Of the four compounds people search for here, the one with the most published human evidence is teduglutide. It is a manufactured copy of GLP-2, the hormone your own gut releases after a meal to rebuild its lining, and it is an approved prescription medicine for one narrow bowel condition. BPC-157, the compound sold hardest online for gut complaints, is the only one of the four that a drug company took into human inflammatory bowel disease trials, and no phase 2 result has been published in the twenty years since. In July 2026 an FDA advisory committee voted 8 to 6 with one abstention to recommend BPC-157 for pharmacy compounding on an ulcerative colitis nomination, after the agency's own scientists told the room that the effectiveness evidence for that use was not there. The vote was a recommendation only: as of 23 September 2026 BPC-157 is still not on the list of substances compounding pharmacies may use, and it is not approved for human use in the United States.
Sort these four by how loudly they are sold for gut problems and you get one order. Sort them by what a human development programme did with each one and you get very nearly the reverse. The compound with the quietest marketing, teduglutide, is a licensed medicine. The loudest, BPC-157, is the only one of the four a drug company ever took into human inflammatory bowel disease trials, in Croatia, under the development name PL 14736, which almost nobody selling it today could tell you. Then the programme stopped, and in twenty years nothing was published. (New to any of this? Start with the beginners' guide and come back.)
Which of these four finished a human gut programme?
One of the four finished. GLP-2 analogues went through human trials and became prescription medicines. BPC-157 started a human inflammatory bowel disease programme and stopped. KPV and LL-37 were never taken into a human gut trial at all. The table below sorts them by what a development programme did with each one.
| Compound | What a human gut programme did with it | How far it got | What was published | Read more |
|---|---|---|---|---|
| GLP-2 analogues (teduglutide, apraglutide) | Developed as prescription medicines for short bowel syndrome, a condition where so much bowel has been lost or removed that people need feeding through a vein | All the way to approval, and the class is still moving: a phase 3 trial of apraglutide published on 3 September 2026 | Randomised placebo-controlled trials, plus a 2026 pooled analysis of 23 studies 12 | GLP-2 and gut healing |
| BPC-157 | Taken into human inflammatory bowel disease trials in Croatia by the drug company Pliva, under the development name PL 14736 | The developers' own review says phase 2. An independent 2026 review that searched the literature, the patent databases and the regulators found no completed phase 2 34 | No phase 2 result anywhere in twenty years. Published human exposure is fewer than 30 people across three uncontrolled pilots 35 | How BPC-157 works |
| KPV | Never given to a person for a gut condition in a published trial | Human cell lines and early colitis research only; nothing in people | Mechanism work from 2008 onward, plus later delivery-platform papers 6 | KPV |
| LL-37 | Not developed as a gut drug | No human gut programme to report | Nothing for a gut indication | LL-37 |
LL-37 is on this list only because it travels in blends sold for gut complaints. It is an antimicrobial peptide your own body makes, and nobody has run it as a gut treatment. The compound page has the detail.
That order is the development record, not advice on what to take. It says which programmes produced published human results, which is a different question from which compound suits a given person, and the second question belongs with a clinician who knows the diagnosis.
What happened to BPC-157's gut programme?
BPC-157 was taken into human inflammatory bowel disease trials by Pliva, a drug company in Croatia, under the development name PL 14736. The programme reached what its developers describe as phase 2, the stage at which a drug is first tested for effectiveness in patients and not only for safety, and then it stopped. No phase 2 result has been published anywhere in the twenty years since.
The phase 2 claim itself comes from the developers' own 2012 review, titled around ulcerative colitis, which states that the compound was "so far only tested in clinical phase II" 4. That is an interested source, which does not make it false, and it is the only place the claim appears. An independent review published in Pharmaceutics in May 2026 went looking: it searched PubMed and MEDLINE, Embase and the Cochrane Library from inception to April 2026, plus Espacenet, Google Patents and the FDA, EMA and WADA websites, and reported that BPC-157 has "no approved formulation, no validated dosing regimen, and no completed Phase II clinical trial" 3. Both statements are on the public record, and this page does not resolve them. The disagreement is itself the finding worth carrying.
