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 Capromorelin and IGF-1 LR3 — mechanism, side effects, legal status, and pricing.
Capromorelin is a non-peptide, orally active pyrazolinone-piperidine dipeptide-mimetic that functions as a growth hormone secretagogue receptor 1a (GHS-R1a) agonist, mimicking the endogenous hormone ghrelin. It is NOT approved for human use anywhere; a Pfizer Phase II trial in 395 older adults showed positive signals for lean body mass, body weight, and physical function but was terminated early and never advanced to approval. Capromorelin is FDA-approved as a veterinary drug (Entyce for dogs, Elura for cats) and is explicitly named on the WADA Prohibited List under S2 (growth hormone secretagogues), prohibited at all times in competitive sport.
IGF-1 LR3 is an 83-amino-acid modified IGF-1 analog with a 13-residue N-terminal extension (MFPAMPLSSLFVN) and an Arg-3 substitution. These modifications reduce binding to IGF binding proteins (IGFBPs), extending effective half-life and increasing tissue bioavailability relative to native IGF-1. It is a research/cell-culture reagent and is NOT FDA-approved for any human use. Do not confuse with mecasermin (Increlex), which is recombinant human IGF-1 and IS FDA-approved for severe primary IGF-1 deficiency.
Capromorelin
IGF-1 LR3
Category
Legal Status
Mechanism
Half-life
Side Effects
COA-verified vendors · trust score ≥70 required · single-vial price — bulk/bundle deals may be lower
Capromorelin
IGF-1 LR3
COA corpus from Disclosed Labs — independently tested batches only.
Capromorelin
No COA data yet.
Submit testing data →IGF-1 LR3
42
COAs
98.7%
Avg purity
9
Labs
Capromorelin has human clinical trial data but is not an approved human drug. A Pfizer-sponsored Phase II trial randomized 395 adults aged 65–84 at risk of functional decline to oral capromorelin or placebo for up to 2 years (315 completed 6 months; 284 completed 12 months). The trial reported increased lean body mass (+1.4 vs 0.3 kg, P=0.001), body weight (+1.4 kg, P=0.006), improved tandem walk (P=0.02), and improved stair climb (P=0.04), concluding capromorelin "may improve body composition and physical function." The study was terminated early according to predetermined treatment effect criteria; no human product was ever approved. Preclinical studies in rats showed an ED50 <0.05 mg/kg IV for plasma GH elevation; in healthy Beagle dogs, oral capromorelin increased food consumption and body weight in a 4-day randomized, masked, placebo-controlled trial. In healthy cats, capromorelin altered glucose-metabolism parameters. In broiler chickens, it increased feed intake and body-weight gain.
Key references
Francis et al. (J Mol Endocrinol 1992; PMID 1378742) characterized LR3-IGF-1 as a fusion analog whose enhanced biological potency derives from reduced IGFBP binding; in IGFBP-free cell systems LR3 was actually LESS potent than native IGF-1, underscoring that the 'potency' is really reduced sequestration rather than intrinsically stronger receptor activation. Tomas (Growth Horm IGF Res 2001; PMID 11472075) infused LR(3)IGF-I into food-restricted rats and found it preserved body weight and nitrogen retention but did NOT conserve skeletal muscle protein — which contradicts the common 'potent muscle builder' framing from preclinical literature alone. There are no controlled human trials supporting bodybuilding use. Epidemiologic and mechanistic work reviewed by Grimberg (Cancer Biol Ther 2003; PMID 14688466) links elevated IGF-1 axis activity to breast, prostate, and colorectal cancer risk, so chronic systemic LR3 exposure carries a concrete — not merely theoretical — tumorigenesis concern. IGF-1 and its analogs are banned at all times under the WADA Code.
Capromorelin (Hormone) and IGF-1 LR3 (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.
Contraindications
Lab Testing
Key references
Disclosed Labs