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AMIRAVOResearch Library
Immune & Inflammation · Dosing reference

Thymulin dosage

What the human evidence does and does not show, how long studies ran, and the arithmetic for working with vials.

Not approved — research use onlyCPreclinical researchNone established
Full research pageCycle-length evidenceComparePrefer Amiravo on Google
Regulatory status
Not approved — research use only
Human amounts
None established in humans
Route studied
—
Frequency
Not established
Half-life
Not located in the sources reviewed for any species.
Evidence grade
Grade C · Preclinical research
Vial sizes on the market
Not recorded
Other forms seen
—

What Thymulin is

Thymulin is a nonapeptide produced by thymic epithelial cells whose biological activity exists only when the peptide is bound to zinc; it is studied as a biomarker of zinc and thymic status and in animal models of inflammation, with no approved drug use.

Thymulin is the nonapeptide pGlu-Ala-Lys-Ser-Gln-Gly-Gly-Ser-Asn complexed with zinc 10,11. NMR work on the Zn(II)-nonapeptide complex and immunological work with monoclonal antibodies both indicate that the zinc-bound molecule adopts a specific conformation, and that activity is lost without the metal, so zinc is part of the active entity rather than a cofactor added later 2,10. Reported actions Inflammatory… How it works →

Key evidence

  • Dardenne et al., Proc Natl Acad Sci U S A · 1985 · Laboratory (antibodies, thymic epithelial cells)
    Biological activity was strictly dependent on zinc in the molecule, and two monoclonal antibodies recognised exclusively the zinc-coupled form, indicating a zinc-specific conformation. 2
  • Kanemaru et al., Nat Commun · 2026 · Animals (aged mice) with human myeloid-cell analyses
    Thymulin was identified as a circulating factor declining with age that suppresses myeloid pro-inflammatory cytokine production via NF-kappaB inhibition; it enhanced antitumour T-cell immunity and sensitised tumours to anti-PD-L1 treatment in an age-dependent manner. 1
  • DiSilvestro et al., Biol Trace Elem Res · 2021 · Animals (rats)
    Serum thymulin activity was 61% lower on restricted zinc versus adequate zinc, a larger difference than serum zinc (31%), extracellular superoxide dismutase (18%), 5'-nucleotidase (26%) or liver metallothionein (28%). 3
All studies on the research page

What the human evidence shows

No approved or established human dose

Human studies of Thymulin are listed below by design, population and duration. None was designed or powered to establish an amount, and Amiravo does not reproduce their amounts for a compound approved nowhere.

  • Observational follow-up study within a cluster-randomised maternal supplementation trial; thymulin measured as a biomarker of thymic size and function, not administered; