Larazotide

Dosing from the Literature

Published for gut repair: celiac-trial doses of 0.25 to 8 mg three times a day, and 12 mg once a day in the first, three-day trial; in the largest trial only 0.5 mg beat placebo, on symptoms. Not published: a gut-permeability result better than placebo in the pooled trials, or the stopped Phase 3’s results.

The table records doses as each trial gave them. All were capsules or oral doses made for the trials, taken by mouth; they are trial doses, not recommendations.

What It Is

Larazotide is a synthetic peptide of eight amino acids, glycine-glycine-valine-leucine-valine-glutamine-proline-glycine (GGVLVQPG; C32H55N9O10, 725.8 Da), tested in people as its acetate salt, larazotide acetate (FDA substance registry UNII ZN3R5560ZV; PubChem). WHO proposed the international nonproprietary name in 2008 and lists it as a “zonulin antagonist (in celiac disease)” (WHO, 2008). Its development code was AT-1001; registries also list AT-2347, and its later developer called it INN-202 (FDA substance registry; NCT03569007).

Its story starts with cholera. In 1991 a University of Maryland group led by Alessio Fasano described a second toxin made by Vibrio cholerae, zonula occludens toxin (Zot), which raised the permeability of small-intestine tissue by acting on the tight junctions between its cells (Fasano et al., 1991). In 2000 the group reported a human protein that acts like Zot and named it zonulin (Fasano et al., 2000; Wang et al., 2000), and in 2001 it located an eight-amino-acid receptor-binding region in Zot by comparing the two (Di Pierro et al., 2001). The developers’ first human study describes larazotide’s structure as “derived from a protein secreted by Vibrio cholerae” (Paterson et al., 2007); a 2021 review co-written by staff of its later developer says it is “derived from human fetal zonulin and is structurally similar to Zot” (Slifer, Krishnan et al., 2021). In 2009 the Fasano group identified zonulin as prehaptoglobin-2, the uncut precursor of a blood protein (Tripathi et al., 2009). Two immunologists then wrote that the octapeptide “was thought to represent the N-terminal sequence of zonulin,” but that “in all likelihood” it comes from the rabbit antibody used to purify the protein, since neither prehaptoglobin-2 nor properdin, another protein proposed as zonulin, carries a similar sequence (Sollid & Koning, 2021).

Alba Therapeutics, a Baltimore company that Fasano co-founded, ran the first trials (Paterson et al., 2007; Leffler et al., 2012; Yonker et al., 2022); its 2011–2013 Phase 2b was designed with Alba and Cephalon/Teva (Leffler et al., 2015; NCT01396213). In 2016 Alba licensed larazotide to Innovate Biopharmaceuticals (9 Meters, 2022), which became 9 Meters Biopharma in 2020 (SEC filer record; Slifer, Krishnan et al., 2021). 9 Meters started a Phase 3 in 2019; on June 21, 2022 it announced that an interim analysis did not support continuing, and on August 15, 2022 it ended development in celiac disease (9 Meters, June 2022; 9 Meters, 2022). In July 2023 the company ceased operations and filed for Chapter 7 liquidation (9 Meters, 2023). The later trials in children with MIS-C and in Long COVID were sponsored by Massachusetts General Hospital (ClinicalTrials.gov); 9 Meters supplied larazotide for the MIS-C trial and in April 2022 licensed EBRIS, a research institute in Salerno, Italy, with which Fasano is affiliated, to study it in MIS-C (9 Meters, 2022; Yonker et al., 2022).

No approval of larazotide by any health authority turned up for this page: Drugs@FDA holds no application, and the European Medicines Agency’s list of medicines has no entry (see Legal Status). PubMed returns 81 records for “larazotide” (October 3, 2026); 11 of them are about two unrelated drugs that share its code, a nicotinic-receptor compound tested against nicotine self-administration in rats (Toll et al., 2012) and migalastat, a Fabry-disease drug also coded AT1001 (Benjamin et al., 2012). A PubMed search for either spelling of the code returns all three.

Mechanism of Action

Every finding below comes from cells, intestinal tissue or animals, and most of the cell work was done by the developers or in labs they funded. None of the mechanisms was confirmed in people.

