What the studies show
No human dosing study exists. The theoretical concerns are hypoglycaemia, because IGF-1 has insulin-like activity, and the long-term effect of sustained growth signalling — neither measured in people for this analogue.
Animal studies, cell studies, or anecdotes only. This is where almost every viral peptide sits. Promising and proven are different words for a reason.
- 1Dominikowski A, et al. The emerging landscape of performance-enhancing peptides modulating the GH-IGF1 axis: bridging the gap between clinical evidence and patient self-administration.Front Endocrinol, 2026Review of the gap between evidence and self-administration in this class.
In context
IGF-1 LR3 is a modified version of insulin-like growth factor 1, engineered so that it evades the binding proteins that normally control IGF-1 and therefore stays active far longer. It was designed as a cell-culture reagent for laboratories, not as a medicine, and no controlled human trial has ever tested it. Natural IGF-1 is available as an approved drug, mecasermin, for a rare severe deficiency — the LR3 analogue is a different molecule with no clinical file at all.
IGF-1 LR3 is not approved; research reagent. Legal status differs by country — see the regulation section or the jurisdiction pages.
Questions
Is IGF-1 LR3 proven to cause safety in humans?
What studies are behind the grade?
Is IGF-1 LR3 approved for this?
Other outcomes for IGF-1 LR3
- DMuscle growth0 controlled
- DAny clinical outcome0 controlled
Written and maintained by LYO Research — how pages are written and checked. Reviewed 3 September 2026. Grades count human evidence only; see how LYO grades. Not medical advice. Correct this page →