What is not in tension is the size of the human record. The same 2026 review reports that all available clinical data on BPC-157 "derive from fewer than 30 subjects across three uncontrolled pilot studies, none of which employed standardized pharmaceutical preparations" 3. The entire published intravenous record is two people, a 58-year-old man and a 68-year-old woman, given 10 mg and then 20 mg under observation for safety alone, with no effectiveness endpoint measured 5.
The primary barrier to clinical translation is not the absence of biological activity, but the absence of fundamental pharmaceutical science.Mateescu DM and colleagues, Pharmaceutics, May 2026
A compound that was taken into human trials and then dropped with nothing published is weaker evidence than one that was never tried. The silence is informative.
What the FDA advisory committee decided about BPC-157 in July 2026
On 23 July 2026 the Pharmacy Compounding Advisory Committee met to consider whether BPC-157 should be added to the 503A bulks list, the list of raw substances a compounding pharmacy is allowed to make medicines from. The indication on the nomination was ulcerative colitis, a chronic inflammation and ulceration of the large bowel. That room argued the question a gut-peptide search is asking: does BPC-157 do anything for an inflamed bowel.
Ahead of the meeting, FDA staff posted a scientific review recommending against adding these peptides on both safety and effectiveness grounds, and the briefing package said there is a "lack of evidence to support the effectiveness of BPC-157 (free base) and BPC-157 acetate as a treatment for ulcerative colitis" 7. In the room, the agency's own scientists were blunter. Russell Wesdyk of the FDA opened by asking "What is BPC-157?", noted that people disagree about what the substance even is, and said the agency cannot set quality standards for it until more is known. A second FDA scientist, Mai Tu, said the peptide is "not well-characterized" 7.
We cannot establish quality standards until more is known about the substance.
The committee recommended adding it anyway, 8 votes to 6 with one abstention 7. Members on both sides are named in the record. Elizabeth Rebello of MD Anderson pointed to the "lack of efficacy data and randomized controlled trials", and Bill Zamboni said "There are too many unknowns about this product". David Pope of XiFin Pharmacy Solutions voted yes and said it was "time to put this decision back in the hands of the physician and pharmacist" 7.
Two facts belong beside that vote. In June 2026 the FDA added eight new members to that committee, several with reported ties to prescribing or promoting peptides, and the Secretary of Health and Human Services, Robert F. Kennedy Jr, has publicly called himself a "big fan" of peptides 7.
KPV was recommended by the same committee at the same meeting, by the same 8 to 6 vote, but its nomination was for wound treatment and inflammatory conditions, not for anything in the gut 7. Nobody asked that committee whether KPV works for a bowel disease, because there is no human evidence to ask about.
Is BPC-157 legal to get from a compounding pharmacy in 2026?
No, and the advisory vote did not change that. On 15 April 2026 the FDA announced that seven peptides, BPC-157 and KPV among them, would come off 503A Category 2, the restricted list that had effectively stopped compounding pharmacies working with them, after seven calendar days. The stated reason was that the nominations behind those substances had been withdrawn 8. A Federal Register notice the following day, 16 April 2026, announced the public meeting that became the July hearing. Removal from Category 2 "does not, on its own, authorize use of that substance in compounding" 8. Getting onto the 503A bulks list happens through notice-and-comment rulemaking, a formal process with a published proposal and a public comment period, and as of 23 September 2026 none of the seven is on that list, because the July vote was a recommendation and nothing more 78. Our running tracker of US peptide legality follows where this goes next; check that page for the current position, because the dates keep moving.
