IGF-1LR3 1MG

IGF-1 LR3 (Long Arg3-IGF-1) is a synthetic analog of insulin-like growth factor 1 (IGF-1), a hormone naturally produced primarily by the liver in response to growth hormone stimulation. The “LR3” modification — a substitution at the Arg3 position plus an extended 13-amino-acid sequence — was originally engineered for laboratory research purposes: it significantly reduces binding to IGF-binding proteins, which extends its half-life and potency compared to native IGF-1.

Research background:

• IGF-1 itself plays a central role in cell growth, muscle protein synthesis, and tissue repair — it’s part of the growth hormone/IGF-1 axis.

• LR3’s modifications make it stay active in the bloodstream much longer than natural IGF-1, which is why it was of interest in lab research on muscle growth and cell signaling pathways.

• It has legitimate use as a laboratory research reagent in cell culture studies, where its extended half-life and reduced binding-protein interference make experimental results more consistent.

• Outside of lab/cell-culture contexts, there’s essentially no human clinical trial data — it has never been developed or tested as a human therapeutic.

Important caveats:

• It’s not FDA-approved for any human use and is not a recognized therapeutic — it’s sold as a research chemical, “not for human consumption.”

• It’s a substance with real physiological potency: because it evades normal binding-protein regulation, it doesn’t have the body’s usual “brakes” on IGF-1 activity, which is a meaningful safety consideration if used off-label in humans (hypoglycemia risk, potential effects on cell/tissue growth regulation).

• It’s known in bodybuilding/performance-enhancement circles for muscle-growth effects, but that use is unsupervised, off-label, and unsupported by human safety data.

• It’s banned by WADA and most professional sports anti-doping bodies.