• Tight-junction proteins and actin (ZO-1, occludin, claudins, E-cadherin) — In Caco-2 and IEC6 intestinal cells, larazotide blocked the rearrangement of ZO-1 and actin caused by gliadin fragments and by AT-1002, a six-amino-acid peptide from Zot; it blocked AT-1002’s drop in electrical resistance, reduced the passage of a 13-amino-acid gliadin peptide across Caco-2 layers, and, applied on the gut side, reduced the leak caused by cytokines applied on the other side (Gopalakrishnan, Durai et al., 2012). In a second Alba study it promoted tight-junction assembly in MDCK cells and lowered the leak through “leaky” Caco-2 layers (Gopalakrishnan, Tripathi et al., 2012).
• Zonulin–EGFR–PAR2 (a hypothesis) — The Fasano group reported that zonulin, as prehaptoglobin-2, raised permeability by transactivating the epidermal growth factor receptor through proteinase-activated receptor 2 (PAR2) (Tripathi et al., 2009). Larazotide is proposed to block zonulin at its receptors; the 2021 review co-written by the developer’s staff calls this a proposal that needs “further mechanistic studies” (Slifer, Krishnan et al., 2021). Two immunologists asked for evidence that it antagonizes purified prehaptoglobin-2 in tests of gut permeability (Sollid & Koning, 2021). Other groups describe it as a PAR2 inhibitor (Yang et al., 2023).
• Myosin light chain (MLC-2) and ROCK — In C2BBe1 and IPEC-J2 cells starved of oxygen and then reoxygenated, larazotide pretreatment raised electrical resistance, kept tight-junction proteins in place and reduced MLC-2 phosphorylation, “likely through modulation of the ROCK pathway”; three of the five authors were from Innovate Biopharmaceuticals (Kim et al., 2025). The 2021 review links it to inhibition of myosin light chain kinase (Slifer, Krishnan et al., 2021).
• Where it acts: the small intestine — In the 2012 trial, blood levels were below the limit of quantification (0.5 ng/mL) in every group, and metabolites were below it at 8 mg (Leffler et al., 2012). In pigs, a 1 mg dose of the delayed-release capsule used in the Phase 3 peaked at 0.32–1.76 µM in the duodenum and upper jejunum after one hour and was still present, at lower levels, two to four hours after the dose (Enomoto et al., 2021). In mice it worked only in the small intestine (Arrieta et al., 2009).
• Breakdown by gut enzymes — In pig intestine, the brush-border enzyme aminopeptidase M cut larazotide into fragments, and its half-life in injured tissue was 35 minutes. At 1 µM larazotide helped the tissue recover where 0.1 µM and 10 µM did not, and one fragment, missing both glycines at the start, blocked the recovery that 1 µM produced; the authors offer this as the reason higher doses worked less well (Slifer, Hernandez et al., 2021). The authors of the largest human trial wrote that why higher doses appeared less effective “is unclear” (Leffler et al., 2015).

What the Research Shows

The results below are in animals and animal tissue. The human studies are in the next section.

• Gluten-sensitive mice — In HLA-HCD4/DQ8 mice sensitized to gliadin, larazotide prevented gliadin-induced macrophage build-up in the gut and preserved tight-junction structure (Gopalakrishnan, Durai et al., 2012). In the same strain, it brought the leak across the jejunum back to normal but did not reduce bacteria crossing into the lymph nodes; the authors conclude that restoring this permeability “was not sufficient to prevent bacterial translocation” (Silva et al., 2012).
• Colitis in mice — In IL-10-deficient mice, which develop colitis, larazotide in drinking water from four weeks of age lowered small-intestine permeability (area under the lactulose/mannitol curve 3.97 on the high dose against 5.36 untreated), and by 17 weeks the TNF-α released by colon tissue was about a quarter of the untreated mice’s; one author sat on Alba’s scientific advisory board (Arrieta et al., 2009). In mice engineered to make zonulin, 40–70% died 11 days after DSS colitis against none of the normal mice, and larazotide in drinking water prevented the permeability rise and “completely reverted morbidity and mortality” (Sturgeon et al., 2017).
• Injured pig intestine — In jejunum from 6–8-week-old pigs injured by cutting off its blood supply, 1 µM larazotide raised electrical resistance, cut the leak of bacterial lipopolysaccharide and moved the sealing protein claudin-4 into place over four hours in Ussing chambers (Slifer, Hernandez et al., 2021).
• Beyond the gut, in rodents — Groups outside the developer report, in mice: less arthritis onset (Tajik et al., 2020); gut leak caused by bacterial strains from lupus patients reversed by larazotide by mouth (Silverman et al., 2022); fewer thoracic aortic aneurysms and dissections (Yang et al., 2023). A study with Fasano among its authors found less lung injury in mice when it was given into the airway or a vein (Rittirsch et al., 2013). In rats with pancreatitis, bacteria crossed the gut wall in 50% of treated animals against 100% untreated (Karahan et al., 2024); in rats with liver failure, gut damage was lower in the drinking-water group, but liver damage scores did not differ (Caliskan et al., 2021).

