Healing & Recovery · 8 min read · Published September 8, 2026

Peptides for Gut Health: BPC-157, KPV and Larazotide Ranked by Human Evidence

Five peptides sold or studied for the gut, ranked by what has actually been tested in people: teduglutide (approved), larazotide (a positive Phase 2b, then a Phase 3 stopped for futility in 2022), BPC-157 and KPV (animal data only, advisory votes in July 2026) and pentadeca arginate (no studies at all).

Which gut peptides actually have human evidence?

Ranked by human data: teduglutide is FDA-approved for short bowel syndrome, based on a 24-week randomized trial of 86 patients published in 2012. Larazotide had a positive 342-adult Phase 2b in 2015, then a Phase 3 stopped for futility in June 2022. BPC-157 and KPV have animal data only. None of the last three is approved anywhere.

Regulatory status first, because it frames everything else. BPC-157, KPV, larazotide and pentadeca arginate are not approved drugs in the United States or anywhere else. On July 23, 2026 the FDA's Pharmacy Compounding Advisory Committee voted 8 to 6 in favor of adding BPC-157 and KPV to the 503A bulk-substances list, over the objection of FDA's own reviewers; that vote is advisory and nothing can be legally compounded until rulemaking finishes (our FDA status tracker has the documents). Teduglutide is the exception: an approved prescription drug with a narrow indication. This article ranks the five by the quality of human evidence, not by popularity.

How we tiered the evidence

• Human RCT: randomized, controlled, published with a pre-specified endpoint.
• Human pilot or observational: small uncontrolled series, retrospective chart reviews, cohorts.
• Animal: rodent or large-animal models of ulcer, colitis, anastomosis or barrier injury.
• In vitro: cell lines and tissue explants.
• None: no published study of the substance itself.

Did larazotide work for celiac disease?

Partly, then no. In the 2015 Phase 2b (342 adults on a gluten-free diet, 12 weeks of treatment), larazotide 0.5 mg three times daily reduced symptom scores versus placebo; the 1 mg and 2 mg doses did not. The Phase 3 CedLara trial (525 planned) was stopped for futility in June 2022 at its interim analysis.

Larazotide (AT-1001) is an oral eight-amino-acid peptide that acts locally in the gut as a zonulin antagonist, tightening the junctions between intestinal cells so that gluten fragments have a harder time crossing. It is the best-studied 'gut barrier' peptide by a wide margin. The Phase 2b, published in Gastroenterology in 2015 (Leffler et al., NCT01396213), met its primary endpoint on the Celiac Disease Gastrointestinal Symptom Rating Scale only at the lowest dose, with a 26 percent decrease in symptomatic days as an exploratory endpoint, and safety comparable to placebo (PubMed 25683116). Evidence tier: human RCT.

The Phase 3, CedLara (NCT03569007), started in May 2019 under 9 Meters Biopharma and tested 0.25 mg and 0.5 mg three times daily against placebo, with a 12-week primary endpoint on the abdominal domain of the CeD PRO questionnaire. On June 21, 2022, with roughly half of the planned 525 patients enrolled (307 by the registry's final count), an independent interim analysis concluded that the number of additional patients needed to show a significant difference was 'too large to support trial continuation', and the sponsor terminated the study (9 Meters press release, SEC filing). No efficacy result was reported, and we found no subsequent pivotal trial. Larazotide remains investigational.

Does BPC-157 heal the gut in humans?

Nobody knows. BPC-157 has a large rat literature: a 2007 Surgery Today study showed better small-bowel anastomosis healing over 14 days, and early Pliva colitis trials were never published. A 2025 systematic review found 35 preclinical studies and one human study, a retrospective series of 12 knee-pain patients. No human gut study exists.

BPC-157 is a 15-amino-acid fragment of a protein found in human gastric juice, and gut healing is where its research started. The Zagreb group led by Predrag Sikiric has published rat studies for more than 25 years showing protection against gastric ulcers, healing of colon and ileum anastomoses, and closure of fistulas. In the 2007 anastomosis study, BPC-157 given intraperitoneally at 10 micrograms or 10 nanograms per kilogram improved every measured healing parameter in rats over 14 days (PubMed 17713731). Evidence tier: animal. The same paper states that the peptide was 'shown to be safe in clinical trials for inflammatory bowel disease (PL-10, PLD-116, PL14736, Pliva, Croatia)'. Those trials are the closest BPC-157 has come to a human gut study, and no efficacy data from them has ever appeared in a journal.

