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GHK-Cu vs TB-500 side-by-side

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GHK-CuTB-500

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Property	GHK-Cu	TB-500
Category	Skin & Hair	Healing
Also known as	Copper Peptide, Glycyl-L-histidyl-L-lysine copper	Thymosin Beta-4 fragment (LKKTETQ), Thymosin Beta-4, Fragment
FDA approved	No	No
Clinical status	Used in cosmetic products with limited human topical-skincare evidence; the source also notes injectable compounding restrictions and a pending reclassification process. Pre Preclinical I Phase I II Phase II III Phase III IV Phase IV FDA FDA approved	Preclinical - No human clinical trials. FDA Category 2 (pending reclassification to Category 1 per April 15, 2026 HHS announcement; remains Category 2 under current law until formal FDA rule; PCAC review July 23-24, 2026) Pre Preclinical I Phase I II Phase II III Phase III IV Phase IV FDA FDA approved
What to expect	Skin rejuvenation, wound healing, hair growth, anti-aging	Muscle recovery, wound healing, injury rehabilitation
How it works	GHK-Cu is described as the copper(II) complex of the GHK tripeptide. The source connects its activity to copper binding and possible cellular copper delivery, but also emphasizes effects that go beyond a simple carrier model. Reported laboratory observations include shifts in gene expression, increased fibroblast production of extracellular-matrix components, keratinocyte support, vascular-related activity, and antioxidant or anti-inflammatory signals. The precise mechanism is still not fully defined.	TB-500 is presented as a synthetic peptide based on the thymosin beta-4 active region. The supplied source identifies LKKTETQ, residues 17 to 23, as the short sequence commonly reproduced in TB-500 products and ties that region to G-actin binding. Through this actin-related pathway, thymosin beta-4 research connects cytoskeletal remodeling with cell migration into wound areas. The source also reports anti-inflammatory and pro-angiogenic activity in lab models. The main uncertainty is translational: evidence from full-length thymosin beta-4 does not prove that a 7-amino-acid fragment will reproduce the parent molecule's full biological profile.
Typical dosing	1-2 mg daily injection or 0.05% topical · Once daily · Subcutaneous injection or topical application	2-2.5 mg twice weekly (loading), then 2.5 mg once weekly (maintenance) · 2x weekly for 4-6 weeks, then 1x weekly
Research dosing	1-2 mg for injectable protocols · Varies by application · Subcutaneous injection or topical application	2-2.5 mg twice weekly · 4-6 weeks loading, then maintenance · Subcutaneous or intramuscular injection
Typical duration	Varies by application	4-6 weeks loading, then maintenance
Administration	Subcutaneous injection or topical application	Subcutaneous or intramuscular injection
Timing	Evening for skin or recovery contexts With or without food	Morning or evening With or without food
Evidence level	Clinical Trials	Preclinical
Possible side effects	Generally well tolerated (Reported as a general tolerability statement in the source.) Mild topical irritation, redness, or tingling (Associated with topical use.) Injection-site reactions (Associated with injectable use.) +4 more Possible histamine release (Source advises caution for MCAS or histamine sensitivity.) Copper toxicity risk with excessive use (Risk described for excessive exposure.) Wilson's disease contraindication (Source lists Wilson's disease as contraindicated.) Caution with active cancer (Source flags an angiogenesis-related concern.)	Generally well-tolerated in preclinical studies (Preclinical observation; long-term human safety data are limited.) Injection site reactions Headache +7 more Fatigue Nausea May trigger histamine release (Source advises caution for MCAS or histamine sensitivity.) Theoretical risk of facilitating tumor cell migration (Source notes thymosin beta-4 is upregulated in metastatic cancers.) Contraindicated with active cancer or cancer history (Source-supported contraindication note.) Limited long-term safety data WADA prohibited at all times (Listed in the source as prohibited on the 2025 WADA list.)
Research summary	The source describes a mixed evidence base. Cell and animal work is reported for wound repair, collagen deposition, fibroblast activity, elastin and growth-factor production, keratinocyte protection, and lung-injury models. Human data are described as small topical cosmetic studies, including facial-cream and eye-cream studies with 71 and 41 participants that reported changes in skin density, thickness, and wrinkle appearance. These data are encouraging for topical skin endpoints but do not establish injected or systemic benefits.	The supplied research summary places TB-500 mainly in a preclinical evidence category and says most of the stronger evidence concerns full-length thymosin beta-4 rather than the TB-500 fragment. It reports animal findings in wound, scar, tendon, skin, and cardiac injury models. For human data, the source discusses RegeneRx programs using thymosin beta-4 forms: RGN-259 eye drops in a placebo-controlled Phase 3 neurotrophic keratopathy study, where corneal healing was reported in 6 of 10 treated patients versus 1 of 8 on placebo, and RGN-352 injection, which reached Phase 2 in a cardiac program before a manufacturing hold. These programs are not presented as human efficacy trials of the 7-amino-acid TB-500 fragment. For TB-500 as a fragment, the source states there are no completed, published human efficacy trials for muscle or tendon repair and mentions a recently listed cardiovascular biomarker study as early-stage.
References	PubMed PubMed +1 more PubMed	Source Source +2 more Source Source
Full profile	View Details	View Details

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Educational use only. This information is aggregated from public research and community reports. It is not medical advice, and dosing details are descriptive, not recommendations. Always consult a qualified healthcare professional.

