Repair and gut peptides
The most used healing peptides, BPC-157 and TB-500, rest almost entirely on animal studies. Thymosin beta-4, ARA-290 and larazotide reached controlled human trials, but none was approved.
- Compounds
- 10
- Approved drug
- 0
- Human studies
- 4
- Preclinical
- 3
- Blends
- 3
Members
BPC-157 and thymosin beta-4
BPC-157 is a piece of a stomach protein; TB-500 is a seven-amino-acid fragment of thymosin beta-4, a different molecule from the full protein.
| Compound | What it is | Approval | Evidence | How often | Half-life | Sport |
|---|---|---|---|---|---|---|
| BPC-157 | Tissue-repair peptide | Not approved | Preclinical | 1–2× daily | under 30 minutes Animal | Banned |
| TB-500 | Tissue-repair peptide | Not approved | Preclinical | 2× per week, then weekly | Not measured | Banned |
| Thymosin Beta-4 | Actin-binding repair peptide | Investigational | Human studies | 2× per week, then weekly | Not measured | Banned |
Other repair peptides
ARA-290 comes from EPO, the red-blood-cell hormone; KPV is the tail end of alpha-MSH; GHK-Cu is a copper-binding peptide found naturally in blood.
| Compound | What it is | Approval | Evidence | How often | Half-life | Sport |
|---|---|---|---|---|---|---|
| ARA-290 | Tissue-protective peptide (EPO-derived) | Investigational | Human studies | Once daily | about 20 minutes Trial | Banned |
| KPV | Anti-inflammatory peptide | Not approved | Preclinical | Once daily | Not measured | Likely banned |
| GHK-Cu | Copper peptide | Not approved | Human studies | Once daily | Not measured | Likely banned |
Blends
BPC-157 + TB-500 comes as one vial; GLOW and KLOW are fixed blends built around the copper peptide GHK-Cu.
| Compound | What it is | Approval | Evidence | How often | Half-life | Sport |
|---|---|---|---|---|---|---|
| BPC-157 + TB-500 | Repair blend | Blend | Blend | Once daily | See each part | Banned |
| GLOW blend | Skin and repair blend | Blend | Blend | Once daily | See each part | Banned |
| KLOW blend | Skin, repair and anti-inflammatory blend | Blend | Blend | Once daily | See each part | Banned |
Gut barrier
A capsule that acts inside the gut to keep the seals between lining cells closed, tested in celiac disease.
| Compound | What it is | Approval | Evidence | How often | Half-life | Sport |
|---|---|---|---|---|---|---|
| Larazotide | Tight-junction regulator (gut barrier) | Not approved | Human studies | 3× daily before meals | Not measured | Likely banned |
Approval, evidence, half-life and sport status restate each compound’s own page, where the sources are listed. Select a name for doses, side effects and studies.
How they work
BPC-157 is a 15-amino-acid piece of a protein found in gastric juice, and no receptor for it has been found. In rat and cell studies it is linked to new blood vessel growth, through VEGFR2, a receptor that drives vessel growth, and nitric oxide; to faster migration of tendon cells; and to protection of the stomach and gut lining. A 2025 review of the orthopedic research found 36 studies, 35 of them in animals or cells. Animal
Thymosin beta-4 is a 43-amino-acid protein nearly all cells make. It binds G-actin, the single units of the cell’s internal scaffolding, holding a pool that cells draw on when they move, and in animals it speeds skin and eye healing and promotes new blood vessels. TB-500 is its acetylated seven-amino-acid stretch, residues 17–23, which holds the actin-binding part. No study has given TB-500 to a person. Animal
ARA-290 (cibinetide) is an 11-amino-acid copy of one face of erythropoietin (EPO), the hormone that drives red blood cell production. It switches on the innate repair receptor, found on injured tissue, without raising red cell counts; in trials, small nerve fibers in the cornea grew and nerve-symptom scores fell. Larazotide, an eight-amino-acid peptide, stays in the gut and acts on tight junctions, the seals between lining cells. In a 21-person gluten challenge, gut leakiness rose 70% on placebo but not on larazotide. Trial
KPV, the last three amino acids of alpha-MSH, a hormone known mainly for darkening skin, entered gut lining and immune cells through PepT1, a transporter for small peptides, and blocked NF-kB, a switch for inflammatory messengers; taken by mouth, it eased gut inflammation (colitis) in mice. The GLOW and KLOW blends combine BPC-157 and TB-500 with GHK-Cu, a copper peptide, and KLOW adds KPV. No blend has been studied as a mix. Animal
How they differ
Human evidence
TrialARA-290: small Phase 2 trials (22–64 people), where 4 mg daily for 28 days improved nerve measures. Larazotide: about 700 adults in six celiac trials; in the largest only 0.5 mg beat placebo, and Phase 3 stopped in 2022. Thymosin beta-4: eye drops missed their main goals in two Phase 3 dry-eye trials.
