About Larazotide
Synthetic octapeptide that prevents zonulin-mediated tight junction opening; maintains intestinal epithelial barrier integrity
Larazotide acetate (AT-1001) is a synthetic octapeptide zonulin antagonist that reduces intestinal permeability by blocking zonulin-mediated disassembly of intestinal epithelial tight junctions, studied as an adjunctive treatment to reduce symptom burden in celiac disease patients during inadvertent or deliberate gluten exposure. By inhibiting zonulin receptor signaling, larazotide prevents the disruption of tight junction proteins — including occludin and claudins — that would otherwise permit immunogenic gluten peptides to traverse the epithelial barrier and trigger the CD4+ T-cell-mediated mucosal injury characteristic of active celiac disease. A Phase 2 randomized, double-blind trial published in The American Journal of Gastroenterology demonstrated that larazotide acetate reduced activation of celiac disease during gluten challenge; however, the Phase 3 trial published in Gastroenterology, designed to evaluate larazotide for persistent symptoms in celiac disease patients already following a gluten-free diet, did not meet its primary endpoint. Larazotide has not received FDA approval; no NDA has been filed following the Phase 3 outcome, and it remains an investigational compound with no approved indication.
Larazotide Benefits & Research Areas
Research Signals
Population research notes
These signals reflect research interest areas, not treatment indications.
Regulatory & Evidence
Risk Profile
Generally considered lower risk in research contexts. Risk profile varies by individual — review contraindications before use.
Regulatory Status
- Availability Status
- Research Only
- FDA Status
- Investigational
- Source
- View FDA source →
Tight junction regulator (AT-1001) for celiac disease. Phase 3 ILIT-1 (NCT02633956) failed primary endpoint 2019. No NDA filed. Additional Phase 3 planned by ImmunoGenX. Investigational.
Regulatory status reflects publicly available information and may change. This is not legal or medical advice.
Research Sources
3 sources cited · 1 strong · 2 moderate
2 RCTs · 1 Cohort
Larazotide acetate for persistent symptoms of celiac disease despite a gluten-free diet: a randomized controlled trial
Gastroenterology · 2015
In a 12-week phase 2 multicenter randomized controlled trial, larazotide acetate 0.5 mg three times daily significantly reduced celiac disease gastrointestinal symptoms compared with placebo in adults with celiac disease on a gluten-free diet, with 26% fewer symptomatic days and improvements in abdominal pain and non-gastrointestinal symptoms including fatigue.
Potassium-Competitive Acid Blocker Increases Ileal Permeability and Exacerbates Ileal Inflammation under Stress Conditions in a Mouse Model of Eosinophilic Enteritis.
Digestion · 2026
# Summary Research found that potassium-competitive acid blockers (P-CABs) increased intestinal permeability and worsened eosinophilic enteritis inflammation in mice exposed to psychological stress, while larazotide acetate (a zonulin inhibitor) demonstrated potential therapeutic benefit by reducing permeability and improving inflammation in this setting. This study demonstrated that the detrimental effects of P-CABs on the intestinal barrier appear to be stress-dependent and may be reversible through zonulin inhibition.
A randomized, double-blind study of larazotide acetate to prevent the activation of celiac disease during gluten challenge
American Journal of Gastroenterology · 2012
Research in a dose-ranging randomized controlled trial found that lower doses of larazotide acetate appeared to limit gluten-induced worsening of gastrointestinal symptoms in patients with celiac disease during a 14-day gluten challenge, supporting intestinal tight junction regulation as a therapeutic target for gluten sensitivity.
Larazotide Side Effects & Safety Considerations
Generally considered lower risk in research contexts. Individual response varies — review all considerations before use.
Reported contraindications & considerations
Consult a qualified healthcare professional before making any health decisions. This information is educational only and does not constitute medical advice.
Research Stacks
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Questions to Ask Your Provider
Frequently Asked Questions — Larazotide
Larazotide acetate (AT-1001) is a synthetic octapeptide zonulin antagonist that reduces intestinal permeability by blocking zonulin-mediated disassembly of intestinal epithelial tight junctions, studied as an adjunctive treatment to reduce symptom burden in celiac disease patients during inadvertent or deliberate gluten exposure. By inhibiting zonulin receptor signaling, larazotide prevents the disruption of tight junction proteins — including occludin and claudins — that would otherwise permit immunogenic gluten peptides to traverse the epithelial barrier and trigger the CD4+ T-cell-mediated mucosal injury characteristic of active celiac disease.
tight junction restoration, intestinal barrier repair, leaky gut prevention.
Research on Larazotide primarily documents effects related to tight junction restoration and intestinal barrier repair and leaky gut prevention. These are areas covered in preclinical and clinical literature — individual response varies and effects depend on context of use.
Reported contraindications and considerations for Larazotide include none established. This is educational information only — consult a qualified healthcare professional before use.
11 providers in the directory currently offer Larazotide.
In a 12-week phase 2 multicenter randomized controlled trial, larazotide acetate 0.5 mg three times daily significantly reduced celiac disease gastrointestinal symptoms compared with placebo in adults with celiac disease on a gluten-free diet, with 26% fewer symptomatic days and improvements in abdominal pain and non-gastrointestinal symptoms including fatigue.
Larazotide is featured in the following research stacks on PeptideBase: KPV + Larazotide: Gut Barrier & Anti-Inflammatory.