The 2025 systematic review in HSS Journal searched the literature from 1993 to June 2024 and found 36 eligible studies: 35 preclinical and one clinical, a retrospective report in which 7 of 12 patients given an intra-articular injection for chronic knee pain reported relief lasting more than six months (PubMed 40756949). A separate 2025 narrative review counted three human pilot studies in total: the knee series, an interstitial cystitis study and an intravenous safety study (PubMed 40789979). Zero human gut studies. Evidence tier for gut use: animal. The FDA's July 2026 briefing document evaluated BPC-157 specifically for ulcerative colitis, weighed against adding it to the compounding list, and flagged immunogenicity concerns for injectable forms (FDA briefing document).

Pentadeca arginate is the same 15-amino-acid sequence as BPC-157 with an arginine counter-ion instead of acetate. It appeared after the 2023 Category 2 listing as a claimed legal alternative. There is no study of the arginate salt in any species. Evidence tier: none of its own; it inherits BPC-157's animal data at best.

What does KPV do for colitis?

In mice, a fair amount. In a 2008 Gastroenterology study, KPV added to drinking water reduced inflammation in both DSS- and TNBS-induced colitis, and nanomolar concentrations blocked NF-kB signaling in human intestinal cell lines via the PepT1 transporter. In humans, nothing: the FDA's 2026 review found no clinical studies, no pharmacokinetic data and no adverse-event reports for KPV.

KPV is the three-amino-acid tail of alpha-melanocyte-stimulating hormone (Lys-Pro-Val). The Dalmasso 2008 paper is the study everyone cites, and it is a good one: it showed that KPV is carried into intestinal epithelial and immune cells by the PepT1 transporter, that it dampens NF-kB and MAP-kinase inflammatory signaling in Caco2 and Jurkat cells, and that oral KPV reduced histologic inflammation and pro-inflammatory cytokine expression in two mouse colitis models (PubMed 18061177). Evidence tier: animal and in vitro.

That is where the trail ends. KPV was nominated to the FDA for 'wound healing and inflammatory conditions' as a cream or gel. FDA reviewers wrote that they 'did not identify data, such as clinical studies, on the use of KPV in humans', found no human pharmacokinetic data, no case reports and no reports in the FAERS adverse-event database through December 3, 2025, and concluded that the criteria weighed against listing (FDA KPV briefing document). The committee voted 8 to 6 the other way. For a sense of what a regulated gut-inflammation peptide program looks like, PL8177, an oral melanocortin-1 receptor agonist, reached a Phase 2 in ulcerative colitis; it is small and unfinished, but it is a trial.

Which gut peptides are FDA-approved?

Teduglutide (Gattex), a GLP-2 analogue, is approved for short bowel syndrome with intestinal failure. In the 24-week STEPS trial (Gastroenterology, 2012; 43 patients per arm, 0.05 mg/kg daily), 63 percent of teduglutide patients cut parenteral support by more than 20 percent versus 30 percent on placebo. It is a hospital-level drug for a rare condition, not a gut-health supplement.

Teduglutide matters here as the calibration point. It is a GLP-2 analogue that grows intestinal mucosa, approved by the FDA on December 21, 2012 (NDA 203441), and the STEPS trial showed a mean reduction in parenteral support of 4.4 liters per week versus 2.3 on placebo at week 24 (PubMed 22982184). Evidence tier: human RCT. It carries warnings about intestinal polyps and obstruction, which is a reminder that a peptide powerful enough to change gut tissue is powerful enough to need monitoring.

The bottom line

If the question is 'which gut peptide has been shown to work in people', the honest ranking is short: teduglutide for one rare disease, larazotide for celiac symptoms in one mid-sized trial that its own Phase 3 could not confirm, and then a cliff. BPC-157's rat data are real and consistent, and they are still rat data. KPV's colitis data are from 2008 and from mice. The July 2026 votes changed a regulatory conversation, not the evidence. For side-effect signals by peptide class, see peptide side effects by class, and for what a vial's certificate of analysis can and cannot tell you, see how to read a peptide COA.