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Select Up To Four Compounds To Review Their Evidence, Targets, And Handling Side By Side.
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| Attribute | ||
|---|---|---|
Research Summary | IGF-1 LR3 is the ultimate muscle-building signal. It forces your body to actually create brand new muscle cells instead of just making existing ones bigger. The "LR3" part makes it last a very long time in your body. | Your body has a natural brake pedal that stops your muscles from getting too big. Follistatin cuts that brake cable. Without the brake, your muscles are free to grow much larger and stronger. |
Studied For | Muscle growth / hypertrophyAnabolic researchGH axis signalingLean mass increaseSatellite cell activationMuscle protein synthesisAnti-catabolic researchFat loss via anabolic signalingBone density supportTendon collagen synthesisNerve growth and repairCartilage repairGlucose uptake / insulin sensitivityCell proliferation researchGH-independent anabolic pathwayRecovery and repair accelerationBody recomposition researchmuscle hyperplasiasite enhancementanabolicmuscle growthrecoveryanti-aging | Muscle hypertrophyMyostatin inhibitionFemale fertilityLean muscle mass increaseAnti-myostatin therapyDuchenne muscular dystrophy modelsMuscle wasting / sarcopenia researchStrength gain researchBody recompositionOvarian follicle developmentReproductive hormone regulationFSH inhibitionActivin neutralizationAnabolic signaling amplificationMuscle fiber growthFat mass reduction via muscle increaseAthletic performance researchmuscle growthhypertrophybodybuildingmuscle wastingsarcopenia |
Research Areas | Performance & MuscleTissue RepairJoint & Bone SupportMetabolic | Performance & MusclehormonalHealing & RecoveryTissue Repair |
Best Stacked With | cjc-1295-no-dacipamorelinfollistatinghrp-2bac-water | igf-1-lr3cjc-1295-no-dacipamorelinbac-water |
Overview | ||
Category | Muscle Growth & Performance | Muscle Growth & Performance |
Compound Class | Long-acting recombinant IGF-1 analog (Arg3 substitution, 13 N-terminal extension) | Endogenous glycoprotein / activin-binding protein (recombinant) |
Molecular Target | IGF-1 receptor (IGF1R); PI3K/Akt/mTOR signaling; satellite cell proliferation; reduced IGFBP binding = extended half-life | Myostatin (GDF-8) and activin A neutralization; prevents TGF-beta superfamily inhibition of muscle growth |
Aliases / AKA | Long-Arg3 IGF-IInsulin-like Growth Factor 1 LR3IGF1 LR3IGF-1 LR3Long R3 IGF-1Long R3 insulin-like growth factor | FSTFollistatin 344FS-344Follistatin-344FST344Activin-binding protein |
Parent Compound | Insulin-like growth factor 1 | Human FST gene |
Molecular Weight | 9111 Da | 38000 Da |
Amino Acid Sequence | 83-aa analog (Arg3 + N-terminal extension) | 344-residue glycoprotein |
CAS Number | 946870-92-4 | not standardized |
Year Discovered | Not Listed | Not Listed |
Pro-Angiogenic | No | No |
GLP-1 Class | No | No |
Purity | Not Listed | Not Listed |
Identity | ||
Evidence Tier | ||
Risk Level | ||
PubMed Citations | 57 Moderate | 16,795 Extensive |
Clinical Trials | Not Listed | 3131 Active |
Regulatory Status | Not FDA-approved for humans (distinct from approved mecasermin); research/cell-culture reagent; WADA S2. | Not FDA-approved; experimental. WADA-prohibited (myostatin / activin-pathway agent). |
Evidence & Regulatory | ||
Half-Life | ~20-30 h | ~2 hours |
Typical Frequency | Not Listed | Not Listed |
Administration Route | Injection Only | Injection Only |
Mechanism / PK | Not Listed | Not Listed |
Reported Findings | Validated as a potent cell-culture reagent. Animal data show tissue and muscle growth. There are no controlled human efficacy data; anabolic claims are anecdotal. | Animal gene-therapy studies show large, durable muscle gains. Human data are minimal and limited to localized gene therapy. Injected recombinant peptide is rapidly cleared, a key limitation. |
Side Effects Noted | Mechanistic risks include hypoglycemia (amplified by the long half-life), organ overgrowth, and the potential to promote existing neoplasia. | Sparse human data; theoretical reproductive, cardiac, and tumor-microenvironment effects from broad systemic myostatin and activin blockade. |
Warnings | Not a human therapeutic; the long half-life and binding-protein evasion amplify hypoglycemia and proliferative risk. WADA-prohibited. Research use only. | No approved human use; recombinant peptide pharmacokinetics are poor. WADA-prohibited (myostatin inhibitor). Research use only. |
Pharmacology | ||
Form | lyophilized | lyophilized |
Diluent | dilute acetic acid or sterile/bacteriostatic water per supplier | sterile or bacteriostatic water; gentle, avoid foaming |
Storage Temp | -20C, dark | -20C, dark |
Light Sensitive | Yes | Yes |
Freeze / Thaw | avoid | avoid |
Handling Notes | Aliquot and freeze for longer storage. | Large glycoprotein; rapidly cleared when injected. |
Reconstituted Shelf Life | 14 Days Refrigerated | 14 Days Refrigerated |
Handling & Storage | ||
Pep Nation Lab's comparison tool puts research-grade peptides and compounds head to head - mechanism of action, molecular target, evidence tier, molecular weight, sequence, half-life, and documented research focus - so qualified researchers can evaluate the differences that matter. Every data point is drawn from a referenced monograph. For in vitro laboratory research use only.
