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IGF-1 LR3 (Long R3 IGF-1) is a modified analog of insulin-like growth factor 1 with an arginine substitution at position 3 and a 13-amino-acid extension. These modifications reduce IGF binding protein affinity, increasing potency and half-life compared to native IGF-1.
Summary: Activates IGF-1 receptors with enhanced potency due to reduced binding protein sequestration, stimulating muscle protein synthesis, cell proliferation, and anti-apoptotic signaling. Mechanisms (reported/proposed across domains): Muscle growth / anabolic • Binds IGF-1 receptor (IGF-1R) with similar affinity to native IGF-1, activating PI3K/Akt and MAPK/ERK signaling cascades that drive...
Investigational - Higher Risk Profile
Dose: 20–100 mcg · Route: Subcutaneous (SC) · Intramuscular (IM) · Frequency: 1× daily · Duration: 4–6 weeks (cycles)