Long-Arg3-IGF-1, Long R3 IGF-1
Evidence Grade D — Primarily preclinical. 10 published studies, mostly animal models. 0 registered clinical trials.
IGF-1 LR3 is a modified version of insulin-like growth factor 1, specifically engineered to bypass the body's natural regulation system. It was developed as a laboratory research tool and cell culture supplement — not as a therapeutic. By evading the binding proteins that normally control IGF-1 activity, it is significantly more potent and less predictable than natural IGF-1. It has no approval for human use.
10 published studies: 2 human, 8 animal, 4 in-vitro, 0 reviews
IGF-1 LR3 has no marketing authorisation for human use. It was developed as a research reagent and cell culture media supplement. No human clinical trials have been conducted. Animal studies characterised its increased potency relative to native IGF-1.
The compound's design specifically circumvents the body's natural IGF-1 regulation — the binding proteins that normally control IGF-1 activity. This means standard IGF-1 safety data cannot be extrapolated to LR3. Products available through unregulated channels lack pharmaceutical quality assurance. Unregulated IGF-1 receptor activation carries theoretical risks including hypoglycaemia.
Research indicates IGF-1 LR3 activates the IGF-1 receptor with the same potency as native IGF-1, but its modifications prevent it from being captured by the binding proteins that normally regulate IGF-1 activity in the body. This means a much higher proportion remains biologically active. The modifications that make it a useful laboratory tool also make it pharmacologically unpredictable for human use — it bypasses the body's normal IGF-1 regulatory mechanisms.
Research in animal models shows IGF-1 LR3 causes significant organ effects — gut weight increased by up to 45% in one study — and promoted tumour growth in tumour-bearing rats. The PI3K/Akt/mTOR pathway it activates is strongly linked to cancer biology. No human pharmacokinetic data, clinical trials, or long-term safety data exist. The compound was designed as a cell culture reagent, and its pharmacological profile reflects this origin — it bypasses the body's normal IGF-1 regulatory mechanisms in ways that create unpredictable effects. Products from unregulated channels lack pharmaceutical quality assurance.
No trials registered on ClinicalTrials.gov for this compound.
The information on this page is provided for educational and research reference purposes only. This is not medical advice. Always consult a qualified healthcare professional before making any health-related decisions.
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