The two most-studied research peptides for tissue repair and recovery.
Single GLP-1 versus dual GLP-1/GIP incretin agonists in metabolic research.
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A GLP-1 agonist versus a triple-agonist incretin in metabolic research.
A GHRH analog versus a selective ghrelin-receptor secretagogue.
A ghrelin-receptor secretagogue versus a GHRH analog for growth-hormone research.
Two GHRH analogs studied on the growth-hormone axis.
The two first-generation growth-hormone releasing peptides.
An amylin analog versus a GLP-1 agonist in metabolic research.
A mitochondrial-derived peptide versus an HGH fragment in metabolic research.
Melanocortin versus kisspeptin pathways in reproductive research.
A telomerase-pathway peptide versus NAD+ metabolism in longevity research.
A potent versus a highly selective ghrelin-receptor secretagogue.
Two GHRH analogs with contrasting half-life profiles.
A direct IGF-1 analog versus a growth-hormone secretagogue.
The DAC versus non-DAC forms of the CJC-1295 GHRH analog.
Two Russian-developed nootropic and anxiolytic research peptides.
Two mitochondrial-targeted peptides in cellular-energy research.
Two immune-modulating research peptides with distinct mechanisms.
Two HGH-fragment analogs studied for fat-metabolism research.
Next-generation multi-receptor incretin agonists in metabolic research.
Two leading tissue-repair peptides with distinct healing mechanisms.
A systemic repair peptide versus a copper peptide for tissue and skin research.
A GHRH analog versus a selective ghrelin-receptor secretagogue on the GH axis.
A dual incretin agonist versus an amylin analog in metabolic research.
A triple incretin agonist versus an amylin analog in weight research.
Two metabolic research compounds targeting mitochondrial and NNMT pathways.
NAD+ metabolism versus a mitochondrial-derived peptide in longevity research.
Two copper research peptides studied for skin and hair.
A long-acting versus a short-acting GHRH analog.
A selective versus a first-generation ghrelin-receptor secretagogue.
A GLP-1 agonist versus a GLP-1/amylin combination in metabolic research.
Two peptides studied for gut and mucosal repair.
Melanocortin versus oxytocin pathways in intimacy and libido research.
Two thymic immune-modulating research peptides.
An anxiolytic nootropic versus a sleep-associated research peptide.
Direct IGF-1 signaling versus myostatin inhibition in muscle research.
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Browse the full research catalog or the A To Z index to compare any compound.
Any research-grade compound in the library can be placed side by side - up to four at a time. The tool compares mechanism of action, molecular target, evidence tier, molecular weight, amino acid sequence, reported half-life, and what each compound has been studied for, all drawn from referenced monographs.
The evidence tier reflects how extensively a compound has been studied in the referenced literature, from early preclinical signals through to compounds with human clinical data. It is a research-quality signal only, never a safety or efficacy endorsement.
Each comparison page is generated from the same referenced compound database - a genuine side-by-side of mechanism, identity, pharmacokinetics, and evidence, plus data-derived key differences. They are curated, not auto-generated thin pages.
No. Every comparison is for in vitro laboratory research use only. Nothing here is medical advice, a treatment recommendation, or dosing guidance, and no product is for human or animal consumption.
