IGF-1 LR3
Also known as: Long R3 IGF-1
A modified IGF-1 that binds IGF binding proteins far more weakly than native IGF-1, leaving it free to act as a potent, long-acting agonist at the IGF-1 receptor.
This page is a structured profile. Narrative evidence, dosing context and FAQs live on the research guide — not duplicated here as a second full article.
- Drug class
- IGF-1 analog / IGF-1 receptor agonist (research reagent)
- Primary targets
- IGF-1R
- Dose reference
- No validated human dose; research reagent only
- Half-life
- ~20-30 hours (reported, non-clinical estimate)
- Developer / origin
- GroPep Ltd (Adelaide, Australia)
- Reference year
- 1992
- Evidence score
- 2/5 - Preclinical / reagent only
Preclinical / reagent only
IGF-1 LR3 is well characterized as a cell-culture supplement and in animal infusion studies, but there is essentially no controlled human therapeutic data.
Mostly animal, ex vivo, cell, or indirect evidence.
Evidence basis
- Reduced IGFBP affinity with retained IGF-1R binding
- Validated potency in serum-free cell culture
- Animal infusion studies showing disproportionate organ growth
- No published controlled human therapeutic trials
Key references
How to read this entry
Dose references and half-life values are pulled from trial protocols, labels, reviews, or published summaries where available. They are context for research and comparison, not a personal dosing recommendation.
Status matters: approved drugs have regulated indications; investigational compounds are still being studied; research-only peptides do not have established human dosing, safety, or efficacy for consumer use.
IGF-1 LR3 guides
Read the matching guide or adjacent research pages for more context.
Peptide calculators
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Compare with related peptides
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