Thymopentin
Thymopentin is a thymopoietin fragment in the Thymic Peptide class. Thymopentin reproduces the active site of thymopoietin, a thymic hormone involved in T-cell differentiation. It has been reported to promote maturation of T-cell precursors and to modulate the balance of T-cell subsets and cytokine production.
For research use only.
Key Facts
- CAS
- 69558-55-0
- Molecular Weight (MW)
- 679.8 g/mol
- Half-life
- —
- FDA status
- Not Approved
- Administration Route
- subcutaneous
- Frequency
- —
- Last updated
- Aug 30, 2026
- Reviewed
- Aug 30, 2026
Research summary
Synthetic pentapeptide corresponding to residues 32 to 36 of thymopoietin, the fragment that carries its immunologically active sequence. Used in some countries as an immunomodulator; not FDA-approved.
Peptide Library's Thymopentin 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
- —
- Frequency
- —
- Cycle
- —
- Administration Route
- subcutaneous
- Reconstitution Guide
- —
Sequence & molecular data
| Amino acid sequence | Arg-Lys-Asp-Val-Tyr |
|---|---|
| Molecular formula | C30H49N9O9 |
| Molecular weight | 679.8 g/mol |
| CAS number | 69558-55-0 |
| PubChem CID | 451417 |
| ChEMBL | CHEMBL156025 |
Identifiers link to the public PubChem, FDA Substance Registration (UNII), ChEMBL and DrugBank records for the same entity.
Science
Mechanism of Action
Thymopentin reproduces the active site of thymopoietin, a thymic hormone involved in T-cell differentiation. It has been reported to promote maturation of T-cell precursors and to modulate the balance of T-cell subsets and cytokine production. Its plasma half-life is measured in minutes, which constrains dosing and complicates interpretation of its clinical effects.
Studies
- Experience with thymopentin in the treatment of periarthritis humeroscapularis, tendinitis, and gonarthrosis by local infiltration
- Thymopentin therapy reduces the clinical severity of atopic dermatitis
- Efficacy and safety of systemic treatments for moderate-to-severe atopic dermatitis: a systematic review
- Thymopentin enhances adenoviral oncolytic therapy by regulating macrophages and CD8(+) T cells
- Thymopentin: safety overview
Regulatory & research status
Thymopentin is not an FDA-approved product. It is sold for laboratory research and has no approved medical use.
| FDA status | Not Approved |
|---|---|
| Research status | Research-only compound; no approval pathway listed |
| Availability | Research-Only |
| WADA (sport) | Unknown / Not Listed |
| Library classification | Research-Only |
Benefits
—
Potential Side Effects
No side effects listed yet for this entry.
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.
Thymopentin: frequently asked questions
What is Thymopentin?
Synthetic pentapeptide corresponding to residues 32 to 36 of thymopoietin, the fragment that carries its immunologically active sequence. Used in some countries as an immunomodulator; not FDA-approved.
How does Thymopentin work?
Thymopentin reproduces the active site of thymopoietin, a thymic hormone involved in T-cell differentiation. It has been reported to promote maturation of T-cell precursors and to modulate the balance of T-cell subsets and cytokine production.
Is Thymopentin FDA approved?
No. Thymopentin 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 amino acid sequence of Thymopentin?
Thymopentin has the sequence Arg-Lys-Asp-Val-Tyr, giving a chain of 5 amino acids. Its molecular formula is C30H49N9O9.
What peptides are similar to Thymopentin?
Compounds most often compared with Thymopentin include Thymosin Alpha-1, Thymalin, Thymogen (Oglufanide) and Thymulin. They are grouped by shared mechanism or research area rather than by equivalence, and their regulatory status and evidence base differ.
References
- Experience with thymopentin in the treatment of periarthritis humeroscapularis, tendinitis, and gonarthrosis by local infiltration — Arzneimittelforschung, 1988External reference
- Thymopentin therapy reduces the clinical severity of atopic dermatitis — J Allergy Clin Immunol, 1990External reference
- Efficacy and safety of systemic treatments for moderate-to-severe atopic dermatitis: a systematic review — J Allergy Clin Immunol, 2014External reference
- Thymopentin enhances adenoviral oncolytic therapy by regulating macrophages and CD8(+) T cells — Commun Med (Lond), 2026External reference
- Thymopentin: safety overview — Surv Immunol Res, 1985External 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 Thymopentin 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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