Testagen
Also known as: Testis bioregulator, Lys-Glu-Asp-Gly
Testagen (also called Testis bioregulator or Lys-Glu-Asp-Gly) is a khavinson endocrine bioregulator. Testagen is Lys-Glu-Asp-Gly, a synthetic tetrapeptide in the Khavinson series associated with testicular tissue. The proposed mechanism is the series hypothesis of short peptides binding DNA promoter regions in the nucleus and modulating transcription, with reported effects on Leydig and Sertoli cell protein synthesis and on reproductive parameters in animal models.
For research use only.
Key Facts
- CAS
- 1026993-38-3
- Molecular Weight (MW)
- 447.44 g/mol
- Half-life
- Not established (limited public PK data; primarily research context)
- FDA status
- Not Approved
- Administration Route
- Oral or sublingual (common commercial formats); injectable research use exists by supplier
- Frequency
- Once daily (typical research pattern)
- Last updated
- Aug 30, 2026
- Reviewed
- Aug 30, 2026
- Targets
- Testicular cells (proposed)
Vendor price snapshot
Each vendor counts once, at the median price per mg of its own listings; the typical range is the middle half of vendors. From public vendor listings collected between Dec 2025 and Feb 2026, so confirm the live price on the vendor site. Peptide Library does not sell peptides.
- Vendors listing this peptide
- 4
- Listed offers
- 4
- Median price per mg
- $3.00/mg
- Typical $2.88–$3.50/mg
Research summary
Short peptide sold as a testicular/endocrine bioregulator. Not FDA-approved; not a testosterone secretagogue with modern RCT evidence.
Peptide Library's Testagen profile summarises 5 cited studies listed in the Science section, the compound's regulatory status, and research-protocol parameters reported for it. It is a research reference, not medical advice.
Protocol
- Dosage Range
- 5-20 mg daily (research context; not clinically established)
- Frequency
- Once daily (typical research pattern)
- Cycle
- 10-30 days common in bioregulator style protocols (research context)
- Administration Route
- Oral or sublingual (common commercial formats); injectable research use exists by supplier
- Reconstitution Guide
- If lyophilized: reconstitute with bacteriostatic water per lab SOP (research only)
- Injection Sites
- Abdomen (subQ)
- Concentration Example
- 20 mg vial reconstituted with 2 mL = 10 mg/mL
- Timing Notes
- Often taken in the morning; consistency emphasized in short peptide protocols
- Expected Onset
- Variable; proposed cellular signaling effects over weeks
Not yet checked against primary sources
These figures are compiled from earlier reference material. They have not been verified against FDA labelling, registered trials or published literature, no citation is attached to them, and none of them is a recommended dose. Testagen is queued for dosage evidence review.
Compare reported doses across the whole librarySequence & molecular data
| Amino acid sequence | H Lys Glu Asp Gly OH (KEDG) |
|---|---|
| Molecular formula | C17H29N5O9 |
| Molecular weight | 447.44 g/mol |
| CAS number | 1026993-38-3 |
| Half-life | Not established (limited public PK data; primarily research context) |
| Appearance | White lyophilized powder |
| Formulation | Lyophilized Powder |
Identifiers link to the public PubChem, FDA Substance Registration (UNII), ChEMBL and DrugBank records for the same entity.
Science
Mechanism of Action
Testagen is Lys-Glu-Asp-Gly, a synthetic tetrapeptide in the Khavinson series associated with testicular tissue. The proposed mechanism is the series hypothesis of short peptides binding DNA promoter regions in the nucleus and modulating transcription, with reported effects on Leydig and Sertoli cell protein synthesis and on reproductive parameters in animal models. Supporting evidence is cell-culture and cytogenetic work from a single group in Russian-language publications. It is not a treatment for hypogonadism, has no controlled human efficacy data, and is not a substitute for approved testosterone therapy.
Origin
Synthetic short peptide.
