Larazotide (AT-1001) is a synthetic 8-amino acid peptide that acts as a tight junction regulator. It is being developed as an oral adjunct therapy for celiac disease, designed to reduce intestinal permeability ("leaky gut") triggered by gluten exposure. It is the first drug in its class and has completed Phase II clinical trials and a Phase III trial (INN-202, also called CeDLara). Larazotide works locally in the gut lumen without significant systemic absorption. It was originally developed by Alba Therapeutics and later acquired by Innovate Biopharmaceuticals (now 9 Meters Biopharma).
Category: Healing & Recovery. Evidence rating: B (meaningful human data).
Clinical status: Phase III completed (INN-202/CeDLara trial). Awaiting further development steps.
Larazotide acts as a zonulin antagonist, blocking the zonulin pathway that opens tight junctions in the intestinal epithelium. In celiac disease, gluten-derived gliadin peptides trigger zonulin release, which opens tight junctions and allows gliadin fragments to cross the epithelial barrier,…
Research base: 0 registered clinical trials and 2 indexed publications reference Larazotide.
Safety considerations: Well tolerated across Phase I, II, and III trials; Adverse event rates similar to placebo in controlled trials; No significant systemic absorption detected at therapeutic doses.
Reviewed by the PeptideAtlas Editorial Team. Last reviewed: 2026-08-12.
Related peptides: BPC-157, TB-500, Thymosin Beta-4.
Compare: Larazotide vs BPC-157, Larazotide vs TB-500, Larazotide vs Thymosin Beta-4.
Larazotide is being developed as an adjunct therapy for celiac disease. It is designed to reduce intestinal permeability caused by gluten exposure, not to replace a gluten-free diet. It would be used alongside dietary management to provide additional protection against inadvertent or small-amount gluten exposure.
No. Larazotide does not treat the underlying autoimmune pathology. It reduces the tight junction opening that allows gluten peptides to cross the intestinal barrier, potentially reducing symptom flares from inadvertent gluten exposure. A gluten-free diet remains essential.
In clinical trials, larazotide was not detectable in plasma at therapeutic doses, indicating it acts locally in the intestinal lumen with minimal to no systemic absorption. This is a favorable safety feature.