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Research Use Only: For research use only. Not for human consumption. Content is educational and is not medical advice, diagnosis, or treatment.
Peptides / Peptides / Growth Hormone

IGF-1 LR3

A long-acting recombinant analog of IGF-1 developed for enhanced potency and sustained receptor interaction in preclinical trials.

IGF-1 LR3

Insulin-like Growth Factor 1 Long Arg3 (IGF-1 LR3) is a structurally modified synthetic analog of endogenous IGF-1, engineered with an N-terminal extension and a single amino acid substitution to dramatically reduce binding affinity for regulatory proteins. This modification yields a significantly extended biological half-life, making the peptide a crucial research tool for investigating skeletal muscle hyperplasia, protein synthesis, and metabolic signaling pathways. It is intended strictly for laboratory and preclinical research applications.

Typical dose
50 - 150 mcg per administration in preclinical animal models.
Half-life
Approximately 20 to 30 hours (significantly extended relative to endogenous IGF-1).
Administration
Subcutaneous or localized intramuscular injection in preclinical models.
Research status
Preclinical / research use only.
Calculate a dose

What Is IGF-1 LR3?

IGF-1 LR3 (Long R3 Insulin Like Growth Factor 1) is a modified analog of IGF-1 engineered to extend half life and reduce binding to IGF binding proteins (IGFBPs). This design is discussed as increasing bioavailability and prolonging IGF-1 receptor signaling compared with native IGF-1, which is why it is often studied in anabolic, recovery, and tissue repair research contexts.

Mechanisms of Action

• Bind IGF-1 receptors, driving anabolic and repair related signaling across muscle and connective tissue models
• Reduce IGFBP binding, increasing free fraction availability and extending duration of effect
• Increase protein synthesis signaling and support muscle hypertrophy endpoints
• Extend the anabolic window by maintaining IGF-1 receptor activation over a longer exposure period

Benefits

• Lean mass and muscle growth related endpoints through sustained anabolic signaling
• Faster recovery signals and improved tissue repair related outcomes in some models
• Body composition improvements through increased lipolysis signals while preserving lean tissue
• Connective tissue and joint support endpoints relevant to injury recovery paradigms

Dosing

Strength

Dose

Low

20 mcg per day

Medium

40 to 60 mcg per day

High

80 to 100 mcg per day

Utilized in 4 to 6 week cycles followed by a break period to reduce desensitization related concerns.

Acetic Acid 0.6% Solution is recommended for reconstitution

Safety Profile

IGF-1 LR3 is a high potency compound that warrants conservative handling and close monitoring.

Potential side effects include:

• Hypoglycemia risk signals due to insulin like activity
• Water retention or mild swelling at higher exposures
• Joint pain or discomfort signals in some contexts
• Organ growth related concerns with prolonged systemic IGF-1 activity
• Potential receptor desensitization signaling with extended use, which is why cycling is commonly emphasized

Stacking

Muscle Growth Stack

  • IGF-1 LR3

  • HGH

  • or CJC-1295 (No DAC)/Ipamorelin

  • or Tesamorelin/Ipamorelin

  • or MK-677

Recovery & Injury Healing Stack

  • IGF-1 LR3

  • BPC-157 + TB-500

  • HGH or CJC-1295 (No DAC)/Ipamorelin or Tesamorelin/Ipamorelin

  • Glutathione

Disclaimer: The information provided is intended solely for educational purposes and should not be considered a replacement for professional medical advice. All compounds referenced are not for human consumption.

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