Age and research-use confirmation
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IGF-1 LR3, Long acting IGF-1 analog
A long acting IGF-1 analog engineered to evade binding proteins, driving IGF-1R signaling and muscle hypertrophy, with the steepest risk profile in this library.
Mechanism of action
A long acting IGF-1 redesigned to dodge the proteins that normally rein it in, maximizing muscle growth signaling, and with it the steepest risk profile in this library.
Also studied
Activates IGF-1R to PI3K/Akt protein synthesis and recruits muscle satellite cells; roughly 3× more potent than native IGF-1.
See related compoundsAn Arg3 substitution plus N terminal extension lets it evade IGF binding proteins, stretching half life to ~20-30 hours.
See related compoundsChronically elevated IGF-1 is epidemiologically linked to colorectal, breast, and prostate cancer, and hypoglycemia can be severe. No human trials of the analog exist.
Applications
Bodybuilding use
No human trials of analog
Severe IGF-1 deficiency
Different molecule; FDA approved
Bars indicate how far the evidence has progressed (in vitro to animal to human), not the size of any effect.
Compound data
Full profile
Marketed in bodybuilding for muscle growth. There are essentially no peer reviewed human trials of IGF-1 LR3 itself; all extrapolation is from native IGF-1 (FDA approved as Increlex only for severe primary IGF-1 deficiency).
The most concerning risk benefit on this list: hypoglycemia (can be severe), chronic insulin resistance, and a strong theoretical oncogenic risk, chronically elevated IGF-1 is epidemiologically linked to colorectal, breast, and prostate cancer. Long term high exposure can cause organ/intestinal growth (acromegaly like features).
Active or history of cancer; predisposition to malignancy; diabetes; pregnancy.
Not FDA approved (the analog); sold as a research chemical, illegal for human use in the US/UK/EU. WADA prohibited (S2).
Subcutaneous/IM.
Source: Fnx Performance Peptide Research Database, a synthesis of the scientific and regulatory literature, not medical advice. Anyone considering these compounds should consult a qualified physician.
For Research Use Only. Not for human or animal consumption. These statements have not been evaluated by the FDA. Products are not intended to diagnose, treat, cure, or prevent any disease.
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