What the 64 percent figure behind teduglutide is measuring
A systematic review and meta-analysis of GLP-2 analogues in intestinal failure, published in Clinical Nutrition ESPEN in February 2026 by a team at Austin Health in Melbourne, pooled 23 studies and reported that 64 percent of patients on teduglutide reached the main endpoint at six months (95% confidence interval 51 to 75), rising to 73 percent after two or more years (95% CI 65 to 80) 1. That endpoint counts a reduction of at least 20 percent in parenteral support, the nutrition delivered through a vein to people whose bowel cannot absorb enough on its own. A fifth less time attached to a drip is a genuine gain for someone living that way, and it is a different outcome from being free of the drip. Being free of it has its own number in the same analysis, and it is much smaller: 13 percent at six months, 31 percent after two or more years 1. Fourteen percent of patients stopped the therapy. Those two sets of figures get flattened into a single trend across the internet, and they are not one trend. Our GLP-2 page carries the trials themselves.
The class has not stopped moving. A phase 3 trial of once-weekly apraglutide, published on 3 September 2026, randomised 163 patients 2 to 1 against placebo and reported weekly parenteral support volume falling 25.5 percent from baseline against 12.5 percent on placebo at week 24, a gap unlikely to be chance (P = .001) 2. Two caveats travel with that result and belong next to it: the week 48 endpoint for needing no feeding through a vein at all, measured in the colon-in-continuity subgroup and not in the whole trial, was 12.5 percent against 7.4 percent and did not reach statistical significance (nominal P = .387), and several of the authors are employees of the sponsor, Ironwood Pharmaceuticals 2.
Teduglutide is approved for short bowel syndrome, a specialist-managed condition and not a description of a difficult digestion, and it reaches patients through a prescription and a specialty pharmacy. The GLP-2 compound page carries the reference detail. Your own gut makes GLP-2 too, and what raises it is a separate story with a lever in it that needs no prescription.
Has KPV ever been given to a person for a gut condition?
No published trial has given KPV to a person for any gut condition. That is the honest headline for KPV, and it should sit in front of everything else written about it.
What exists is mechanism work. KPV is a three-amino-acid fragment of alpha-MSH, a hormone that damps down inflammation. A 2008 paper in Gastroenterology showed that KPV gets into gut lining cells and immune cells through PepT1, a transporter those cells already use to pull small protein fragments out of food. At nanomolar concentrations, meaning very low ones, it blocked NF-kB, the master switch that turns inflammatory genes on, and reduced the release of inflammatory signalling proteins. Given by mouth in drinking water in early research, it reduced two chemically induced forms of colitis 6. None of that work was done in people, and it is the whole of the case. Any percentage you see quoted for how much KPV reduces inflammation in a human gut has no source behind it.
KPV enters cells through PepT1, the transporter the gut already uses for food-derived peptide fragments, and that early research dosed it by mouth, which is why it turns up in capsules and in blends. Transport into a cell is not the same as surviving digestion, and no human study has measured how much of a swallowed dose reaches anywhere. Later work built nanoparticle delivery platforms around KPV, including one that carried it together with teduglutide, and those papers describe a delivery platform that holds promise, not a combination therapy shown to work in anyone. The named blend that carries KPV is the KLOW stack, and whether combining compounds is a good idea at all is its own question.
BPC-157 and KPV for gut problems, side by side
Stomach-acid stability, and the half-life problem behind it
Swallowing a peptide is usually close to pointless, because digestion takes it apart before it reaches the bloodstream. Gut compounds are the exception, for a reason that is easy to state and easy to over-read. Our swallow-or-inject page puts it this way: "BPC-157 genuinely survives stomach acid for over 24 hours in the lab. Whether any of it then crosses into your bloodstream has never been measured in a human."
That stability is real, and the 2026 review confirms it 3. The same review then reports the problem that follows. BPC-157's plasma half-life, the time it takes for half of a dose to clear the bloodstream, is under 30 minutes, confirmed both in a formal preclinical absorption study and in the two-person human pilot, while the biological effects attributed to the compound last hours to days. The review calls that disconnect a significant problem for anyone trying to design a dose, and reports that bioavailability from an injection into muscle ranged from 14 to 51 percent depending on the species measured 3. A compound whose exposure nobody can pin down is a compound whose dose nobody can pin down.
