Informational only. Not medical advice.INFORMATIONAL PLATFORM ONLY — NOT MEDICAL ADVICE, DIAGNOSIS, OR TREATMENT
Informational only. Not medical advice.INFORMATIONAL PLATFORM ONLY — NOT MEDICAL ADVICE, DIAGNOSIS, OR TREATMENT
Head-to-head comparison of GHK-Cu and PEG-MGF — mechanism, dosing, side effects, legal status, and pricing.
GHK-Cu is the copper(II) complex of the human tripeptide glycyl-L-histidyl-L-lysine, first identified in human plasma by Loren Pickart in 1973. Plasma GHK declines with age. It is best established as a topical cosmetic ingredient for photoaged skin; it is NOT an FDA-approved drug in any jurisdiction.
PEG-MGF is the pegylated form of Mechano Growth Factor (MGF), the distinct 24-amino-acid C-terminal E-peptide encoded by the IGF-1Ec splice variant (IGF-1Eb in rodents) that is transiently upregulated in muscle after mechanical loading or damage. MGF is related to but pharmacologically distinct from mature IGF-1 and IGF-1 LR3. Pegylation extends its half-life from minutes to several hours, and the compound is marketed as a research chemical for muscle repair protocols. It is not FDA-approved for any indication.
GHK-Cu
PEG-MGF
Category
Legal Status
Mechanism
Dose Range
Route
COA-verified vendors · trust score ≥70 required · single-vial price — bulk/bundle deals may be lower
GHK-Cu
PEG-MGF
COA corpus from Disclosed Labs — independently tested batches only.
GHK-Cu
215
COAs
99.6%
Avg purity
17
Labs
PEG-MGF
12
COAs
99.6%
Avg purity
5
Labs
GHK-Cu is among peptides under FDA review for the Category 1 (503A) list; if added, it would require a prescription to be compounded by registered 503A/503B pharmacies — not yet authorized. PEG-MGF remains research-only. In April 2026 the FDA removed 12 peptides from Category 2, which does not place them on the Category 1 list or authorize compounding. The FDA's Pharmacy Compounding Advisory Committee is advisory and meets July 23–24, 2026 to review nominations and make recommendations to the FDA.
GHK was identified in human plasma by Pickart in 1973 and characterized as a copper-binding tripeptide in Nature in 1980 (PMID 7453802). Controlled topical studies in photoaged human skin have shown improvements in skin appearance and density with ~2% formulations. Pickart's 2014 review 'GHK and DNA: resetting the human genome to health' (PMID 25302294) and 2018 Int J Mol Sci review 'Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data' (PMID 29986520) summarize transcriptomic data showing modulation of thousands of genes involved in tissue repair, DNA repair, antioxidant defense, and anti-inflammation. The SubQ protocols circulating in the peptide community (typically 1-2 mg) are not supported by controlled human trials.
Key references
Yang and Goldspink (FEBS Lett 2002, PMID 12095637) established that the MGF E-peptide promotes myoblast proliferation and delays terminal differentiation through a receptor distinct from IGF-1R, separating MGF pharmacology from mature IGF-1. Kandalla et al. (Mech Ageing Dev 2011, PMID 21354439) showed the 24-aa MGF E-peptide activates human muscle progenitor cells and enhances their fusion potential even from older donors. Qin et al. (Mol Cell Biochem 2012, PMID 22875667) confirmed MGF drives satellite-cell proliferation while inhibiting differentiation by down-regulating MyoD and p21. Comprehensive reviews by Matheny, Nindl & Adamo (Endocrinology 2010, PMID 20130113) and Zabłocka, Goldspink et al. (Front Endocrinol 2012, PMID 23125840) summarize the evidence across muscle, cardiac and neural tissue and caution that MGF's receptor, in vivo pharmacokinetics, and safety profile remain incompletely characterized. No randomized controlled human trials of PEG-MGF have been published. MGF and IGF-1 analogs are prohibited at all times under the WADA Code.
GHK-Cu (Cosmetic) and PEG-MGF (Performance) are in different categories and target different biological pathways. This is a common pattern in multi-compound research protocols. Researchers should monitor the biomarkers from both profiles and watch for interactions listed in each compound’s contraindications. Consult a licensed healthcare provider before combining any research compounds.
This platform provides informational tools only, not medical advice. This comparison is for educational purposes only. Consult a licensed provider.
Frequency
Dosing Notes
Half-life
Side Effects
Contraindications
Lab Testing
Key references
Disclosed Labs