IGF-1 LR3
Long-Arg3-IGF-I engineered analog — ≠ DES ≠ MGF ≠ PEG-MGF; animal + detection only.
Editorial review:Evidence snapshot
This drawer marks papers. It is not a plan, a dose, or a source. A paper is a bounded report. It is not a protocol. Grades name the object. They are not a safety rating.
Identity lock — not DES, not MGF, not PEG-MGF. IGF-1 LR3 (Long-Arg3-IGF-I / Long-R3-IGF-I) is an engineered IGF-1 analog: an N-terminal extension plus Arg substitution at position 3 that markedly reduces IGFBP binding and alters potency/clearance vs native IGF-1. It is a recombinant research/animal-growth analog, not native IGF-1 and not mecasermin. PubChem lacks a clean CID lock in this pass → To be confirmed; do not invent CAS. ≠ Des(1-3)IGF-1. ≠ MGF / IGF-1 Ec. ≠ PEG-MGF. Black-market detection papers exist; they are analytics, not efficacy. This drawer marks papers. It is not use advice.
Bottom line
Long-R3-IGF-I has a substantial animal and cell literature (organ growth, protein metabolism, IGFBP interactions) and at least one black-market product detection paper (His-tagged Long-R3-IGF-I). Controlled human clinical efficacy trials for IGF-1 LR3 administration are not established in this Selected sources set. Refuse physique glow.
Papers
Analog design / IGFBP-escape framing
PMID 8919033 — Bryant 1996
Tested: design and characterisation of Long-R3-IGF-I muteins with pepsin-resistance properties (analog engineering object).
Does not show: human clinical use.
PMID 11735239 — Devi 2001
Tested: effect of IGFBP-3 on IGF- and IGF-analogue-induced IGF-IR signalling (includes analog framing relevant to LR3-class IGFBP escape).
Does not show: a human LR3 trial.
Animal physiology (not human grades)
PMID 7561636 — Conlon 1995
Tested: Long-R3-IGF-I infusion stimulating organ growth while reducing plasma IGF-I/II and IGFBP concentrations in guinea pigs.
Does not show: human body-composition efficacy.
PMID 9252489 — Hammon 1997
Tested: modulation of the somatotropic axis in neonatal calves by nutrition, GH, and Long-R3-IGF-I.
Does not show: adult human performance outcomes.
PMID 9488001 — Dunaiski 1997
Tested: Long-[R3]-IGF-I reducing growth, plasma GH, IGFBP-3, and endogenous IGF-I in pigs (feedback/axis effects).
Does not show: a desirable human physique indication; highlights axis complexity.
PMID 10370861 — Hill 1999
Tested: action of long(R3)-IGF-1 on protein metabolism in beef heifers.
Does not show: human protein-metabolism RCTs for LR3.
PMID 11999215 — Garnaut 2002
Tested: IGF-I vs Long-R3-IGF-I effects on intestinal absorption/mucosal growth in animal gut models.
Does not show: human gut-therapy approval for LR3.
PMID 15254966 — Xi 2004
Tested: recombinant porcine IGFBP-3 effects on IGF-I and Long-R3-IGF-I-stimulated L6 myogenic cell proliferation/differentiation.
Does not show: human muscle hypertrophy trials.
Black-market analytics (not efficacy)
PMID 20675162 — Kohler 2010
Tested: detection of His-tagged Long-R³-IGF-I in a black-market product (analytical/antidoping-context identification).
Does not show: clinical efficacy, pharmaceutical-grade identity, or safety of seized material.
PMID 37261455 — Lu 2023
Tested: recombinant expression methods for IGF-1 and LR3 IGF-1 fused with xylanase in Pichia (biotech production science).
Does not show: human therapeutic outcomes.
What is not established
Human clinical efficacy or safety for IGF-1 LR3 administration. Equivalence to Des(1-3)IGF-1, MGF, PEG-MGF, or labeled mecasermin. That animal organ-growth papers grade human physique claims. Product identity/purity for unregulated LR3 preparations. This drawer does not provide use advice, schedules, or sourcing.
Selected sources
8919033 11735239 7561636 9252489 9488001 10370861 11999215 15254966 20675162 37261455
Reported experiences
Reported topics are not established benefits.Risks and unknowns
Compare experiences with care.
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