Human Data

Published: four randomized, double-blind, placebo-controlled trials in adults with celiac disease, all run by the developer, and three reports in children with MIS-C from one Boston group. Registered with no results published or posted: a Phase 1 in healthy volunteers, a Phase 2b in active celiac disease, the Phase 3 and a Long COVID trial (ClinicalTrials.gov, searched October 3, 2026).

• Phase 1b, 21 patients (Paterson et al., 2007) — An inpatient study in adults with celiac disease on a gluten-free diet: 14 took 12 mg and 7 took placebo, with a gluten challenge (NCT00386165). Adverse events were no more common than on placebo. After gluten, intestinal permeability rose 70% in the placebo group and not at all in the larazotide group; interferon-γ rose in 4 of 7 on placebo and 4 of 14 on larazotide; gastrointestinal symptoms were more frequent on placebo (P = 0.018).
• Phase 2a, 86 patients, 14 days (Leffler et al., 2012) — Adults with diet-controlled celiac disease took 0.25, 1, 4 or 8 mg or placebo three times a day, most with 2.4 g of gluten a day (NCT00362856). The main measure, the urinary lactulose/mannitol ratio, was “highly variable in the outpatient setting” and did not differ between larazotide and placebo. Larazotide “appeared to limit gluten-induced worsening of gastrointestinal symptom severity” at some lower doses but not at the higher dose.
• Phase 2b with gluten, 184 patients, 6 weeks (Kelly et al., 2013) — Patients on a gluten-free diet took 1, 4 or 8 mg or placebo three times a day with 2.7 g of gluten a day (NCT00492960). Lactulose/mannitol ratios did not differ from placebo. The 1 mg dose limited gluten-induced symptoms (P = 0.002). Anti-tissue-transglutaminase IgA rose to 19.0 times baseline on placebo, against 5.78, 3.88 and 7.72 times on 1, 4 and 8 mg. The authors call the study exploratory.
• Phase 2b, 342 patients with persistent symptoms, 12 weeks (Leffler et al., 2015) — At 74 North American sites, adults who had kept a gluten-free diet for at least 12 months and still had symptoms took 0.5, 1 or 2 mg or placebo three times a day after a 4-week placebo run-in (NCT01396213). The main endpoint, the average on-treatment Celiac Disease Gastrointestinal Symptom Rating Scale score, was met at 0.5 mg (P = 0.022 by analysis of covariance; P = 0.005 by mixed model), and among exploratory endpoints that dose gave 26% fewer symptomatic days (P = 0.017); the 1 and 2 mg doses “were no different than placebo for any end point.” The authors call the results mixed.
• The four trials pooled (Hoilat et al., 2022) — A meta-analysis of the four randomized trials, 626 patients (465 on larazotide, 161 on placebo), found no difference from placebo on the lactulose/mannitol ratio, with or without gluten. Symptoms improved more than on placebo in the gluten-challenge trials, but not in patients on a gluten-free diet alone.
• Unpublished early trials — Two registered trials have no published results and no results posted: a Phase 1 in 24 healthy volunteers, 0.25, 1 or 4 mg three times a day for 10 days, in 2006 (NCT00386490), and a Phase 2b in 105 adults with active celiac disease, 4 or 8 mg three times a day, judged by duodenal biopsy, completed in 2009 (NCT00620451). A 42-patient “Part B” of the 2013 trial’s protocol, 1 mg against placebo with gluten, completed in 2010 and posts no results either (NCT00889473).
• Phase 3, stopped (NCT03569007) — 9 Meters compared 0.25 and 0.5 mg three times a day with placebo in adults with symptoms despite a gluten-free diet, planning 525 patients, with 12 weeks double-blind and 12 more of safety follow-up. A pre-specified interim analysis by an independent statistician, of about the first half of the target enrollment, found that “the additional number of patients needed to determine a significant clinical outcome between placebo and larazotide is too large to support trial continuation” (9 Meters, June 2022). The registration lists 307 enrolled and the trial as terminated, ending on July 21, 2022, with the reason “Trial terminated by Sponsor.” No results are posted, and none have been published (PubMed and Europe PMC, October 3, 2026).
• Children with MIS-C, one Boston group — Multisystem inflammatory syndrome in children follows COVID-19 by weeks to months. In 2021 the Massachusetts General Hospital group reported one child whose spike antigen and inflammatory markers fell, with clinical improvement, after larazotide (Yonker et al., 2021). In 2022 it reported four children aged 3–17 given open-label larazotide, 10 µg/kg (up to 500 µg) four times a day for 21 days alongside steroids or IVIG: all tolerated it, and against 22 children on steroids or IVIG alone, gastrointestinal symptoms resolved faster (p = 0.03) and spike antigen cleared faster (p = 0.04) (Yonker et al., 2022). In 2025 it reported a Phase 2a randomized, double-blind, placebo-controlled trial in 12 children with a median age of 5.7: no larazotide-related adverse events, and on larazotide faster resolution of gastrointestinal symptoms, faster spike-antigen clearance and a faster return to usual activities (Yonker et al., 2025). The trial stopped at 12 of a planned 20 children; its registration gives the reason as “Decline in MISC cases” (NCT05022303). The senior author declared in 2021 and 2022 that he co-founded and holds stock in Alba Therapeutics.
• Long COVID, no results yet (NCT05747534) — A Phase 2a at the same hospital gave 250 or 500 µg, by body weight, or placebo four times a day for 21 days to people aged 7–50 with Long COVID and SARS-CoV-2 antigen in the blood. It lists 107 enrolled and completion on June 18, 2026; no results were posted or published by October 3, 2026.

