Wolverine Stack — BPC-157 & TB-500

The Yakka Strength Wolverine Stack is the manufacturer's name for a capsule bundle of two research peptides, BPC-157 (Body Protection Compound 157, also sold as BPC157) and TB-500 (TB500, a synthetic fragment of thymosin beta-4). The name is a marketing label and is not a claim about what the peptides do. Yakka Strength lists the pack as 60 capsules and does not state a peptide content per capsule, so we do not quote one. Supplied to adults for laboratory research only and not for human consumption.

A bundle is a listing convenience only: it lets products from one manufacturer be ordered in a single purchase. Nothing on this page claims that they act together or should be studied together, and Free Muscle publishes no stack or cycle guidance for any product. Each peptide is therefore described on its own below.

About the compounds in this bundle

BPC-157

BPC-157 is a synthetic fifteen-amino-acid peptide based on a sequence from a human gastric protein. Almost all published work is rodent and cell research, largely from one Croatian group, covering animal models of gut, tendon, muscle and vascular injury. Its developers mention early trials in inflammatory bowel disease, but no controlled human trial has been published in full, and oral absorption is unproven. WADA lists it under S0 (non-approved substances). Compare brands on the BPC-157 collection page.

TB-500 (Thymosin Beta-4 fragment)

TB-500 is the trade name for a synthetic fragment of thymosin beta-4, a 43-amino-acid actin-binding peptide found in most human and animal cells. Reviews of thymosin beta-4 cover preclinical wound, corneal and cardiac repair models and early clinical trials of the full peptide. TB-500 itself has no published human data. When anti-doping chemists at Ghent University analysed a TB-500 product in 2012, the peptide they identified was the N-terminally acetylated 17-23 segment of thymosin beta-4, written Ac-LKKTETQ, not the whole protein. WADA names thymosin beta-4 and its derivatives, including TB-500, under S2. Compare brands on the TB-500 (Thymosin Beta-4 fragment) collection page.

Identifiers

What the published research reports

For BPC-157, the most cited overview is a 2016 review by the originating Zagreb group, which gathers its own rodent findings on the gut, brain and blood vessels and proposes a brain-gut axis role. Its main limitation is that it reviews largely single-laboratory work. For thymosin beta-4, a 2012 review by Goldstein and colleagues describes actin binding, cell migration and repair findings in animal models and early human studies of the full-length protein applied to skin and eye. Neither review concerns this product or TB-500 as sold, and none of it is a claim about the bundle. The BPC-157 research article and the TB-500 and thymosin beta-4 research guide go further.

Both peptides are supplied here in capsule form. Whether peptides survive the digestive tract in any meaningful quantity is an open question, discussed in our article Do oral peptides actually work?.

This listing

• Brand: Yakka Strength (third-party brand, Muscle Market)
• Compounds: BPC-157 and TB-500 (thymosin beta-4 fragment)
• Form and pack size: 60 capsules, as listed by the manufacturer
• Peptide content per capsule: not stated by the manufacturer
• Total milligrams per pack: cannot be worked out without a stated strength
• COA: only where Yakka Strength supplies one for the batch held
• Sold to adults aged 18 and over, for laboratory research only

The two peptides are also listed singly as Yakka Strength BPC-157 capsules and Yakka Strength TB-500 capsules.

BPC-157 and TB-500 in the UK: buying, legal status and what to check

Searches such as "BPC157 TB500 UK", "buy TB 500 UK" and "TB 500 legal UK" come down to three questions: is it lawful to sell, who is a credible supplier, and what the listing should prove.

Legal position

None of the compounds on this page is a licensed medicine in the United Kingdom, none has been assessed by the MHRA and none is an authorised food supplement. Neither peptide is a controlled drug. They are supplied only as research materials, never for human consumption. Free Muscle supplies them to adults aged 18 and over for laboratory research only. There is no licensed product containing either peptide, so neither is available on prescription. BPC-157 is listed by WADA under S0 and TB-500 under S2, and both are prohibited at all times in tested sport. Buyers are responsible for the rules that apply to them. Our SARMs research guide has more background.

What a trustworthy UK listing shows

• Both compounds named separately, with the manufacturer identified, rather than a blend described only by a nickname.
• A lot or batch number on each container, because test results attach to batches, not to product names.
• A certificate of analysis for that batch, covering each peptide in the bundle.
• A stated strength per capsule for each peptide, or an honest note that none is given.
• Sale terms that match the law: adults only, laboratory use stated, and no usage instructions or promised effects.
• A traceable UK seller with tracked delivery, plain packaging and a written returns policy.