Property

GHK-Cu

TB-500

Category

Skin & Hair

Healing

Also known as

Copper Peptide, Glycyl-L-histidyl-L-lysine copper

Thymosin Beta-4 fragment (LKKTETQ), Thymosin Beta-4, Fragment

FDA approved

Clinical status

Used in cosmetic products with limited human topical-skincare evidence; the source also notes injectable compounding restrictions and a pending reclassification process.

Pre
Preclinical
I
Phase I
II
Phase II
III
Phase III
IV
Phase IV
FDA
FDA approved

Preclinical - No human clinical trials. FDA Category 2 (pending reclassification to Category 1 per April 15, 2026 HHS announcement; remains Category 2 under current law until formal FDA rule; PCAC review July 23-24, 2026)

Pre
Preclinical
I
Phase I
II
Phase II
III
Phase III
IV
Phase IV
FDA
FDA approved

What to expect

Skin rejuvenation, wound healing, hair growth, anti-aging

Muscle recovery, wound healing, injury rehabilitation

How it works

GHK-Cu is described as the copper(II) complex of the GHK tripeptide. The source connects its activity to copper binding and possible cellular copper delivery, but also emphasizes effects that go beyond a simple carrier model. Reported laboratory observations include shifts in gene expression, increased fibroblast production of extracellular-matrix components, keratinocyte support, vascular-related activity, and antioxidant or anti-inflammatory signals. The precise mechanism is still not fully defined.

TB-500 is presented as a synthetic peptide based on the thymosin beta-4 active region. The supplied source identifies LKKTETQ, residues 17 to 23, as the short sequence commonly reproduced in TB-500 products and ties that region to G-actin binding. Through this actin-related pathway, thymosin beta-4 research connects cytoskeletal remodeling with cell migration into wound areas. The source also reports anti-inflammatory and pro-angiogenic activity in lab models. The main uncertainty is translational: evidence from full-length thymosin beta-4 does not prove that a 7-amino-acid fragment will reproduce the parent molecule's full biological profile.

Typical dosing

1-2 mg daily injection or 0.05% topical · Once daily · Subcutaneous injection or topical application

2-2.5 mg twice weekly (loading), then 2.5 mg once weekly (maintenance) · 2x weekly for 4-6 weeks, then 1x weekly

Research dosing

1-2 mg for injectable protocols · Varies by application · Subcutaneous injection or topical application

2-2.5 mg twice weekly · 4-6 weeks loading, then maintenance · Subcutaneous or intramuscular injection

Typical duration

Varies by application

4-6 weeks loading, then maintenance

Administration

Subcutaneous injection or topical application

Subcutaneous or intramuscular injection

Timing

Evening for skin or recovery contexts

With or without food

Morning or evening

With or without food

Evidence level

Clinical Trials

Preclinical

Possible side effects

Generally well tolerated (Reported as a general tolerability statement in the source.)
Mild topical irritation, redness, or tingling (Associated with topical use.)
Injection-site reactions (Associated with injectable use.)

+4 more

Possible histamine release (Source advises caution for MCAS or histamine sensitivity.)
Copper toxicity risk with excessive use (Risk described for excessive exposure.)
Wilson's disease contraindication (Source lists Wilson's disease as contraindicated.)
Caution with active cancer (Source flags an angiogenesis-related concern.)

Generally well-tolerated in preclinical studies (Preclinical observation; long-term human safety data are limited.)
Injection site reactions
Headache

+7 more

Fatigue
Nausea
May trigger histamine release (Source advises caution for MCAS or histamine sensitivity.)
Theoretical risk of facilitating tumor cell migration (Source notes thymosin beta-4 is upregulated in metastatic cancers.)
Contraindicated with active cancer or cancer history (Source-supported contraindication note.)
Limited long-term safety data
WADA prohibited at all times (Listed in the source as prohibited on the 2025 WADA list.)

Research summary

The source describes a mixed evidence base. Cell and animal work is reported for wound repair, collagen deposition, fibroblast activity, elastin and growth-factor production, keratinocyte protection, and lung-injury models. Human data are described as small topical cosmetic studies, including facial-cream and eye-cream studies with 71 and 41 participants that reported changes in skin density, thickness, and wrinkle appearance. These data are encouraging for topical skin endpoints but do not establish injected or systemic benefits.

The supplied research summary places TB-500 mainly in a preclinical evidence category and says most of the stronger evidence concerns full-length thymosin beta-4 rather than the TB-500 fragment. It reports animal findings in wound, scar, tendon, skin, and cardiac injury models. For human data, the source discusses RegeneRx programs using thymosin beta-4 forms: RGN-259 eye drops in a placebo-controlled Phase 3 neurotrophic keratopathy study, where corneal healing was reported in 6 of 10 treated patients versus 1 of 8 on placebo, and RGN-352 injection, which reached Phase 2 in a cardiac program before a manufacturing hold. These programs are not presented as human efficacy trials of the 7-amino-acid TB-500 fragment. For TB-500 as a fragment, the source states there are no completed, published human efficacy trials for muscle or tendon repair and mentions a recently listed cardiovascular biomarker study as early-stage.

References

+1 more

+2 more

Full profile