Insulin-like Growth Factor 1 (IGF-1) is a 70-amino acid protein structurally similar to insulin. It is primarily produced by the liver in response to growth hormone stimulation and mediates many of GH's growth-promoting effects. Recombinant human IGF-1 (mecasermin, brand name Increlex) is FDA-approved for the treatment of severe primary IGF-1 deficiency (primary IGFD) — a condition where patients have normal or elevated GH but fail to produce adequate IGF-1. IGF-1 plays critical roles in growth, development, and metabolism throughout life. It circulates bound to IGF binding proteins (primarily IGFBP-3 in a ternary complex with acid-labile subunit).
12 vendors tracked by PeptideAtlas list IGF-1, priced from $40.00 to $135. The lowest price per milligram is $27.50/mg at Red Fox Peptides (2 mg).
Category: Growth Factor. Evidence rating: A (strong human clinical data).
Clinical status: FDA-approved (Increlex/mecasermin) for severe primary IGF-1 deficiency.
IGF-1 binds to the IGF-1 receptor (IGF-1R), a receptor tyrosine kinase that activates the PI3K/Akt pathway (promoting cell survival and protein synthesis) and the MAPK/ERK pathway (promoting cell proliferation). In circulation, 95-99% of IGF-1 is bound to IGF binding proteins, primarily IGFBP-3 in…
Safety considerations: Hypoglycemia is the most common and serious adverse effect (FDA black box warning on Increlex) — occurs in up to 50% of patients; Must be administered with a meal to reduce hypoglycemia risk; Injection site reactions common.
Reviewed by the PeptideAtlas Editorial Team.
| Molecular weight | ~7649 g/mol |
|---|---|
| CAS number | 67763-96-6 |
| Half-life | ~10-15 min (free); ~12-15 hours (bound to IGFBP-3/ALS complex) |
| Bioavailability | ~100% (subcutaneous) |
| Production method | recombinant |
| Anti-doping status | Prohibited in sport (WADA) |
| US regulatory status | FDA-approved (Increlex, mecasermin) for severe primary IGF-1 deficiency. WADA-banned. |
| Vendor | Size | Price | Price per mg |
|---|---|---|---|
| Red Fox Peptides | 2 mg | $55.00 | $27.50/mg |
| Archer Peptides | 1MG | $40.00 | $40.00/mg |
| Peptide Labs | 1mg | $49.99 | $49.99/mg |
| Wholesale Peptide | 1mg | $50.99 | $50.99/mg |
| Petratide Science | 1mg | $59.95 | $59.95/mg |
| Elite Edge Biotech | 1mg | $65.00 | $65.00/mg |
| Growth Guys | 1mg | $75.00 | $75.00/mg |
| Great Northern Peptides | 1mg | $75.00 | $75.00/mg |
| Peak Peptides | 1mg | $80.00 | $80.00/mg |
| Protide Health | 1mg | $85.00 | $85.00/mg |
| Arcane Peptides | 1MG | $90.00 | $90.00/mg |
| Lucky Link Peptides | 1MG | $135 | $135.00/mg |
Related peptides: IGF-1 LR3, Follistatin 344, MGF.
Primary IGF-1 deficiency means the body produces normal or elevated growth hormone but cannot produce adequate IGF-1, usually due to GH receptor defects (Laron syndrome), IGF-1 gene deletions, or post-receptor signaling defects. These patients do not respond to GH treatment and require direct IGF-1 replacement.
GH is a 191-amino acid pituitary hormone that signals the liver to produce IGF-1. IGF-1 (70 amino acids) then mediates many of GH's growth and anabolic effects. They are sequential components of the same growth axis. GH has additional direct metabolic effects (lipolysis, diabetogenic) that IGF-1 does not share — in fact, IGF-1 has insulin-like glucose-lowering effects.
Epidemiological studies consistently associate higher circulating IGF-1 levels with modestly increased risk of certain cancers (prostate, breast, colorectal). However, association does not prove causation, and IGF-1 levels within the normal range are not considered a cancer risk factor by clinical guidelines. Mecasermin is contraindicated with active malignancy.
Vendors stocking it: Risynth Bio, Reta-Peptide, Zztai Peptide, Ultima Pharmaceuticals, Wholesale Peptide, Petratide Science, SupraChems, Archer Peptides, Elite Edge Biotech, Burly Labs, Catalyst Peptides, BioInfinity Lab, Protide Health, Global Peptide Sciences, Buy Peptides Australia, bodypharm.me | Worldwide Shipping, utherpeptide, Uther, Disguised Alpha, Growth Guys, Great Northern Peptides, Toronto Peptides, Arcane Peptides, Montreal Peptides, Pure Peptides UK, Precision Peptide Co, Wuhan HongyouJie HYJ, Rarevbiolabs.
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