We print no dose. Our BPC-157 dosing guide covers what circulates and where those figures came from, and its own summary of the situation is blunt: "There is no human dose-finding study." How BPC-157 works covers the mechanism claims in detail.
What is actually in the vial you would be buying?
Teduglutide is a branded prescription medicine, dosed by body weight and dispensed through a specialty pharmacy, and for its approved indication the cost question is usually an insurance question and not a price tag. BPC-157, KPV and LL-37 are sold as research chemicals, labelled for laboratory use and not for human consumption, and no vendor of them is selling an approved medicine. Nobody has verified the contents of those vials against a pharmacy-grade standard, and the 2026 review's finding of no pharmaceutical-grade formulation applies to every one of them 3. Vendors generally instruct that the powder be kept cold and used within weeks of being mixed, but none of these products carries the stability specification a licensed medicine has to earn, so those instructions rest on nothing anyone has verified.
An analysis posted in April 2026 examined 6,441 grey-market peptide samples across fourteen compounds, including BPC-157 and TB-500, and applied two quality frameworks: one approximating the standards for compounded medicines, and a stricter one closer to the standards applied to FDA-approved peptide drugs. Between 41.6 and 71.1 percent of samples failed basic quality criteria, depending on which framework was used, and measurable endotoxin was present in 15 percent of the samples tested for it. It is a preprint and not a peer-reviewed paper, which is worth saying on a page about the difference between evidence that finished and evidence that did not 11.
Endotoxin is a fragment of bacterial cell wall that triggers fever and a strong inflammatory response when it gets into the bloodstream, which is an unfortunate outcome for anyone injecting a product to calm inflammation down. We are not recommending that anyone buy any of this. Our gut healing guide covers what to rule out before spending money, along with the monitoring and contraindication questions that follow. On the compounds sold grey-market it lands where this page lands: no published human trial stands behind any of them.
Why results differ so much between people, in order of importance
Two people run the same gut compound and one says it changed their life while the other says nothing happened. Genetics sits near the bottom of the list of reasons, and the things above it are ordinary and checkable.
- Whether the thing damaging the gut is still there. Continuing anti-inflammatory painkillers, heavy drinking, an untreated infection or an unaddressed food trigger will outpace anything added on top.
- What the actual diagnosis is. Ulcerative colitis, coeliac disease, bacterial overgrowth in the small bowel and a functional bowel disorder are different problems with different treatments, and "leaky gut" describes a lab measurement without naming a diagnosis.
- What was in the bottle, given that between 42 and 71 percent of grey-market samples failed basic quality checks 11.
- How long it was given, and against what baseline. Published work measured outcomes over weeks and months, and one good week is not a result.
- How much gut symptoms move on their own. Bloating, urgency and discomfort after eating swing week to week for reasons nobody is tracking, which makes this the area where people fool themselves most easily.
Then, some way down that list, genetics. The Dutch Microbiome Project analysed 7,738 people across 207 bacterial groups and 205 functional pathways, and only two signals reached study-wide significance: one near LCT and one near ABO, both replicated in two independent cohorts. The ABO associations could be explained by participants' secretor status, which is set by a gene called FUT2 and decides whether you coat your gut lining and other secretions with a particular sugar that many gut bacteria feed on and cling to 9. So secretor status sits behind one of those two signals instead of being one of them. It is still the most solid host-genetics finding about gut bacterial composition, and it is still silent on which peptide anyone should buy, because no published trial has sorted responders from non-responders by genotype for any of these four compounds.