The evidence meter on the Larazotide card reads “Controlled trials”: it counts published human data on larazotide itself, for gut repair, and four randomized, placebo-controlled celiac trials are published. Controlled is not the same as positive: the permeability test did not beat placebo when the trials were pooled, the one main endpoint met came at the lowest dose of the largest trial, and the Phase 3 meant to confirm it was stopped.

Reconstitution & Storage

There is nothing to reconstitute in the published human use: the trials gave capsules by mouth, three times a day, 15 minutes before meals (Leffler et al., 2012; Leffler et al., 2015). The capsules held enteric-coated beads (Leffler et al., 2012); the delayed-release version used in the Phase 3 mixed two kinds of beads with different coating thicknesses, designed to start releasing in the mid duodenum and finish in the upper jejunum, the part of the gut celiac disease damages (Enomoto et al., 2021; NCT03569007).

• Why the coating — In simulated stomach fluid only 0.7% of the capsule’s larazotide dissolved, and the formulation’s specification allows no more than 10% in stomach fluid over 120 minutes and requires at least 85% in intestinal fluid over 120 minutes (Enomoto et al., 2021). Gut enzymes cut larazotide into fragments, one of which blocked its effect in pig intestine (Slifer, Hernandez et al., 2021).
• Storage — No document read for this page gives storage conditions or a shelf life for the trial capsules or for bulk larazotide powder.
• Products outside the trials — What is sold is powder: bulk ingredient listed with FDA and lab reagent labelled for research use only (see Legal Status). No study has tested such a product in people, and no independent analysis of one has been published.

Side Effects & Risks

• In the celiac trials — No serious adverse events in the 2012 trial; the most common were headache and urinary tract infection. Five patients (5.8%) had urinary tract infections, all on larazotide with gluten; all were mild and none was judged drug-related (Leffler et al., 2012). In the largest trial, safety and tolerability were comparable with placebo at all doses, gastrointestinal events were the most frequent and equally common in every group, and there were no drug-related serious adverse events (Leffler et al., 2015). Adverse-event rates were similar to placebo in the 2013 trial (Kelly et al., 2013) and no higher than placebo in the first (Paterson et al., 2007).
• In children — All four children in the MIS-C case series tolerated it without adverse effects (Yonker et al., 2022), and the 12-child trial reported no larazotide-related adverse events over 24 weeks of follow-up (Yonker et al., 2025).
• Little reaches the blood — Blood levels were below the limit of quantification at every dose in the 2012 trial, which found no clinically significant liver, bone or kidney toxicity and no meaningful changes in vital signs, ECGs, blood counts or chemistry (Leffler et al., 2012).
• What has not been tested — The longest published course is 12 weeks (Leffler et al., 2015); the Phase 3’s 12-week safety phase was never published. No animal toxicology study, drug-interaction study or study in pregnancy turned up on PubMed (searched October 3, 2026).
• Not a substitute for a gluten-free diet — Every celiac trial kept patients on a gluten-free diet, and the gluten-challenge trials gave gluten in measured capsules, 2.4–2.7 g a day for two to six weeks (Leffler et al., 2012; Kelly et al., 2013; Leffler et al., 2015). No trial tested larazotide as a replacement for the diet.
• WADA — Larazotide is not named on the 2026 Prohibited List. Section S0 prohibits at all times substances not addressed elsewhere on the List “with no current approval by any governmental regulatory health authority for human therapeutic use (e.g. drugs under pre-clinical or clinical development or discontinued…)” (World Anti-Doping Agency, 2026). No approval of larazotide turned up for this page.

