and biomechanical study. Joint Diseases and Related Surgery. 2026;37(3):822-837. PMID: 42542926. PubMed, accessed 2026-10-06 (abstract only)
• FDA. FDA Briefing Document: BPC-157 (free base) and BPC-157 acetate. Pharmacy Compounding Advisory Committee, July 23-24, 2026. fda.gov, accessed 2026-10-06
• FDA. FDA Briefing Document: TB-500-related bulk drug substances. Pharmacy Compounding Advisory Committee, July 23-24, 2026. fda.gov, accessed 2026-10-06
• FDA. Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks (content current as of 04/22/2026). fda.gov, accessed 2026-10-06
• FDA. Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the FD&C Act (interim categories list). Updated May 14, 2026. fda.gov, accessed 2026-10-06
• FDA. Guidance for industry: Interim Policy on Compounding Using Bulk Drug Substances Under Section 503A of the FD&C Act (January 2025). fda.gov, accessed 2026-10-06
• CNN. FDA advisers support easing restrictions on six peptides. Here's what those drugs are and what happens next. July 31, 2026 (news report). cnn.com, accessed 2026-10-06