Preloaded Autoinjector | Wolverine Stack (BPC-157 + TB-500) | 3ml Pen | 20mg

The wolverine stack pen is a preloaded 3ml research device holding BPC-157 and TB-500 together in solution at 6.67mg/ml combined, giving 20mg in total. Two peptides in one reservoir raises a question no single-compound device does: their optimal conditions differ, no compatibility data exist, and one of the two has never had its molecular identity fixed.

Specification Table

What Changes When Two Peptides Share One Cartridge?

The degradation chemistry of each component is reasonably well understood alone. What has never been measured is what they do to each other, and the two do not want the same conditions.

BPC-157 is the simpler half. GEPPPGKPADDAGLV contains no cysteine, methionine, tryptophan, tyrosine, histidine, asparagine or glutamine, which removes oxidation and deamidation entirely, and that absence is why it survives human gastric juice at pH 1 to 2 with pepsin, a property Sikiric’s group documented and Mateescu and colleagues restated in 2026. The one real vulnerability is the Asp10-Asp11 pair, where succinimide formation leads to isoAsp and, at low pH, to Asp-X chain cleavage; Mateescu and colleagues name that junction as the primary chemical degradation risk. The peptide is unstructured and hydrophilic, carries about minus 2 charge at pH 7 with a calculated isoelectric point of 3.7 to 4.2, and has no reported aggregation. Gastric stability says nothing about months in a buffered cartridge.

The second component depends on which molecule it is. If the device holds full-length thymosin beta-4, the 43-residue protein carries Met6, which oxidises to the sulfoxide. That reaction does more than dent an assay figure: Huff and colleagues reported in 1995 that the sulfoxide binds actin with reduced affinity, and Young and colleagues reported in 1999 that it is itself a distinct anti-inflammatory species produced by monocytes under glucocorticoid exposure. Asn26-Pro27 is the only deamidation site and it is slow. If instead the device holds the acetylated heptapeptide Ac-LKKTETQ, the picture changes: the acetylated N-terminus rules out pyroglutamate and diketopiperazine routes, the C-terminal glutamine deamidates slowly, the Thr-X bonds are acid-labile, and there is no methionine at all.

Putting the two in one solution forces a compromise. pH 4 to 6 minimises aspartate isomerisation in BPC-157 and suits thymosin beta-4 reasonably, so that window is the sensible target, but no stability study has confirmed it for the mixture. Methionine oxidation is oxygen-driven, which makes headspace and the number of reservoir entries a real variable for one component and irrelevant for the other. No compatibility data, co-formulation assay or adsorption measurement exists for this pairing.

Which TB-500 Is in the Cartridge?

The name TB-500 has never been anchored to a single molecule, and the candidates differ by a factor of 5.6 in molecular weight, which propagates into every molar calculation on this page.

Candidate one is full-length thymosin beta-4: Ac-SDKPDMAEIEKFDKSKLKKTETQEKNPLPSKETIEQEKQAGES, 43 residues, CAS 77591-33-4, average mass 4963.5, with nine lysines and eleven acidic residues and no cysteine, tryptophan or tyrosine. Candidate two is the N-acetylated 17-23 fragment Ac-LKKTETQ, the actin-binding motif, seven residues, average mass 889.02, with no verified CAS number.

What the evidence does say is what was in at least one commercial product. Esposito and colleagues synthesised and characterised the heptapeptide in 2012 precisely because that is what they found in material sold as TB-500, and Ho and colleagues that same year describe TB-500 as a synthetic version of an active region of thymosin beta-4 rather than the protein. FDA’s Federal Register notice listing the substance for compounding evaluation does not define which molecule it means. The single-component TB-500 device page works through the ambiguity. Here the instruction is short: read the mass on the certificate of analysis, because 889 and 4963 are not close.

BPC-157 TB-500 Solution Stability: What Has Been Measured

Nothing, for the mixture. No bpc-157 tb-500 solution stability study, compatibility assessment or validated dual assay has been published.

The gap has a specific consequence for purity claims. A certificate reporting one ultraviolet peak-area percentage for a solution of two peptides differing 3.5-fold in molecular weight is reporting a number without a meaning, since peak area at 214 nm scales with peptide bonds rather than molar quantity. Each component needs separate quantitation against its own reference standard. Mateescu and colleagues note that no pharmaceutical-grade formulation of BPC-157 has ever been validated.

What can be said is which reactions a bpc-157 tb-500 solution stability study would resolve: isoAsp at the Asp10-Asp11 junction, invisible to mass measurement; methionine sulfoxide at plus 16 daltons if the 43-mer is present; deamidation at plus 1; and total recovery for each component separately, since adsorptive loss differs between a 1419 dalton peptide and a 4963 dalton one.

