Larazotide

Grade B: Human evidence, not approved for this use

TL;DR: Larazotide acetate (AT-1001) is a synthetic octapeptide that acts as a tight-junction regulator, developed specifically as a pharmacological treatment for celiac disease symptoms. Multiple Phase 2 randomized controlled trials demonstrated modest symptomatic benefit: the most cited RCT (Fasano et al., PMID 25683116, n=342) found the 0.5 mg dose significantly reduced a celiac-specific gastrointestinal symptom score versus placebo (p=0.022) and reduced symptomatic days by 26%. However, higher doses (1 mg, 2 mg) showed no significant benefit in the same trial, suggesting a narrow and inconsistent dose-response. The pivotal Phase 3 trial (CedLara) was discontinued in June 2022 by 9 Meters Biopharma after an interim analysis determined the enrollment size needed to achieve statistical significance was not feasible, and the program has not been revived. As of 2026 there is no active IND-stage clinical development; larazotide acetate is not FDA-approved for any indication.

Key Takeaways

Grade B: Human evidence, not approved for this use
Not FDA approved: Not FDA-approved for any indication; Phase 3 development discontinued 2022 with no active development pipeline as of 2026.
Compounding: Not on the FDA 503A Category 1 (permitted) bulk drug substances list and not recognized as a compoundable substance as of June 2026. No IND-stage active program exists. Use in a compounded preparation would lack regulatory authorization.

Larazotide chemical structure — Structure via PubChem CID 9810532

Mechanism

Larazotide acetate blocks zonulin-mediated opening of intestinal epithelial tight junctions, thereby reducing paracellular permeability and limiting translocation of gluten peptides across the gut epithelium.

Evidence

Larazotide acetate (AT-1001) is a synthetic octapeptide that acts as a tight-junction regulator, developed specifically as a pharmacological treatment for celiac disease symptoms. Multiple Phase 2 randomized controlled trials demonstrated modest symptomatic benefit: the most cited RCT (Fasano et al., PMID 25683116, n=342) found the 0.5 mg dose significantly reduced a celiac-specific gastrointestinal symptom score versus placebo (p=0.022) and reduced symptomatic days by 26%. However, higher doses (1 mg, 2 mg) showed no significant benefit in the same trial, suggesting a narrow and inconsistent dose-response. The pivotal Phase 3 trial (CedLara) was discontinued in June 2022 by 9 Meters Biopharma after an interim analysis determined the enrollment size needed to achieve statistical significance was not feasible, and the program has not been revived. As of 2026 there is no active IND-stage clinical development; larazotide acetate is not FDA-approved for any indication.

Safety and risks

The safety profile from Phase 2 trials (up to 342 subjects) was broadly comparable to placebo, with no drug-related serious adverse events reported, no clinically meaningful changes in laboratory values, and no ECG abnormalities. The most common reported symptom in Phase 1 healthy-volunteer studies was mild headache. Because Phase 3 was discontinued for futility rather than a safety signal, no new major toxicity emerged from the expanded trial exposure. However, the full long-term safety profile at therapeutic doses is not established, since no multi-year controlled study has been completed. Any compounded or investigational-use preparations carry the added risks inherent to non-approved compounded injectables or peptides, including sterility, potency, and purity concerns not governed by FDA manufacturing standards. This compound should be considered investigational-only; use outside a registered clinical trial setting has no validated safety support.

Interactions

No clinically established drug interactions documented in available trial data; interaction studies have not been published.

Compounding legality

Not on the FDA 503A Category 1 (permitted) bulk drug substances list and not recognized as a compoundable substance as of June 2026. No IND-stage active program exists. Use in a compounded preparation would lack regulatory authorization.

Sources

Larazotide is Not FDA approved. PeptideGrids presents evidence and regulatory status for informational purposes only. We do not sell, supply, source, or help anyone obtain this compound, and we provide no dosing or administration guidance. This is not medical advice; consult a licensed clinician. Full disclaimer.

Last reviewed June 1, 2026 by PeptideGrids editorial team (independently audited).