Informational only. Not medical advice.INFORMATIONAL PLATFORM ONLY — NOT MEDICAL ADVICE, DIAGNOSIS, OR TREATMENT
Informational only. Not medical advice.INFORMATIONAL PLATFORM ONLY — NOT MEDICAL ADVICE, DIAGNOSIS, OR TREATMENT
Head-to-head comparison of Larazotide and PEG-MGF — mechanism, dosing, side effects, legal status, and pricing.
Larazotide is a synthetic linear octapeptide (Gly-Gly-Val-Leu-Val-Gln-Pro-Gly) structurally derived from the Vibrio cholerae zonula occludens toxin. It is proposed to act on the zonulin/tight-junction signaling pathway, interrupting gliadin-triggered intestinal barrier disruption by preserving tight-junction integrity locally in the gut lumen. Larazotide has been studied in multiple human trials for celiac disease under the development codes AT-1001, INN-202, and SPD550, but has never received FDA or EMA approval; a Phase 3 trial (NCT03569007) was terminated by the sponsor in 2022 with no results posted. It is not systemically absorbed and is available only as a research chemical.
PEG-MGF is the pegylated form of Mechano Growth Factor (MGF), the distinct 24-amino-acid C-terminal E-peptide encoded by the IGF-1Ec splice variant (IGF-1Eb in rodents) that is transiently upregulated in muscle after mechanical loading or damage. MGF is related to but pharmacologically distinct from mature IGF-1 and IGF-1 LR3. Pegylation extends its half-life from minutes to several hours, and the compound is marketed as a research chemical for muscle repair protocols. It is not FDA-approved for any indication.
Larazotide
PEG-MGF
Category
Legal Status
Mechanism
Dose Range
COA-verified vendors · trust score ≥70 required · single-vial price — bulk/bundle deals may be lower
Larazotide
PEG-MGF
COA corpus from Disclosed Labs — independently tested batches only.
Larazotide
1
COAs
98.3%
Avg purity
1
Labs
PEG-MGF
12
COAs
99.6%
Avg purity
5
Labs
Larazotide has been studied in multiple completed human trials for celiac disease but has never received FDA or EMA approval. A Phase 1 single-dose study (Paterson et al. 2007, PMID 17697209) confirmed no systemic absorption. Phase 2 gluten-challenge trials (Leffler et al. 2012, PMID 22825365, n=86, doses 0.25/1/4/8 mg TID) did not meet the primary endpoint (intestinal permeability) due to high variability, though lower doses limited symptom worsening. A Phase 2b trial (Leffler et al. 2015, PMID 25683116, ~342 patients, no gluten challenge) met its primary endpoint at the 0.5 mg TID dose, showing symptom improvement versus placebo with an inverse dose-response. The Phase 3 CeDLara trial (NCT03569007, 307 patients, 0.25 mg and 0.5 mg TID) was terminated by the sponsor in 2022 for futility/impractically large required sample size, with no results posted. Across trials, no serious drug-related adverse events or hepatic/renal/bone toxicity signals were reported; headache and urinary tract infection were the most common adverse events without consistent excess versus placebo. In preclinical models, larazotide reduced gliadin-induced paracellular permeability and preserved tight-junction protein localization in Caco-2 human intestinal cell monolayers, prevented gliadin-induced permeability increases and reduced macrophage infiltration in HLA-DQ8 transgenic mice, and accelerated barrier recovery in a porcine jejunum ischemia-reperfusion injury model.
Key references
Yang and Goldspink (FEBS Lett 2002, PMID 12095637) established that the MGF E-peptide promotes myoblast proliferation and delays terminal differentiation through a receptor distinct from IGF-1R, separating MGF pharmacology from mature IGF-1. Kandalla et al. (Mech Ageing Dev 2011, PMID 21354439) showed the 24-aa MGF E-peptide activates human muscle progenitor cells and enhances their fusion potential even from older donors. Qin et al. (Mol Cell Biochem 2012, PMID 22875667) confirmed MGF drives satellite-cell proliferation while inhibiting differentiation by down-regulating MyoD and p21. Comprehensive reviews by Matheny, Nindl & Adamo (Endocrinology 2010, PMID 20130113) and Zabłocka, Goldspink et al. (Front Endocrinol 2012, PMID 23125840) summarize the evidence across muscle, cardiac and neural tissue and caution that MGF's receptor, in vivo pharmacokinetics, and safety profile remain incompletely characterized. No randomized controlled human trials of PEG-MGF have been published. MGF and IGF-1 analogs are prohibited at all times under the WADA Code.
Larazotide (Immune) and PEG-MGF (Performance) are in different categories and target different biological pathways. This is a common pattern in multi-compound research protocols. Researchers should monitor the biomarkers from both profiles and watch for interactions listed in each compound’s contraindications. Consult a licensed healthcare provider before combining any research compounds.
This platform provides informational tools only, not medical advice. This comparison is for educational purposes only. Consult a licensed provider.
Route
Frequency
Dosing Notes
Half-life
Side Effects
Contraindications
Lab Testing
Key references
Disclosed Labs