Bloodwork & Monitoring

No monitoring guidance for larazotide has been published outside the trials. The trials measured these:

• Celiac antibodies — Anti-tissue-transglutaminase and anti-deamidated-gliadin antibodies, measured centrally (Leffler et al., 2015); anti-transglutaminase IgA tracked the effect of gluten in the 2013 trial (Kelly et al., 2013).
• Standard safety tests — Blood chemistry, blood counts, urinalysis, ECGs and vital signs (Leffler et al., 2015; Leffler et al., 2012).
• The lactulose/mannitol test — A research measure of gut permeability, from sugars recovered in urine; it was “highly variable in the outpatient setting” (Leffler et al., 2012).
• “Zonulin” blood tests — A widely used commercial zonulin test did not detect prehaptoglobin-2, the protein identified as zonulin, and picked up other proteins, properdin the likeliest (Scheffler et al., 2018); in another lab, two commercial tests picked up complement C3 and haptoglobin, and the authors advise caution in using serum zonulin as a marker of the gut barrier (Ajamian et al., 2019).
• Symptom scores — The Gastrointestinal Symptom Rating Scale, its celiac version and a daily celiac symptom diary (Leffler et al., 2015).
• Which tests fit a given person — A question for a licensed healthcare provider. This page can’t answer it.

Commonly Stacked With

Larazotide has been tested only as an add-on: to a gluten-free diet in celiac disease, and to steroids or IVIG in children with MIS-C (Yonker et al., 2022). The other combinations below are suggested or promoted, not studied.

