IGF-1 LR3

IGF-1 LR3 is a modified version of insulin-like growth factor-1 with an arginine substitution at position 3 and a 13-amino acid N-terminal extension. These modifications reduce binding to IGFBPs and extend half-life. Used in research settings but not FDA-approved for human use.

PubMed results: 10 · Human studies: 2 · Animal studies: 10

Ranges reflect protocols studied in published research and animal-model extrapolation. Presented for research purposes only, not a recommendation or instruction for human use.

• Subcutaneous — standard range 20-100 mcg, Once daily

20-30 hours (moderate confidence)

• Extended IGF-1 receptor pathway activity research (Strong preclinical): IGF-1 LR3 is a modified insulin-like growth factor-1 analog with reduced IGF-binding-protein affinity and extended half-life, studied for prolonged IGF-1 receptor engagement relative to native IGF-1
• Muscle and tissue growth research models (Moderate clinical): Research literature on IGF-1 pathway analogs has examined effects on protein synthesis, satellite-cell biology, and lean-tissue endpoints in experimental and limited translational settings; IGF-1 LR3 itself remains research-use oriented
• Metabolic and recovery pathway research (Limited): Studies of IGF-1 analogs have explored glucose disposal and tissue-repair signaling pathways, though IGF-1 LR3 lacks FDA approval for human therapeutic use and human outcome data are limited

• Hypoglycemia risk (insulin-like activity) — Moderate, Not established. Because IGF-1 receptor activation overlaps with insulin-pathway effects, research frameworks note hypoglycemia risk as a class concern for IGF-1 analogs, though formal frequency data for LR3 specifically are limited
• Edema or soft-tissue swelling — Mild, Anecdotal. IGF-axis research literature describes fluid retention and soft-tissue effects with related growth-factor agents; LR3-specific controlled rates are not well established
• Injection site reactions — Mild, Anecdotal. Parenteral research peptide administration is associated with mild local injection-site reactions in general IGF-analog research use

• Active or history of malignancy (Theoretical / Preclinical): IGF-1 receptor signaling is pro-mitogenic; research and clinical frameworks treat active cancer as a major theoretical and practical concern for exogenous IGF-1 pathway agonists
• Uncontrolled hypoglycemia risk or concurrent insulin research settings (Theoretical / Preclinical): Insulin-like metabolic activity raises concern for additive hypoglycemia when IGF-1 analogs are studied alongside other agents that lower blood glucose

Lyophilized (powder): Refrigerated (2-8°C), Up to 24 months. Light sensitive: yes, store dark

Reconstituted (solution): Refrigerated (2-8°C), 4-6 weeks. Solvent: Bacteriostatic water