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 IGF-1 LR3 and Tesamorelin — mechanism, side effects, legal status, and pricing.
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.
Tesamorelin (Egrifta / Egrifta SV) is a stabilized analog of human GHRH(1-44) with a trans-3-hexenoic acid moiety at the N-terminus that protects against protease degradation. FDA-approved in November 2010 for the reduction of excess abdominal fat in HIV-infected patients with lipodystrophy, it is the only FDA-approved GHRH analog for this indication. Off-label use for general body composition and visceral fat reduction in non-HIV populations is common but outside the approved label.
IGF-1 LR3
Tesamorelin
Category
Legal Status
Mechanism
Half-life
Side Effects
COA-verified vendors · trust score ≥70 required · single-vial price — bulk/bundle deals may be lower
IGF-1 LR3
Tesamorelin
COA corpus from Disclosed Labs — independently tested batches only.
IGF-1 LR3
42
COAs
98.7%
Avg purity
9
Labs
Tesamorelin
175
COAs
99.5%
Avg purity
14
Labs
Tesamorelin is among peptides under FDA review for the Category 1 (503A) list; if added, it would require a prescription to be compounded by registered 503A/503B pharmacies — not yet authorized. IGF-1 LR3 remains research-only. In April 2026 the FDA removed 12 peptides from Category 2, which does not place them on the Category 1 list or authorize compounding. The FDA's Pharmacy Compounding Advisory Committee is advisory and meets July 23–24, 2026 to review nominations and make recommendations to the FDA.
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.
Key references
FDA approval (NDA 022505) was based on two Phase 3 trials reported by Falutz et al. (NEJM, 2007; PMID 18057338) and the pooled 52-week safety extension, showing ~15-18% reduction in visceral adipose tissue with improved triglycerides in HIV patients with abdominal fat accumulation. Stanley et al. (JAMA, 2014; PMID 25038357) demonstrated concurrent reductions in visceral and liver fat (NAFLD). Baker et al. (Arch Neurol, 2012; PMID 22869065) reported favorable effects on executive function in older adults with and without mild cognitive impairment at 1 mg/day for 20 weeks — note this cognition signal was in MCI / healthy older adults, not specifically APOE4-positive individuals. Current label dose is 1.4 mg SubQ daily (Egrifta SV); legacy Egrifta used 2 mg/day. Off-label use for general body composition in non-HIV populations is common but outside the FDA label.
IGF-1 LR3 and Tesamorelin are both in the Performance category and may have overlapping mechanisms. Researchers should review both profiles carefully, understand the mechanisms of action, and monitor the relevant biomarkers when combining compounds in the same class. As always, consult a licensed healthcare provider before making any decisions about combining 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