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References

1. World Health Organization. Proposed International Nonproprietary Names: List 99. WHO Drug Information. 2008;22(2):141. Larazotide: “glycylglycyl-L-valyl-L-leucyl-L-valyl-L-glutaminyl-L-prolylglycine,” zonulin antagonist (in celiac disease), C32H55N9O10. cdn.who.int/media/docs/default-source/international-nonproprietary-names-(inn)/pl99.pdf. Read October 3, 2026.
2. FDA. Global Substance Registration System: Larazotide, UNII ZN3R5560ZV (sequence GGVLVQPG; code AT-2347; CAS 258818-34-7; INN and USAN name). gsrs.ncats.nih.gov. Read October 3, 2026.
3. National Library of Medicine. PubChem: Larazotide, CID 9810532 (C32H55N9O10, 725.8 g/mol; synonyms include AT-1001 and AT-2347), and larazotide acetate, CID 44146842 (C34H59N9O12, 785.9 g/mol). pubchem.ncbi.nlm.nih.gov. Read October 3, 2026.
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36. Benjamin ER, Khanna R, Schilling A, Flanagan JJ, et al. Co-administration with the pharmacological chaperone AT1001 increases recombinant human α-galactosidase A tissue uptake and improves substrate reduction in Fabry mice. Mol Ther. 2012;20(4):717-726. PMID: 22215019.
37. Madabhushi S, Patel A, Tse-Kang S, Liu A, Amin D, Rupawala A. Scrolling for science: Assessing the quality and accuracy of Crohn’s disease-related content on Instagram reels. PLoS One. 2026;21(6):e0350430. PMID: 42308201.
38. ClinicalTrials.gov. Registrations of larazotide (AT-1001, INN-202): NCT00386490 (Phase 1, healthy volunteers, 24 enrolled, completed 2006), NCT00386165 (Phase 1b, 21, 2006), NCT00362856 (Phase 2a, 80, 2007), NCT00492960 (Phase 2b, 171, 2009), NCT00620451 (Phase 2b in active celiac disease, 105, 2009), NCT00889473 (Phase 2b, 42, 2010), NCT01396213 (Phase 2b, 342, 2013), NCT03569007 (Phase 3, 307, terminated July 21, 2022, “Trial terminated by Sponsor”), NCT05022303 (Phase 2a in MIS-C, 12, terminated May 15, 2024, “Decline in MISC cases”) and NCT05747534 (Phase 2a in Long COVID, 107, completed June 18, 2026). None posts results. clinicaltrials.gov, API v2. Read October 3, 2026.
39. 9 Meters Biopharma, Inc. 9 Meters Biopharma Announces Interim Analysis of Phase 3 Study of Larazotide for Celiac Disease Does Not Support Trial Continuation. Press release, June 21, 2022 (Form 8-K, Exhibit 99.1). sec.gov/Archives/edgar/data/1551986/000155198622000046/ex-991pressreleasedated621.htm. Read October 3, 2026.
40. 9 Meters Biopharma, Inc. Quarterly report (Form 10-Q) for the quarter ended June 30, 2022, filed August 15, 2022: the 2016 license from Alba Therapeutics, the decision announced August 15, 2022 to discontinue larazotide in celiac disease, and the EBRIS collaboration and April 2022 license for MIS-C. sec.gov/Archives/edgar/data/1551986/000155198622000091/nmtr-20220630.htm. Read October 3, 2026.
41. 9 Meters Biopharma, Inc. Current report (Form 8-K), filed July 18, 2023, Item 1.03: operations ceased and a voluntary Chapter 7 petition filed on July 17, 2023 (US Bankruptcy Court, Eastern District of North Carolina, case 23-01992-5-PWM). sec.gov/Archives/edgar/data/1551986/000093041323001864/c106716_8k-ixbrl.htm. Read October 3, 2026.
42. US Securities and Exchange Commission. EDGAR filer record, CIK 1551986: 9 Meters Biopharma, Inc., former name Innovate Biopharmaceuticals, Inc. (to May 2020). data.sec.gov/submissions/CIK0001551986.json. Read October 3, 2026.
43. FDA. Warning letter 320-26-24 (MARCS-CMS 716152), December 8, 2025, to a US distributor of active pharmaceutical ingredients: larazotide acetate among the ingredients distributed to compounders seeking to operate under section 503A that are “ineligible for use in human drug compounding under sections 503A.” fda.gov, Warning Letters. Read October 3, 2026.
44. FDA. National Drug Code Directory: bulk-ingredient listings NDC 73212-074 (“Larazotide,” powder, marketing start May 29, 2023) and 71052-096 (“Larazotide Acetate,” powder, marketing start January 13, 2026) (openFDA drug/ndc, data of October 2, 2026); and “About the NDC directory,” fda.gov/drugs/drug-approvals-and-databases/national-drug-code-directory. Read October 3, 2026.
45. FDA. Drugs@FDA through openFDA (api.fda.gov/drug/drugsfda.json): searches for larazotide and larazotide acetate, October 3, 2026 (no records). European Medicines Agency. Medicines data table (ema.europa.eu, medicines-output-medicines_json-report), searched for larazotide, October 3, 2026 (no entry).
46. Code of Federal Regulations. 21 CFR 216.23, Bulk drug substances that can be used to compound drug products in accordance with section 503A of the Federal Food, Drug, and Cosmetic Act. ecfr.gov (version of October 1, 2026). Read October 3, 2026.
47. FDA. Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act (categories 1–3). Updated May 14, 2026. fda.gov/media/94155/download.
48. FDA. Bulk Drug Substances Nominated for Use in Compounding Under Section 503B of the Federal Food, Drug, and Cosmetic Act (categories 1–3). Updated March 21, 2025. fda.gov/media/94164/download.
49. World Anti-Doping Agency. Prohibited List 2026 (in effect January 1, 2026). S0, Non-approved substances. wada-ama.org.
50. Searches of October 3, 2026: PubMed, “larazotide” (81 records; 11 about the nicotinic-receptor compound or migalastat, also coded AT-1001); PubMed and Europe PMC, larazotide with KPV, BPC-157, TB-500 or GHK-Cu (no study of a combination), with drug-interaction terms (no interaction study), toxicology terms (no toxicology study of larazotide) and pregnancy (no record); ClinicalTrials.gov, “larazotide,” “AT-1001,” “AT1001” and “INN-202” (ten larazotide registrations, none recruiting or active); NIH Dietary Supplement Label Database, “larazotide” (no labels); chemical-supplier catalogues listing larazotide and larazotide acetate powder for research use only (suppliers not named).

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