Larazotide vs TB-500
A neutral, side-by-side comparison of two healing & recovery peptides — their mechanisms, dosing ranges, administration routes, side effects, and research evidence. For research and educational purposes only.
Larazotide
Larazotide (AT-1001) is a synthetic octapeptide that acts as a tight junction regulator — it competitively blocks zonulin, the primary physiological driver of intestinal permeability ('leaky gut'). It is one of the few compounds studied in human clinical trials specifically for tight junction dysfunction, with Phase 2 data in celiac disease demonstrating reduced intestinal permeability and symptom improvement even in the presence of ongoing gluten exposure.
Full profileTB-500
TB-500 is a synthetic fragment of Thymosin Beta-4, an endogenous protein involved in cell migration, tissue repair, and inflammation regulation. It has shown significant healing properties in preclinical models across muscle, tendon, ligament, and cardiac tissue.
Full profile| Larazotide | TB-500 | |
|---|---|---|
| Category | Healing & Recovery | Healing & Recovery |
| Also known as | Larazotide acetate, AT-1001, INN-202 | Thymosin Beta-4, Tβ4, TB500 |
| Evidence | FDA-approved | Preclinical only |
| Dosing range | 0.25mg–1mg mg, 3x daily (before meals) | 2mg–10mg mg, twice weekly (loading), weekly (maintenance) |
| Administration | Oral (capsule), Subcutaneous injection (research use) | Subcutaneous injection, Intramuscular injection |
| Key side effects | Headache (most commonly reported adverse event in trials), Nausea (mild), Generally well-tolerated — adverse event rate similar to placebo in clinical trials | Head rush / lightheadedness (transient), Lethargy at higher doses, Injection site discomfort, Nausea (rare) |
| Cited sources | 3 references | 2 references |
Key differences
- Evidence level differs: Larazotide is fda-approved, while TB-500 is preclinical only.
- Administration: Larazotide — Oral (capsule), Subcutaneous injection (research use); TB-500 — Subcutaneous injection, Intramuscular injection.
- Frequency: Larazotide is typically 3x daily (before meals); TB-500 is twice weekly (loading), weekly (maintenance).
- Research depth: this profile cites 3 sources for Larazotide vs 2 for TB-500.
How each works
Larazotide
Zonulin upregulation disrupts the tight junction proteins occludin and claudin, allowing paracellular passage of antigens, LPS, and inflammatory triggers into systemic circulation. Larazotide acts as a tight junction agonist by competitively displacing zonulin from its receptor and directly stabilizing tight junction complexes. The Phase 2b CeD trial (N=342) showed larazotide reduced the ratio of lactulose/mannitol (L/M ratio, standard intestinal permeability marker) and improved GI symptom scores versus placebo in actively-challenged celiac patients.
TB-500
TB-500 promotes healing by upregulating actin, which drives cell migration to injury sites. Animal studies show accelerated repair of muscle tears, tendon injuries, and corneal wounds. It also demonstrates anti-inflammatory properties and has been studied for cardiac tissue repair following ischemic injury.
This comparison aggregates public research and structured profile data for informational purposes only. It is not medical advice and does not recommend either compound for human use. Consult a qualified healthcare provider before considering any peptide.