IGF1-LR3 is a modified version of insulin-like growth factor-1. The full name of the peptide is insulin-like growth factor-1 long arginine 3. All IGF-1 derivatives play prominent roles in cell division, cell proliferation, and cell-to-cell communication. Though it has similar effects, IGF-1 LR3 does not adhere to IGF binding proteins as strongly as IGF-1. This results in IGF1-LR3 remaining in the bloodstream 120 times longer than IGF-1. IGF1-LR3 gains its prolonged half-life as a result of its structural changes. The peptide is created by adding 13 amino acids to the N-terminal end of IGF-1 and by converting the glutamic acid at position 3 of IGF-1 to an arginine residue.