IGF-1 LR3
Also Known As: Long-Arg3 IGF-I, Insulin-like Growth Factor 1 LR3, IGF1 LR3, IGF-1 LR3, Long R3 IGF-1, Long R3 insulin-like growth factor, IGF LR3, LR3 IGF-1, Des(1-3)-IGF-1 long analog, IGF1-LR3 recombinant, Anabolic growth factor peptide, Muscle growth factor IGF, Somatomedin C analog, Insulin-like Growth Factor 1 Long Arg3, IGF1-LR3
IGF-1 LR3 is a research-grade Long-acting recombinant IGF-1 analog targeting IGF-1 receptor studied in Muscle Growth & Performance research. It is supplied strictly for in vitro laboratory research use only - not for human or animal consumption, and not FDA-approved.
Evidence Tier: Research Compound - No approved human use; sold for laboratory research only.
A potent long-acting IGF-1 analog used as a lab reagent; hypoglycemia and growth risks; banned in sport.
At A Glance
| Category | Muscle Growth & Performance |
|---|---|
| Compound Class | Long-acting recombinant IGF-1 analog (Arg3 substitution, 13 N-terminal extension) |
| Molecular Target | IGF-1 receptor (IGF1R); PI3K/Akt/mTOR signaling; satellite cell proliferation; reduced IGFBP binding = extended half-life |
| Molecular Weight | 9111 Da |
| Amino Acid Sequence | 83-aa analog (Arg3 + N-terminal extension) |
| CAS Number | 946870-92-4 |
| Half-Life | ~20-30 h |
| WADA Status | prohibited |
| Evidence Tier | Research Compound |
Mechanism Of Action
It binds to receptors that trigger massive cell division and growth in muscle tissue. The LR3 modification prevents it from being deactivated by blood proteins, extending its active life from minutes to over 20 hours.
Studied For
- Muscle growth / hypertrophy
- Anabolic research
- GH axis signaling
- Lean mass increase
- Satellite cell activation
- Muscle protein synthesis
- Anti-catabolic research
- Fat loss via anabolic signaling
- Bone density support
- Tendon collagen synthesis
- Nerve growth and repair
- Cartilage repair
- Glucose uptake / insulin sensitivity
- Cell proliferation research
- GH-independent anabolic pathway
- Recovery and repair acceleration
- Body recomposition research
- muscle hyperplasia
- site enhancement
- anabolic
- muscle growth
- recovery
- anti-aging
Reported Research Findings
Validated as a potent cell-culture reagent. Animal data show tissue and muscle growth. There are no controlled human efficacy data; anabolic claims are anecdotal.
Safety And Handling Notes
Mechanistic risks include hypoglycemia (amplified by the long half-life), organ overgrowth, and the potential to promote existing neoplasia.
Not a human therapeutic; the long half-life and binding-protein evasion amplify hypoglycemia and proliferative risk. WADA-prohibited. Research use only.
Regulatory Status
Not FDA-approved for humans (distinct from approved mecasermin); research/cell-culture reagent; WADA S2.
Full Reference Detail
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This Reference Is Provided For In Vitro Laboratory Research Use Only. Not For Human Consumption. See The Full Research Disclaimer.