PEG-MGF

PEG-MGF (PEGylated Mechano Growth Factor) is a modified version of MGF with a polyethylene glycol (PEG) chain attached to increase its biological half-life. While native MGF is rapidly degraded in the bloodstream (half-life of minutes), the PEG modification extends the half-life to several hours, enabling systemic administration and distribution to muscle tissue throughout the body rather than requiring local injection. PEGylation is a well-established pharmaceutical strategy used to extend the half-life of protein therapeutics (e.g., PEGylated interferon, PEGylated growth hormone). In the case of MGF, PEGylation trades local potency for systemic reach — PEG-MGF can be administered subcutaneously and reach multiple muscle groups, whereas native MGF must be injected directly into the target muscle.

PEG-MGF retains the core biological activities of native MGF: satellite cell activation through the C-terminal peptide and protein synthesis stimulation through IGF-1R signaling. The PEG moiety reduces renal clearance and protease degradation, extending circulation time. However, PEGylation may partially attenuate receptor binding affinity, potentially reducing acute potency compared to native MGF while providing extended duration of effect.

Systemic Muscle Growth PEG-MGF enables systemic administration for whole-body muscle anabolic effects, unlike native MGF which requires local injection. Muscle Wasting Conditions Research for systemic treatment of sarcopenia, cachexia, and myopathies where local injection is impractical. Recovery from Exercise Studied for recovery from exercise-induced muscle damage through systemic satellite cell activation.

Same as MGF: satellite cell activation, IGF-1R/PI3K/Akt/mTOR, MAPK/ERK for proliferation. Extended pharmacokinetic profile through reduced renal clearance and protease resistance.

Similar profile to MGF with potential additional PEG-related effects: injection site irritation, potential anti-PEG antibody development with chronic use. Hypoglycemia risk. Limited human safety data.

PEG-MGF lyophilized powder stores at -20°C for 12-18 months. More stable than native MGF due to PEG protection. Reconstitute with bacteriostatic water, store at 2-8°C, use within 21 days. Subcutaneous injection is the preferred route (unlike native MGF which requires intramuscular).

Not FDA-approved. Research compound. WADA-prohibited under S2 as an IGF-1-related growth factor.