Targets
Studies
- The Inhibitory Effect and Adsorption Properties of Testagen Peptide on Copper Surfaces in Saline Environments: An Experimental and Computational Study
- Effect of peptides Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly on the morphology of the thymus in hypophysectomized young and old birds
- [Effects of Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly peptides on hormonal activity and thyroid morphology in hypophysectomized mature and old birds]
- Effects of peptides Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly on hormonal activity and structure of the thyroid gland in hypophysectomized young chickens and old hens
- [Effects of hypophyseal Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly synthetic peptides on immunity, hemostasis, morphology and functions of the thyroid gland in neonatally hypophysectomized chicken and one-year-old birds]
Regulatory & research status
Testagen is not an FDA-approved product. It is sold for laboratory research and has no approved medical use.
| FDA status | Not Approved |
|---|---|
| Availability | Research-Only |
| WADA (sport) | Unknown / Not Listed |
| Library classification | Research-Only |
Benefits
Testagen side effects
Side Effects
- Not characterized
Stacking
Common stacking partners
Combinations that include Testagen, with the proposed rationale, an evidence grade and what is not established, are catalogued in the peptide stacks directory.
Storage & stability
Lyophilized (freeze-dried) peptide powder is far more stable than the reconstituted solution. Keep sealed vials cold, dry and away from light; long-term storage is typically frozen, with short-term refrigeration for vials in use.
Once reconstituted in bacteriostatic water, keep the solution refrigerated, avoid repeated freeze–thaw cycles and agitation, and label the vial with the reconstitution date and concentration. Discard any solution that turns cloudy or shows particulates.
Degradation rates differ by sequence: peptides containing methionine, cysteine, asparagine or glutamine are more prone to oxidation and deamidation, so shelf life after reconstitution is compound-specific rather than universal.
Read the full guide: how to store peptides before and after reconstitution →
Source: Manning MC, Chou DK, Murphy BM, Payne RW, Katayama DS. Stability of protein pharmaceuticals: an update. Pharm Res. 2010;27(4):544–575. (PMID 20143256). General guidance for research handling; not product-specific instructions.
Testagen: frequently asked questions
What is Testagen?
Short peptide sold as a testicular/endocrine bioregulator. Not FDA-approved; not a testosterone secretagogue with modern RCT evidence.
How does Testagen work?
Testagen is Lys-Glu-Asp-Gly, a synthetic tetrapeptide in the Khavinson series associated with testicular tissue. The proposed mechanism is the series hypothesis of short peptides binding DNA promoter regions in the nucleus and modulating transcription, with reported effects on Leydig and Sertoli cell protein synthesis and on reproductive parameters in animal models.
Is Testagen FDA approved?
No. Testagen is not approved by the FDA for any indication and is categorised as research-only. It has not been reviewed for safety or efficacy as a medicine, and published research should be read as investigation rather than established use.
What is the half-life of Testagen?
Reported half-life for Testagen is Not established (limited public PK data; primarily research context). Half-life describes how long the compound persists in circulation, not how long any effect lasts, and published figures vary with route of administration, formulation and the population studied.
What is the amino acid sequence of Testagen?
Testagen has the sequence H Lys Glu Asp Gly OH (KEDG). Its molecular formula is C17H29N5O9.
What peptides are similar to Testagen?
Compounds most often compared with Testagen include Bonomarlot, Bronchogen, Cardiogen and Cartalax. They are grouped by shared mechanism or research area rather than by equivalence, and their regulatory status and evidence base differ.
References
- The Inhibitory Effect and Adsorption Properties of Testagen Peptide on Copper Surfaces in Saline Environments: An Experimental and Computational Study — Molecules, 2025External reference
- Effect of peptides Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly on the morphology of the thymus in hypophysectomized young and old birds — Bull Exp Biol Med, 2013External reference
- [Effects of Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly peptides on hormonal activity and thyroid morphology in hypophysectomized mature and old birds] — Adv Gerontol, 2011External reference
- Effects of peptides Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly on hormonal activity and structure of the thyroid gland in hypophysectomized young chickens and old hens — Bull Exp Biol Med, 2011External reference
- [Effects of hypophyseal Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly synthetic peptides on immunity, hemostasis, morphology and functions of the thyroid gland in neonatally hypophysectomized chicken and one-year-old birds] — Patol Fiziol Eksp Ter, 2010External reference
Related research, comparisons & guides
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Compiled by Peptide Library Editorial · Reviewed Aug 30, 2026 · Updated Aug 30, 2026 · Version 1
This Testagen profile is compiled from published literature (5 cited studies linked above), public regulatory records and chemical registries. It describes what research reports; it is not medical advice, and nothing here is a dosing recommendation for humans. Peptide Library does not sell peptides. Editorial policy · How profiles are compiled · Report an error
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