What Does the Wolverine Stack Pen Deliver Per Increment?

Twenty milligrams in 3 ml gives 6.67 mg/ml combined, so each 0.01 ml graduation carries 66.7 micrograms of total peptide and each 0.1 ml carries 667 micrograms; per component that is [SPLIT]/300 mg and [SPLIT]/30 mg.

Molar concentrations need the split and the identity. BPC-157 is ([SPLIT]/3) divided by 1419.5, multiplied by 1000 for millimolar; the second component divides by 4963.5 for the 43-mer or 889.0 for the heptapeptide. At an even 10 plus 10 split that is 3.33 mg/ml of each, giving 2.35 mM BPC-157 and either 0.67 mM or 3.75 mM for the other, with 33.3 micrograms of each per 0.01 ml graduation: 23.5 nanomoles of BPC-157 and 6.7 nanomoles of thymosin beta-4.

Against the literature the device is coarse. Bicer and colleagues used 10 micrograms per kilogram per day of BPC-157 and 60 of TB-500 in rats, which for a 300 gram animal is 3 and 18 micrograms, or 0.001 and 0.005 ml of an evenly split device: both below the smallest graduation the mechanism resolves. The human intravenous pilot gave 10 to 20 mg of BPC-157 once, roughly one to two full cartridges of that component. Any nanomolar concentration in a cell assay is more than a thousandfold below 3.33 mg/ml, and the dilution calculator handles the series faster than paper.

Wolverine Stack Pen vs Vial: What the Format Settles

For a two-component product the wolverine stack pen vs vial question is about ratio control: a vial pair lets the two peptides be combined at the bench, while a preloaded cartridge fixes the proportion at manufacture.

That cuts both ways. A device removes reconstitution and the errors inside it, and guarantees every draw carries the same proportion of both peptides, which matters if the experiment compares the pair against either alone. A 10mg plus 10mg vial pair gives the ratio back as an experimental variable, at the cost of two reconstitutions and two sets of transfer error. Single-compound devices exist for either peptide alone, including the 15-residue peptide on its own, which is the cleaner starting point when the design needs one variable at a time. The generic case for preloaded devices is in the pen and vial comparison, and the range sits on the preloaded autoinjector category page.

Wolverine Stack For Sale: What the Product Record Does Not State

Anyone comparing one wolverine stack for sale listing against another has four fields to ask for, and the split is the one that changes every calculation here.

The split is not stated. The product record gives 20 mg combined, which is why this page carries [SPLIT] mg BPC-157 plus [SPLIT] mg TB-500 rather than two numbers, and without it no molar concentration or per-increment mass can be quoted for either peptide. The identity of the second component is not stated either, and that decides whether a given milligram figure is 0.2 or 1.1 micromoles.

Solution pH is not published on the product record, and since pH 4 to 6 is the window that minimises the aspartate route in BPC-157, the number is worth having. Excipient system: not published on the product record. Confirm against certificate of analysis. Appearance and fill date are also absent from the wolverine stack pen record, and for a solution product the fill date is where every stability question starts.

Verifying a Wolverine Stack Pen and Its Contents

Neither peptide has a chromophore above 220 nm, so absorbance at 280 nm, the ordinary first check on a protein solution, returns nothing useful for either component of a wolverine stack pen.

Quantitation therefore has to be chromatographic and component-specific. Reversed-phase separation at 214 nm resolves two peptides differing this much in size, but converting peak area to mass needs a reference standard for each. Mass spectrometry gives the identity check that matters most: 1419.6 for BPC-157, then either 4963.5 or 889.0 for the second component, which settles the question the label leaves open.

Degradation markers split by component. Methionine sulfoxide adds 16 daltons if the 43-mer is present, deamidation adds 1, and the isoAsp isomer at the Asp10-Asp11 junction has the same mass as the parent, so it needs a separation method or an enzymatic isoaspartate assay. For device metrology, allow the cartridge to reach ambient temperature before actuating, verify delivered mass gravimetrically once, and inspect each draw against a white card for particulate.

What the Literature Reports on the Pairing

One published study has given both peptides to the same animals, and it found that the combination did no better than either peptide alone.

Bicer and colleagues reported in 2026 on 32 male Sprague-Dawley rats with Achilles tendon transection and repair, treated intraperitoneally each day for four weeks with BPC-157 at 10 micrograms per kilogram, TB-500 at 60 micrograms per kilogram, or both. TB-500 alone raised load to failure with a p value below 0.05, and the paper states that combined treatment conferred no additional benefit compared with either agent alone. That is the entire direct evidence for the pairing. Wider context sits in the article on this peptide pairing.

