PEG-MGF
Also known as: Pegylated MGF, PEGylated Mechano Growth Factor, Mechano Growth Factor, Pegylated, PEG Mechano Growth Factor
Buy in shop
PEG-MGF
1 verified vendor, side by side on real prices.
Key Facts: PEG-MGF
- Category
- Growth Hormone
- FDA Status
- Not FDA Approved
- Clinical Status
- Not FDA approved for any use. FDA placed "Mechano Growth Factor, Pegylated (PEG-MGF)" in 503A Category 2 (significant safety risks) in 2023, then removed it in April 2026 because the nomination was withdrawn, not because safety was established. As of FDA's May 14, 2026 update it does not appear in any 503A category, and it is not on the list of substances pharmacies may compound from. FDA has indicated it plans to consult its compounding advisory committee before the end of February 2027. No registered clinical trials found. WADA: prohibited at all times under S2.3, which bans mechano growth factors (MGFs) on the 2026 List.
- Banned in Sport (WADA)
- Prohibited at all times under WADA S2 (growth factors), where mechano growth factors (MGFs) are named.
- Administration
- Subcutaneous or intramuscular injection (forum-reported)
- Typical Dose
- 200-400 mcg 2-3x per week (forum-reported)
- Frequency
- 2-3x weekly in forum protocols
- Duration
- Forum protocols describe 8-16 week cycles with about 4 weeks off; no studied duration exists
How does PEG-MGF work?
Pegylation is a real, well-understood drug technique: attaching PEG makes a molecule bigger, slows how fast the kidneys clear it, and shields it from enzymes. It works for approved drugs, and a pegylated version of full IGF-1 (a different molecule) showed a half-life of 140 to 200 hours in a 2017 first-in-human study. The pitch for PEG-MGF is that the same trick lets the short-lived MGF peptide circulate long enough to act on muscle throughout the body. But PEG also changes how a molecule binds and where it goes, so effects reported for unmodified MGF cannot simply be assumed to carry over. The 2026 review made exactly that point. And since the underlying MGF mechanism was not reproduced in a 2014 pharma study, PEG-MGF is a modification of a hypothesis.
What does the research show?
Searching PubMed for PEG-MGF returns essentially one relevant hit: a 2026 narrative review in Frontiers in Endocrinology (Dominikowski and colleagues) on performance peptides that target the GH and IGF-1 axis. It rated PEG-MGF tier D: no peer-reviewed human studies, no reported route of administration in clinical research, half-life not reported, and safety concerns that are theoretical (based on MGF's link to cancer-cell growth in lab studies). The doses that circulate come from bodybuilding forums, which the review summarized only so doctors can recognize what patients are doing, not as guidance. Everything else people cite is MGF research: cell and animal studies suggesting muscle and heart repair effects, plus a careful 2014 study by Fornaro and colleagues that found no effect of MGF on muscle cells, and no effect of native or stabilized MGF on a separate signaling readout in heart cells. If you are looking for evidence that PEG-MGF builds muscle in humans, it does not exist yet.
What doses have been studied?
Typical Dosingⓘ
Community experience
200-400 mcg 2-3x per week (forum-reported)
100-400 mcg per injection (forum-reported)
2-3x weekly in forum protocols
There is no human research dose for PEG-MGF. These numbers exist only because a 2026 clinical review catalogued bodybuilding-forum protocols so doctors could recognize them, and the authors stated they must not be read as validated or safe. Forum protocols often time injections 30-60 minutes after training.
Research Dosingⓘ
Scientific studies
No published research doses exist for PEG-MGF. The figures below are bodybuilding-forum protocols as summarized by a 2026 clinical review, which stressed they are not validated or safe.
Doses from Studies
200-400 mcg 2-3 times per week (forum-reported)
Forum taper: 100 mcg, then 200 mcg, then 300 mcg over about 8 weeks
Duration
Forum protocols describe 8-16 week cycles with about 4 weeks off; no studied duration exists
Administration
Subcutaneous or intramuscular injection (forum-reported)
When and how is PEG-MGF taken?
Best Time to Take
Not established (forums suggest post-workout)
Forum-reported 2-3 times weekly; no studied frequency
Food Recommendation
With or without food
Why This Timing?
Forum protocols time it 30-60 minutes after training on the theory that MGF matters most after muscle loading. No study has tested whether timing matters for the pegylated form.
What are the side effects of PEG-MGF?
Not everyone experiences these effects. Individual responses vary based on dosage, duration, and personal factors.
- ●No human safety data exists
- ●Injection site reactions
- ●Theoretical cancer-growth concern (MGF E-peptide stimulated prostate cancer cells in the lab)
- ●Possible low blood sugar is a theoretical concern for IGF-1 analogues
- ●Unknown effects of the PEG chain with repeated use
- ●Product composition is unverified in unregulated supply
- ●Banned in tested sport (WADA S2)
References
- https://pmc.ncbi.nlm.nih.gov/articles/PMC13322892/
- https://www.frierlevitt.com/articles/fda-peptides-do-not-compound-list-update-2026/
- https://www.fda.gov/media/94155/download
- https://pubmed.ncbi.nlm.nih.gov/24253050/
- https://pubmed.ncbi.nlm.nih.gov/28110155/
- https://pubmed.ncbi.nlm.nih.gov/22328223/
Research This Peptide Further
Buy in shop
PEG-MGF
1 verified vendor, side by side on real prices.
Frequently Asked Questions
What does PEG-MGF do?