The gene that would matter mechanically for KPV is the one that makes the transporter it rides in on, SLC15A1. A study of 1,783 people found its coding variant associated with Crohn's disease risk in opposite directions in Sweden and Finland 10. So the single gene with a direct mechanical link to a compound on this page has never been tested against that compound, and two cohorts could not agree on which way it pointed even for disease risk. Neither SLC15A1 nor TLR4, the bacterial-toxin sensor people often assume is involved, is on the PeptidesDNA panel.
| Compound | What a PeptidesDNA report weights toward it |
|---|---|
| KPV | An inflammation set-point cluster of eight variants: TNF, IL1B, IL6, IL10, NLRP3, CRP, PTGS2 and FUT2 |
| GLP-2 | Secretor status and two inflammation markers |
| LL-37 | The vitamin D axis, because the body makes its own LL-37 through a step that depends on vitamin D |
| BPC-157 | Connective-tissue markers, and not one gut marker among them |
Those markers describe how loudly your inflammation system tends to run and what ground your gut is starting from. They do not predict response. Our own database note on the collagen variant behind the BPC-157 set reads that the association "is contested and does NOT predict response to BPC-157", and that is the honest line. If inflammation and not the gut specifically is the thing you are chasing, that has its own page. How much of this sits in a 23andMe or AncestryDNA file depends on your chip version.
Where to go from here
- Peptides for gut healing for the condition itself: what to rule out first, monitoring, contraindications and how the compounds are used in practice.
- BPC-157 for the compound reference, and how BPC-157 works for the mechanism claims examined one at a time.
- Gut peptides and liver protection for what leaks past a damaged lining and where it ends up.
- Best peptides for healing if the question is soft tissue and wounds and not the gut.
Curious how your genetics shape the ground your gut is starting from? Upload the raw DNA file you already have and get all 39 peptides ranked for you, with the inflammation and barrier markers behind each ranking spelled out rather than hidden. A human reviews every report before it goes out, within 24 hours.
Get your DNA report- An abandoned programme is weaker evidence than an untried one
BPC-157 reached human inflammatory bowel disease trials in Croatia as PL 14736 and nothing was published in the twenty years since. A compound that was tried in people and then dropped in silence is a worse bet than one nobody has tried yet, because the silence carries information the marketing never mentions.
Sources11
- Bastas A, Williams K, Wong D. Positive clinical outcomes associated with use of glucagon-like peptide-2 (GLP-2) analogues in patients with intestinal failure: a systematic review and meta-analysis. Clinical Nutrition ESPEN. 2026 Feb;71:102817.
- Joly F et al., STARS Investigators. STARS phase 3 trial: once-weekly apraglutide reduces parenteral support in short bowel syndrome with intestinal failure. Clinical Gastroenterology and Hepatology. Published online 3 September 2026. Week 48 enteral autonomy was a colon-in-continuity subgroup endpoint (12.5% vs 7.4%, nominal P = .387).
- Mateescu DM et al. BPC-157 as an investigational peptide therapeutic: biopharmaceutical challenges, formulation strategies, and translational development barriers. Pharmaceutics. 2026 May 20;18(5):625.
- Sikiric P et al. Focus on ulcerative colitis: stable gastric pentadecapeptide BPC 157. Current Medicinal Chemistry. 2012;19(1):126-32. The developers' own review and the origin of the phase 2 claim, cited here as an interested source.
- Lee E, Burgess K. Safety of intravenous infusion of BPC157 in humans: a pilot study. Alternative Therapies in Health and Medicine. 2025 Sep;31(5):20-24. Two participants, safety observation only, no effectiveness endpoint.
- Dalmasso G et al. PepT1-mediated tripeptide KPV uptake reduces intestinal inflammation. Gastroenterology. 2008 Jan;134(1):166-78. Human cell lines plus DSS- and TNBS-induced colitis in mice, KPV given in drinking water.
- Eglovitch JS. FDA advisory committee backs two controversial peptides. RAPS Regulatory Focus, 23 July 2026. Source of the FDA staff quotations, the 8 to 6 vote with one abstention, the named committee members and the three adverse event reports.
