IGF-1 LR3
Long-acting IGF-1 analogue with reduced IGFBP binding; half-life ~20 hours vs ~10 min for native IGF-1. Studied for satellite cell activation, skeletal muscle hypertrophy, and mTOR pathway research. Limited US availability — verify stock before ordering.
What Research Shows
Studied for PI3K/Akt/mTOR-mediated protein synthesis, satellite cell (Pax7+) proliferation, and skeletal muscle hypertrophy via IGFBP-independent receptor engagement. Studies measure fibre cross-sectional area (immunofluorescence), p70S6K phosphorylation, and lean body mass by DXA. Strong mechanistic evidence; availability limited.
Pros & Cons
- +IGF-1 LR3 half-life of ~20 hours vs ~10 minutes for native IGF-1 — practical for in vivo dosing without continuous infusion
- +Directly engages mTOR pathway — one of the most studied anabolic signalling cascades
- +Strong published evidence for satellite cell activation and lean mass increase in animal models
- +TB-500 provides synergistic effect by improving vascular supply and satellite cell homing without direct anabolic stimulation
- +Well-characterised mechanism enables precise experimental design
- −IGF-1 LR3 must be reconstituted in dilute acetic acid, not water — incorrect reconstitution causes tissue damage at injection site
- −Supraphysiological IGF-1 levels carry theoretical oncogenic risk due to broad receptor activity
- −Hypoglycaemia risk at higher doses — blood glucose monitoring recommended in diabetic-prone models
- −IGF-1 LR3 is essentially unavailable from Canadian vendors as of 2026 — contact vendors directly
- −No human clinical data; animal study results may not translate
- −Most expensive category of Canadian research peptides
Effects Timeline
Based on published study timelines. Human extrapolation is approximate — individual results vary significantly.
Satellite cell activation (Pax7+/BrdU+ staining) is detectable within 7–14 days in published animal models. Measurable increases in muscle fibre cross-sectional area typically require 4–6 weeks of treatment in rodent studies.
What People Research This For
Practical Questions
Why must IGF-1 LR3 be reconstituted in acetic acid, not bacteriostatic water?
IGF-1 LR3 is poorly soluble at neutral pH. Dilute acetic acid (0.1%) lowers pH to solubilise the peptide. However, the acidic solution must be diluted with sterile PBS to physiological pH before injection — injecting the acetic acid solution undiluted causes significant tissue irritation and necrosis at the injection site.
Is IGF-1 LR3 the same as synthetic IGF-1?
No. IGF-1 LR3 has a modified arginine substitution at position 3 and an extended N-terminal sequence that dramatically reduces its binding to IGF-binding proteins (IGFBPs). This prevents the rapid clearance that limits native IGF-1's half-life to ~10 minutes, extending IGF-1 LR3's half-life to approximately 20 hours. The result is prolonged receptor activation from a single dose.
Where to Buy IGF-1 LR3 in Canada
IGF-1 LR3 has limited Canadian vendor availability as of March 2026. Most Canadian vendors do not stock this compound routinely.
Contact vendors directly to check current stock, or see our full Canadian vendor comparison for contact details.