How this listing measures up

FreeMuscle LTD is a UK company based in Scunthorpe. The manufacturer is named, sales are restricted to adults and this page gives no directions for use. Every order ships by free tracked UK delivery in plain packaging, orders placed before 2pm Monday to Friday are processed the same working day, EU delivery takes 3 to 7 working days, and unopened items can be returned within 30 days. Two points depend on Yakka Strength: the label gives no per-capsule strength, so that check is not met, and a certificate appears only where one has been supplied for the batch we hold. Our UK supplier checklist sets out these checks in full, and delivery terms are on the shipping page.

Capsules compared with other forms

BPC-157 and TB-500 are both offered as capsules or tablets, as freeze-dried powder in sealed vials, and occasionally as pre-mixed liquids. The research literature on both peptides relies overwhelmingly on injection: into the abdominal cavity or muscle in rodent studies of BPC-157, and by injection or topical application in thymosin beta-4 work. Some Zagreb experiments gave BPC-157 in drinking water, but no study has measured blood levels in people after an oral dose of either peptide.

The obstacle for any swallowed peptide is enzymatic. Pepsin in the stomach and trypsin, chymotrypsin and brush-border peptidases in the small intestine cleave peptide bonds, and short linear chains such as a 15-residue or 7-residue peptide are ordinary substrates. The originating group reports that BPC-157 resists human gastric juice in its own tests; no equivalent claim has been published for the TB-500 fragment. Whether either survives in meaningful amounts is unresolved, which is the subject of BPC-157 capsules vs injection: what the studies used.

As materials, the formats behave differently. Dry powder, in a capsule or sealed vial, is more stable than peptide in solution. Fill accuracy is another difference: a capsule's content depends on how evenly the powder was blended with filler before encapsulation, while a liquid's depends on how accurately it was made up and measured. None of this implies that any format produces an effect.

BPC-157 compared with TB-500

"TB 500 vs BPC 157" is the comparison searched most often for this pair. Though often sold side by side, they are unrelated, with different parent proteins, different research traditions and different anti-doping classifications.

• Origin. BPC-157 is a 15-residue sequence (GEPPPGKPADDAGLV) derived from a protein in gastric juice. TB-500 is built around residues 17 to 23 of thymosin beta-4, the segment linked to actin binding.
• Proposed mechanism. Work on BPC-157 points to growth factor, nitric oxide and cell-signalling pathways in rodent tissue. Thymosin beta-4 is best known for holding a pool of unpolymerised actin, which influences how cells migrate.
• Evidence base. BPC-157 has rodent and cell studies, mostly from one research network, and no published randomised human trial. Thymosin beta-4 has animal studies from many laboratories and small early human trials of the full protein; the TB-500 fragment itself has none.
• Regulatory status. Both are unlicensed research compounds in the UK, with no approval from the MHRA, EMA or FDA.
• WADA class. S0 for BPC-157, as a substance with no therapeutic approval; S2 for TB-500, because the list names thymosin beta-4 and its derivatives.

Is TB-500 the same as thymosin beta-4?

No, although the names are often used interchangeably. Thymosin beta-4 is the whole 43-residue protein, about 4,963 g/mol. The product sold as TB-500 was shown by laboratory analysis to contain the acetylated seven-residue fragment Ac-LKKTETQ, a far smaller molecule. No human study has compared BPC-157 with TB-500, so neither can be ranked above the other, and we give no guidance on studying them together. Single-compound listings are on the TB-500 collection and BPC-157 collection pages, and the wider class is covered in SARMs vs peptides.

Reading the certificate of analysis for this product

Yakka Strength is a third-party brand sold through Muscle Market. For third-party brands we display a certificate of analysis only where the manufacturer supplies one for the exact batch we hold; if none is shown, none has been supplied and we do not substitute a generic document. Free Muscle-brand products, by contrast, are assayed batch by batch at Janoshik Analytical, with the certificate sent on request by email, as with our own BPC-150 capsules. That testing does not extend to Yakka Strength.