- Landmon CA, Davies C, Pape SM, Bassett SE, McCann JD. Tiny chains, big changes: what FDA's latest actions mean for peptide compounding. National Law Review. Source of the 15 April 2026 Category 2 removal on withdrawn nominations, the statement that removal does not authorize compounding, and the notice-and-comment rulemaking requirement for the 503A bulks list.
- Lopera-Maya EA et al. Effect of host genetics on the gut microbiome in 7,738 participants of the Dutch Microbiome Project. Nature Genetics. 2022 Feb;54(2):143-51. The two study-wide significant signals were near LCT and ABO; the ABO associations could be explained by participant secretor status determined by FUT2 genotype.
- Zucchelli M et al. PepT1 oligopeptide transporter (SLC15A1) gene polymorphism in inflammatory bowel disease. Inflammatory Bowel Diseases. 2009 Oct;15(10):1562-9. 1,783 individuals across Swedish and Finnish cohorts; the rs2297322 C allele associated with Crohn's disease in opposite directions in the two populations.
- Mendias CL, Awan TM. Evaluation of research grade peptides marketed directly to consumers reveals extensive variability in purity and measured abundance. Preprints.org, posted 24 April 2026. A preprint, not peer reviewed. 6,441 samples across fourteen compounds; 41.6% to 71.1% failed quality criteria depending on which of two acceptance frameworks was applied; measurable endotoxin in 15% of samples tested.
This article is for informational and educational purposes only. It is not medical advice and does not diagnose, treat, cure, or prevent any disease. Consult a qualified healthcare professional before starting any peptide protocol. Individual results vary. Some outbound links are affiliate links, at no extra cost to you.
Frequently asked questions
Does KPV actually work for leaky gut?
Nobody knows, because no published trial has given KPV to a person for any gut condition, including increased intestinal permeability. What exists is mechanism work: KPV enters gut lining and immune cells through a transporter those cells use for food fragments, and at very low concentrations it blocked NF-kB, the master switch for inflammatory genes, and reduced inflammatory signalling. Given by mouth in drinking water in early research, it reduced two chemically induced forms of colitis. None of that work was done in people, and it is the whole of the case. Any specific percentage quoted for how much KPV reduces inflammation in a human gut has no source behind it.
What is the difference between BPC-157 and KPV for gut healing?
The research on them points at different jobs. KPV research targets inflammatory signalling inside gut lining and immune cells, while BPC-157 research targets tissue repair and the nerve network in the gut wall. The difference that matters more is the development record: BPC-157 was taken into human inflammatory bowel disease trials in Croatia and the programme stopped without publishing a result, while KPV has never been given to a person for a gut condition at all. Neither has a completed human gut trial, and neither is approved for human use in the United States.
Is GLP-2 the same as semaglutide or Ozempic?
No. Semaglutide, sold as Ozempic and Wegovy, copies GLP-1, a hormone that lowers blood sugar and reduces appetite. Teduglutide copies GLP-2, a different hormone released by the same gut cells at the same moment, which acts on the bowel wall to rebuild lining instead of acting on appetite. GLP-2 analogues are approved for short bowel syndrome, where so much bowel has been lost that people need feeding through a vein, and they do not cause weight loss.
Which gut health peptide should I start with?
The first step is finding out what is damaging the gut, because a lining cannot outheal an ongoing injury, and several of the conditions that get labelled leaky gut have actual treatments that work. Of the four compounds on this page, only GLP-2 analogues have completed human trials, and they are prescription medicines for a narrow condition, not something to try. BPC-157, KPV and LL-37 are not approved for human use in the United States and none of them is on the list of substances compounding pharmacies may use. Take the question to a clinician who can order the tests that separate those conditions.
This article is for informational and educational purposes only. It is not medical advice and does not diagnose, treat, cure, or prevent any disease. Consult a qualified healthcare professional before starting any peptide protocol. Individual results vary. Some outbound links are affiliate links, at no extra cost to you.