TB-500
The ‘healing’ half of the Wolverine stack — and a textbook case of the data-count trap.
Evidence tier: C (large basic-science literature on the natural protein; essentially no human efficacy/safety trials of injected TB-500) · Regulatory status in Canada: not approved; grey-market "research chemical" · Community risk profile: high — unverified sourcing, self-injection, pro-angiogenic concern, and a misleading sense that it's well-studied.
C
Regulatory Update — July 2026
On July 23–24, 2026, an FDA advisory panel (the Pharmacy Compounding Advisory Committee) voted to recommend [KPV / TB-500 / BPC-157] for the 503A Bulk Drug Substances List — the list that lets U.S. compounding pharmacies legally prepare a substance against a prescription. The vote overruled the FDA's own career scientists, who had recommended against all seven peptides reviewed. This is an advisory recommendation, not a final rule: formal rulemaking, including a public comment period, is still required, and legally compounded product is not expected to reach pharmacies for at least 12 months. It does not change this compound's regulatory status in Canada.
Source: FDA Pharmacy Compounding Advisory Committee meeting, July 23–24, 2026, Docket FDA-2025-N-6895.
What it is
TB-500 is a synthetic peptide based on a fragment of thymosin beta-4, a naturally occurring protein involved in cell migration and tissue repair. It's marketed for healing and recovery and is the usual partner to BPC-157 in the "Wolverine" injury-recovery stack.
What People Use it For
Community: tendon/muscle/ligament recovery, wound healing, "systemic repair" — usually injected, often alongside BPC-157.
Form: grey-market lyophilized powder, or a component of premixed blends.
What The Evidence Shows
The literature looks big — and mostly isn't about this. A database search on "thymosin beta-4" returns a large number of papers, but the overwhelming majority study the endogenous protein's basic biology (cell biology, animal models), not the injected grey-market TB-500 product. The count creates a false impression of a well-studied therapy.
Human trials of injected TB-500 for recovery are essentially absent. There is no robust human efficacy or safety dataset for the way the community uses it.
So the honest read is Tier C: biologically plausible, extensively studied as a natural protein, but not shown to work — or to be safe — as a self-injected recovery drug.
Why the human data is thin (and what it doesn't mean): as with BPC-157, no approval pathway means no one funded the human trials. Thin data reflects who paid for research, not proof of no effect — but "the protein it's based on is well-studied" is not "the injectable is proven."
Regulatory Status - Canada
Not approved by Health Canada. Sold as a "research chemical / not for human use" — a seller's legal shield, not a safety statement. TB-500 (thymosin beta-4) is also WADA-prohibited, relevant for any competitive athlete. (US context: TB-500/thymosin beta-4 is among the peptides under FDA compounding-committee review July 23-24, 2026 — a US 503A question that does not change Health Canada status.)
Risks & Red Flags
Human safety largely uncharacterized — with no completed human trials, there's no robust adverse-event dataset either way. Absence of reported harm is not evidence of safety.
Pro-angiogenic concern: like BPC-157, TB-500 is discussed as promoting blood-vessel growth — a theoretical flag for anyone with cancer risk that community messaging rarely raises. Vessels formed don't un-form when the peptide clears (see rescue-gap page).
Injection/sourcing-linked: non-sterile self-injection, unknown real dose, unverified identity.
Sourcing red flags
Unapproved, unverified product: identity, purity, and dose unconfirmed.
"99% purity" ≠ potency (see glossary).
Premixed blends are worse — in a Wolverine/GLOW/KLOW vial you can't confirm the TB-500 dose or attribute effects/reactions (see stacks pages).
DIY reconstitution: the mg↔mcg↔units↔mL error chain applies (see reconstitution page), plus sterility risk.
The Honest Bottom Line
TB-500 looks better-studied than it is. Search its parent molecule (thymosin β4) and you'll find over a thousand papers — but almost all are basic biology of the natural protein, not trials of the synthetic "TB-500" fragment people inject. Strip out the endogenous-biology papers and the human evidence for the injected product is close to nothing.
That's the trap: a big citation count read as a big evidence base. For the compound as actually used — a gray-market injectable in the Wolverine stack — there are no adequate human trials, no approved product, and the same mislabeling risk as every peptide in that supply. Tier C: loud claims, thin human data.
How To Lower Your Risk
Read the evidence tier honestly: a large "thymosin beta-4" literature is not the same as evidence that injected TB-500 works or is safe.
Single compound over premixed blend if using — dose knowable, reactions attributable.
Third-party identity + quantity testing (not a vendor purity claim) is the minimum sourcing bar.
Sterile technique; never share vials.
Talk to a clinician (see clinician page), especially with any cancer history (angiogenesis concern), and consider whether the injury needs assessment rather than a peptide (see delayed-care page).
Sources
Basic-science literature: extensive on endogenous thymosin beta-4 biology; does not establish injected-TB-500 human efficacy, dose, or safety.
Human trials of injected TB-500 for recovery: none identified with posted efficacy/safety results.
WADA-prohibited; under US FDA compounding-committee review (2026), which does not change Canadian status.
Substrate is an independent educational harm-reduction resource. It is not medical, legal, or regulatory advice, and it is not a substitute for a licensed clinician. Compounds discussed are largely unapproved in Canada; nothing here endorses their use. Confirm anything health-related with a qualified professional. Built by a medical-sciences student — not a seller and not a clinic.