Healing & Recovery

Larazotide

Larazotide acetate · AT-1001 · zonulin antagonist

researchpopularoral capsule

What it is

Larazotide is an 8-amino-acid peptide that targets tight junctions in the gut lining. It blocks the action of zonulin (the protein that opens up gut tight junctions), helping reverse "leaky gut." Originally developed by 9 Meters Biopharma for celiac disease and made it to Phase 3 trials. The most evidence-based "leaky gut" intervention.

How it works

Antagonizes zonulin signaling at the gut epithelium. Tightens the spaces between intestinal cells, reducing the passage of large molecules (like undigested food proteins or bacterial fragments) into the bloodstream. Result: less systemic inflammation and immune activation from gut sources.

Benefits

Reduced intestinal permeability (objectively measurable on tests)
Reduced symptoms of celiac disease in gluten-exposed patients
Possible benefits for autoimmune conditions linked to leaky gut
Anti-inflammatory effects
Often used in functional medicine for IBS, Hashimoto's, etc.

Timeline

Week 2–4: Possible reduction in GI symptoms.
Month 1–3: Cumulative gut barrier improvements.

Dosing & titration

Standard dose0.5–1 mg orally, 3x daily before meals

Cycle length8–12 weeks, then assess

Timing15–30 min before each meal

When to titrate upPhase 3 trial dose was 0.5 mg 3x daily. Higher doses didn't improve outcomes in trials.

Side effects & risks

Generally very well tolerated in trials
Mild GI symptoms (rare)
Headache (rare)
Phase 3 missed primary endpoint in celiac trial — efficacy debate ongoing

Best paired with addressing root cause (gluten exposure, dysbiosis, etc.). Larazotide is not a magic bullet on its own.

Typical price

$80–$200/moCompounded oral capsules from a 503A pharmacy.

Studies

Leffler DA et al. Larazotide acetate for persistent symptoms of celiac disease despite a gluten-free diet: a randomized controlled trial — Phase 2b trial. PubMedGastroenterology, 2015
Search PubMed for larazotide — PubMed searchLive PubMed search

Educational reference only. Not medical advice.