A certificate covering one peptide says nothing about the other, so read each line against the pack:

• Compound named. The report should say whether it covers BPC-157, TB-500 or both, and which container it belongs to.
• Identity method. HPLC compares retention time with a reference standard; LC-MS also measures molecular mass. For TB-500, the mass found should match the small acetylated fragment, not the full thymosin beta-4 protein, which is one of the clearest identity checks available.
• Purity percentage. How much of the detected material is the named peptide rather than synthesis by-products; a high figure says nothing about the quantity in a capsule.
• Content per capsule. The only figure that could supply the strength missing from this label. It should say whether it reports net peptide or total powder.
• Batch number and test date. These must match the lot printed on the container and show how recent the analysis is.
• Laboratory name. An unnamed lab cannot be asked to confirm that it issued the report.

For this brand, a missing field matters directly: with no content line the strength stays unknown, and a report without a batch number cannot be linked to the capsules in hand. To ask what exists for current stock, send the batch number on the pack through our contact page. Our lab testing page explains what a certificate shows, and how to read a certificate of analysis works through an example.

Detection, sport and testing

Both peptides are prohibited at all times, in and out of competition, under the World Anti-Doping Code, which UK Anti-Doping applies in the UK. BPC-157 is named in S0, the class for substances with no current approval for human therapeutic use. TB-500 falls under S2 through thymosin beta-4 and its derivatives. Strict liability applies, so an athlete is responsible for whatever is found in a sample, whatever the label said.

Anti-doping laboratories have published methods for each. In 2012 the Ghent doping control laboratory identified Ac-LKKTETQ in a TB-500 product by high-resolution mass spectrometry, synthesised a reference standard and proposed a strategy for finding it in plasma and urine. In 2017 the Salt Lake City laboratory validated a urine test for BPC-157 with a limit of detection of 0.1 ng/mL, found the peptide stable in urine for at least four days, and improved specificity by measuring a stable metabolite as well. Neither study established how long either peptide stays detectable after human exposure, so the accurate position for both is detectable, window not established.

Storage, stability and handling

No published stability study covers BPC-157 or TB-500 in capsule form, so the expiry or best-before date printed by the manufacturer, if there is one, is the limit to observe. General peptide chemistry indicates the main risks. Water drives hydrolysis of peptide bonds and makes powder clump and gelatin shells soften. Heat speeds up degradation and some amino acids oxidise over time, a process that light can accelerate.

Keep each container tightly closed in a cool, dry, dark cupboard, away from heaters and steamy rooms, with any desiccant left in place. If a container is refrigerated, allow it to reach room temperature before opening so moisture does not condense inside. Keep capsules in the original container that carries the batch number, so they can still be matched to a certificate. Handle the contents as laboratory reagents: gloves when working with opened capsules, separation from food and drink, storage out of reach of children and pets, and disposal as chemical waste rather than down a drain.

Glossary

• Actin: a structural protein inside cells; thymosin beta-4 binds its unpolymerised form.
• Acetylation: addition of an acetyl group, here to the start of the TB-500 fragment, marked "Ac-" in its sequence.
• Protease: an enzyme that cuts peptide bonds, found throughout the digestive tract.
• Retention time: how long a compound takes to pass through a chromatography column, used to match it to a standard.
• High-resolution mass spectrometry: measurement of molecular mass precise enough to separate compounds of very similar weight.
• S0 and S2: WADA Prohibited List sections for non-approved substances and for hormones, growth factors and related substances.
• Strict liability: the anti-doping rule that an athlete answers for any prohibited substance in a sample.

Related

• BPC-157 collection
• TB-500 (Thymosin Beta-4) collection
• Yakka Strength brand page
• Peptides collection
• Bundles collection
• Delivery and returns

Supplied for laboratory research use only. Not a medicine, not evaluated by the MHRA, EMA or FDA, and not for human consumption. Buyers must be 18 or over. Nothing on this page is medical or dosing advice or a recommendation to use, stack or cycle any compound; research summaries describe findings in study participants or animals, not claims about this product.

References

1. Sikiric P, et al. Brain-gut Axis and Pentadecapeptide BPC 157: Theoretical and Practical Implications. Curr Neuropharmacol. 2016;14(8):857-865. PMID: 27138887.
2. Goldstein AL, et al. Thymosin beta4: a multi-functional regenerative peptide. Basic properties and clinical applications. Expert Opin Biol Ther. 2012;12(1):37-51. PMID: 22074294.
3. Esposito S, et al. 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 Test Anal. 2012;4(9):733-8. PMID: 22962027.
4. Cox HD, et al. Detection and in vitro metabolism of the confiscated peptides BPC 157 and MGF R23H. Drug Test Anal. 2017;9(10):1490-1498. PMID: 28035768.