Community doses
CommunityBPC-157: 250–500 mcg once or twice daily. TB-500: 2–2.5 mg twice weekly while loading, then weekly. KPV: 200–500 mcg daily. Blends are dosed by one component’s share. None of these doses comes from a trial.
Trial doses
TrialARA-290: 4 mg under the skin once daily for 28 days. Larazotide: 0.5 mg by mouth three times daily before meals, added to a gluten-free diet. Thymosin beta-4: 0.1% eye drops, or IV infusions in a safety study.
TB-500 is not thymosin beta-4
TB-500 is a seven-amino-acid fragment; thymosin beta-4 is the full 43-amino-acid protein. FDA treats them as different substances, and only the full protein has been given to people, as IV infusions, eye drops and wound gel.
History
- 1981Thymosin beta-4, a 43-amino-acid peptide, is isolated from calf thymus and sequenced.
- 1991Thymosin beta-4 is found to be the peptide that holds much of the free actin in platelets and other cells, present well beyond the thymus.
- 1993Researchers in Zagreb describe BPC, a gastric juice protein, and its 15-amino-acid fragment, BPC 157.
- 2008An 11-amino-acid peptide copying one face of EPO is shown to protect tissue in rodents without raising red blood cell production; it is the peptide later developed as ARA-290.
- 2022Larazotide’s Phase 3 celiac trial, with 307 people enrolled, is stopped by its sponsor after an interim analysis.
Comparisons and guides
Questions
What are healing peptides?
Peptides sold to speed recovery of tendons, muscles, skin or the gut. The most used, BPC-157 and TB-500, have almost no human data, and their doses come from user reports and clinic guides. A few relatives, such as ARA-290 and larazotide, reached human trials, but none is approved.
Is BPC-157 FDA-approved?
No. It isn’t approved anywhere. Its human record is three small uncontrolled reports with 30 people, and WADA bans it at all times. In July 2026 FDA’s advisory committee voted to recommend allowing it in pharmacy compounding, against FDA staff advice; FDA makes the final decision.
What is the difference between TB-500 and thymosin beta-4?
TB-500 is a seven-amino-acid fragment of thymosin beta-4, the stretch that binds actin. Thymosin beta-4 is the full 43-amino-acid protein, tested in people as IV infusions, eye drops and wound gel; TB-500 has never been tested in a person. FDA treats them as different substances, and vials may hold either.
Which repair peptides have human trials?
ARA-290 (Phase 2 trials in small-fiber nerve damage), larazotide (celiac trials in about 700 adults) and thymosin beta-4 (eye drops, wound gel and IV safety trials). None led to an approval: larazotide’s Phase 3 stopped in 2022, and thymosin beta-4’s dry-eye trials missed their main goals.
Are BPC-157 and TB-500 banned in sport?
Yes. WADA’s 2026 list names BPC-157 under S0, non-approved substances, and TB-500 and thymosin beta-4 under S2.3, growth factors. All three are banned at all times, in and out of competition, and so are blends that contain them.
Sources
- FDA briefing document for TB-500-related bulk drug substances, Pharmacy Compounding Advisory Committee (July 2026)
- Vasireddi et al., BPC-157 in orthopaedic sports medicine, systematic review (HSS J 2025) PMID 40756949
- Sikirić et al., a new gastric juice peptide, BPC (J Physiol Paris 1993) PMID 8298609
- Low et al., complete amino acid sequence of thymosin beta-4 (Proc Natl Acad Sci U S A 1981) PMID 6940133
- Safer et al., thymosin beta-4 and Fx, an actin-sequestering peptide, are indistinguishable (J Biol Chem 1991) PMID 1999398
- Brines et al., nonerythropoietic tissue-protective peptides derived from erythropoietin (Proc Natl Acad Sci U S A 2008) PMID 18676614
- Culver et al., cibinetide and corneal nerve fiber abundance in sarcoidosis (Invest Ophthalmol Vis Sci 2017) PMID 28475703
- Paterson et al., single doses of AT-1001 (larazotide) in celiac disease with a gluten challenge (Aliment Pharmacol Ther 2007) PMID 17697209
- Leffler et al., larazotide for persistent celiac symptoms, Phase 2b (Gastroenterology 2015) PMID 25683116
- CeDLara Phase 3 trial of larazotide, registry record (terminated by sponsor, 307 enrolled) NCT03569007
Each compound’s page lists the sources for its own doses, status and studies.