The separate records are thin in different ways. Human exposure to BPC-157 amounts to three uncontrolled pilots totalling fewer than 30 subjects, covering intra-articular knee administration, interstitial cystitis and an intravenous safety study, as summarised by McGuire and colleagues in 2025; phase I trial NCT02637284 was terminated without results. Its pharmacokinetics were not published until He and colleagues reported them in 2022: an intravenous half-life of 15.2 minutes in rats and 5.27 minutes in beagles, intramuscular bioavailability of 14 to 19 percent in rats and 45 to 51 percent in dogs. For thymosin beta-4, Ruff and colleagues ran a randomised placebo-controlled intravenous study in volunteers in 2010, and Sosne and colleagues tested 0.1 percent eye drops in 72 subjects over 28 days: primary endpoints were not met, with a secondary 27 percent reduction in ocular discomfort at p equals 0.0244. No human has received the two peptides together in any published study.

Safety and Regulatory Position

No product containing BPC-157, thymosin beta-4 or the Ac-LKKTETQ heptapeptide is approved by FDA, EMA, PMDA, TGA or Health Canada.

Both components were on the agenda of FDA’s Pharmacy Compounding Advisory Committee on 23 July 2026 for 503A bulk-list evaluation, under Federal Register document 2026-07361 and docket FDA-2025-N-6895, listed as BPC-157 free base or acetate and TB-500 free base or acetate with wound healing as the evaluated use, alongside KPV and MOTS-c. USADA’s advisory, updated 10 August 2026, states that FDA’s briefing document cited inadequate safety and efficacy evidence and that there is no legal basis to include BPC-157 in any compounded medication. A reported 2023 category placement and the committee’s votes were not verified from FDA documents and should be checked against the docket.

On the anti-doping side, USADA describes BPC-157 as prohibited under section S0 for non-approved substances, and the long-standing S2 entry naming thymosin beta-4 and its derivatives covers the other component. Neither peptide is a component of an approved drug, has a USP monograph or sits on the 503A bulks list. No toxicology of the combination exists, and the absence of adverse findings in the human pilots reflects their size rather than a safety result. Supply is for laboratory research, and the device is not offered for administration to a human or an animal.

What Does Each Half of the Wolverine Peptide Stack Claim to Do?

BPC-157 is a synthetic pentadecapeptide, fifteen residues taken from a sequence identified in human gastric juice, and its rodent literature is the largest of any compound in this catalogue. Reported effects cluster around tissue repair after injury: faster closure of transected tendon and of ligament in rats, improved healing of muscle and of the gastrointestinal tract, and protection against damage from non-steroidal anti-inflammatory drugs. Angiogenesis is the mechanism most often proposed, with blood vessel formation into the healing site reported alongside upregulation of VEGF receptor 2 and, in some papers, of the growth hormone receptor in tendon fibroblasts. Migration of fibroblasts into the wound is the other reported step.

TB-500 is the other half and is a different kind of thing. It is a synthetic fragment corresponding to the actin-binding region of thymosin beta-4, not the intact protein, and its proposed action is on actin sequestering and therefore on cell motility. Reported effects overlap with the first: cellular migration, angiogenesis and tissue regeneration in cardiac, corneal and dermal models. The overlap is why the two are stacked, and the page above sets out which molecule is actually likely to be in the cartridge.

The claims that follow from this pairing in marketing go further than either literature. Muscle recovery, cartilage repair, gut health, skin quality, relief from overuse injuries and recovery from ligament injuries all appear in descriptions of the wolverine peptide stack. Each maps onto a rodent model somewhere in the two literatures. None has been tested in a controlled human trial, of either compound alone or of the pairing, and the pairing itself has never been formally studied in any species.

What Is the Evidence Position and the Anti-Doping Position?

The evidence position is easy to state and easy to misread. There is a great deal of published rodent work, most of it from a small number of groups, much of it using injury models with short follow-up and modest sample sizes, and almost none of it independently replicated across laboratories. Reports that these compounds reduce inflammation come from measurements of inflammatory cytokines in tissue rather than from clinical endpoints, and a compound that lowers a cytokine in a rat does not thereby reduce inflammation in a person. Neither compound is FDA approved for anything, and no completed human efficacy trial exists for either. Nothing sold as a research peptide is FDA approved by definition, since approval attaches to a finished drug product rather than to a molecule.

The anti-doping position is unambiguous and worth knowing before a purchase. The World Anti-Doping Agency names TB-500 under section S2 of its Prohibited List, as thymosin-beta-4 and its derivatives, prohibited at all times. BPC-157 is named explicitly under section S0, the non-approved substances clause, which is also prohibited at all times. The two sit in different sections and both are prohibited in and out of competition. Any competing athlete using either faces a straightforward anti-doping rule violation. WADA also does not distinguish between a research preparation and a clinical one, so the format of the device is irrelevant to that determination.

KPV is worth naming here because it is the third peptide most often added to stacks of this kind. It is the C-terminal tripeptide of alpha-MSH, lysine-proline-valine, an anti-inflammatory sequence with its own small literature in colitis models, and it is not in this device. Anyone assembling a stack around this pen should know which molecules are actually present, since KPV, BPC-157 and the thymosin fragment have three different mechanisms and three separate evidence bases.

What Should the Certificate Show for a Two-Peptide Device?

More than a single-compound CoA, and this is where two peptides in one cartridge complicate matters. Ask for purity by HPLC for each component separately, with the gradient described, since a single chromatogram covering both will not resolve the impurity profile of either cleanly. Ask for an accurate mass for each. Ask for the ratio between the two, because a combined figure of 20mg says nothing about how that mass is divided, and the ratio is the one number a purchaser cannot work out from the outside.

A CoA for a solution device should also state concentration, pH, excipient system and fill date. A single pH has to serve both peptides here, and the pH that suits one may not suit the other, which is a real formulation compromise rather than a theoretical one. Where a supplier can only offer a CoA for the raw materials that went into the fill, that CoA describes what was weighed out rather than what is in the cartridge now.

Side effects have never been catalogued for either compound in a controlled human study, so the record is empty rather than clean. An absent side effects table is a measure of how little has been done. Subcutaneous administration of these preparations has no established safety data, no toxicology package exists in any species for either molecule, and peptide therapy providers offering this pairing are working from mechanism and anecdote. Peptide therapy protocols for this stack were written by the people selling it. This device is supplied for laboratory research and neither synthetic peptide in it is a medicine anywhere.

Published Literature

All eight entries were checked in PubMed, Crossref or the publisher record before listing. None examined a co-formulated solution of the two peptides.

1. He L, Feng D, Guo H, et al. Pharmacokinetics, distribution, metabolism, and excretion of body-protective compound 157, a potential drug for treating various wounds, in rats and dogs. Front Pharmacol. 2022;13:1026182. DOI: 10.3389/fphar.2022.1026182
2. Mateescu DM, Gavrilescu DM, Constantinescu FE, et al. BPC-157 as an investigational peptide therapeutic: biopharmaceutical challenges, formulation strategies, and translational development barriers. Pharmaceutics. 2026;18(5):625. DOI: 10.3390/pharmaceutics18050625
3. McGuire FP, Martinez R, Lenz A, et al. Regeneration or risk? A narrative review of BPC-157 for musculoskeletal healing. Curr Rev Musculoskelet Med. 2025;18(12):611-619. DOI: 10.1007/s12178-025-09990-7
4. Bicer O, Adanir O, Guleryuz Y, et al. Effects of BPC-157 and TB-500 on Achilles tendon healing in rats: a histopathological and biomechanical study. Jt Dis Relat Surg. 2026;37(3):822-837. DOI: 10.52312/jdrs.2026.2951
5. Esposito S, Deventer K, Goeman J, et al. Synthesis and characterization of the N-terminal acetylated 17-23 fragment of thymosin beta 4 identified in TB-500. Drug Test Anal. 2012;4(9):733-738. DOI: 10.1002/dta.1402
6. Ruff D, Crockford D, Girardi G, et al. A randomized, placebo-controlled, single and multiple dose study of intravenous thymosin beta4 in healthy volunteers. Ann N Y Acad Sci. 2010;1194:223-229. DOI: 10.1111/j.1749-6632.2010.05474.x
7. Sosne G, Ousler GW, McLaughlin J. Thymosin beta 4 ophthalmic solution for dry eye: a randomized, placebo-controlled, phase II clinical trial. Clin Ophthalmol. 2015;9:877-884. DOI: 10.2147/OPTH.S80954
8. Chang CH, Tsai WC, Lin MS, et al. The promoting effect of pentadecapeptide BPC 157 on tendon healing involves tendon outgrowth, cell survival, and cell migration. J Appl Physiol. 2011;110(3):774-780. DOI: 10.1152/japplphysiol.00945.2010

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