PEG-MGF is MGF (the synthetic E-domain peptide from the IGF-1Ec splice variant) with a polyethylene glycol chain attached to make it last longer in the body. That is the theory, anyway. We have to be blunt: there is essentially no published research on PEG-MGF itself. A 2026 clinical review of growth-axis peptides put it in its lowest evidence tier, with no peer-reviewed human studies and no published half-life. Everything said about it online is borrowed from MGF lab work, and MGF's own evidence is shaky.
How does PEG-MGF work?
Pegylation is a real, well-understood drug technique: attaching PEG makes a molecule bigger, slows how fast the kidneys clear it, and shields it from enzymes. It works for approved drugs, and a pegylated version of full IGF-1 (a different molecule) showed a half-life of 140 to 200 hours in a 2017 first-in-human study. The pitch for PEG-MGF is that the same trick lets the short-lived MGF peptide circulate long enough to act on muscle throughout the body. But PEG also changes how a molecule binds and where it goes, so effects reported for unmodified MGF cannot simply be assumed to carry over. The 2026 review made exactly that point. And since the underlying MGF mechanism was not reproduced in a 2014 pharma study, PEG-MGF is a modification of a hypothesis.
Is PEG-MGF FDA approved?
No, PEG-MGF is not currently FDA approved. Current status: Not FDA approved for any use. FDA placed "Mechano Growth Factor, Pegylated (PEG-MGF)" in 503A Category 2 (significant safety risks) in 2023, then removed it in April 2026 because the nomination was withdrawn, not because safety was established. As of FDA's May 14, 2026 update it does not appear in any 503A category, and it is not on the list of substances pharmacies may compound from. FDA has indicated it plans to consult its compounding advisory committee before the end of February 2027. No registered clinical trials found. WADA: prohibited at all times under S2.3, which bans mechano growth factors (MGFs) on the 2026 List.
Is PEG-MGF banned in sport?
Prohibited at all times under WADA S2 (growth factors), where mechano growth factors (MGFs) are named.
What are the side effects of PEG-MGF?
Reported side effects include: No human safety data exists, Injection site reactions, Theoretical cancer-growth concern (MGF E-peptide stimulated prostate cancer cells in the lab), Possible low blood sugar is a theoretical concern for IGF-1 analogues, Unknown effects of the PEG chain with repeated use. Individual responses vary based on dosage, duration, and personal health factors.
What is the typical dose of PEG-MGF?
Community-reported common dose: 200-400 mcg 2-3x per week (forum-reported) (2-3x weekly in forum protocols). Range: 100-400 mcg per injection (forum-reported). Administration: Subcutaneous or intramuscular injection (forum-reported). Community-reported doses. Not medical advice. Consult healthcare provider.
Related Peptides
Peptides commonly compared with PEG-MGF or used in similar applications.
Ipamorelin
Clinical TrialsIpamorelin is a synthetic pentapeptide growth hormone secretagogue developed by Novo Nordisk and derived from GHRP-1. It is researched mainly for stimulating the body's own growth hormone (GH) release, and was studied in humans primarily for postoperative ileus and gut motility rather than anti-aging. It is not an approved drug anywhere: it reached Phase II trials, was discontinued for insufficient efficacy, and is now sold only as a research chemical.
Growth HormoneMK-677
Clinical TrialsMK-677 (ibutamoren) is not actually a peptide, it is a small, orally active non-peptide molecule that mimics ghrelin, your hunger and growth-hormone hormone. Taken as a daily pill, it reliably pushes up growth hormone and IGF-1 levels, which is why it is popular for muscle and recovery. It has been through real human trials but was never approved as a drug, and the trials that mattered most for older adults and Alzheimer's came up short.
Growth HormoneHGH (Somatropin)
FDAHuman growth hormone is the real thing rather than a secretagogue: a 191-amino-acid protein identical to what your pituitary makes, produced recombinantly since the 1980s. It is a properly approved medicine for growth hormone deficiency, and it is also the most misused compound in this entire space. Almost everything you read about HGH for anti-aging or physique traces back to a single small 1990 study whose own author later disowned how it was used.
Growth HormoneCJC-1295 (No DAC)
Clinical TrialsCJC-1295 is a synthetic analog of growth hormone-releasing hormone (GHRH), specifically a modified GHRH(1-29). The name covers two different products. CJC-1295 with DAC (Drug Affinity Complex) binds blood albumin, which stretches its half-life to roughly 6 to 8 days and raises GH and IGF-I for days from a single injection; this is the version ConjuChem took to Phase II before abandoning it, and the version the human data are about. CJC-1295 without DAC (Modified GRF 1-29, the form this page is named for) lacks the albumin tether and is much shorter acting, though its human half-life has not been formally published. Neither is an approved drug, both are sold only as research chemicals, and GHRH analogs are banned in sport by WADA.
Growth HormoneTesamorelin
FDATesamorelin is a stabilized analog of growth-hormone-releasing hormone (GHRH 1-44) with a chemical modification that protects it from rapid breakdown. It is FDA-approved (brand name Egrifta) to reduce excess visceral abdominal fat in people with HIV-associated lipodystrophy, which makes it one of the few growth-hormone-axis peptides with a real approval behind it. Its evidence base is solid for that specific population and thinner for the general anti-aging and fat-loss uses it gets promoted for online.
Growth HormoneGHRP-6
Clinical TrialsGHRP-6 is a synthetic six-amino-acid peptide (His-D-Trp-Ala-Trp-D-Phe-Lys-NH2) that tricks the body into releasing its own growth hormone. It was one of the first growth hormone secretagogues ever made, and the hunt to find out why it worked led scientists straight to the discovery of ghrelin. It has no approval as a drug anywhere and is used only as a research compound.
Growth HormoneWant updates on PEG-MGF research?
Get an email when we add new research here, when it is back in stock, or when the price drops.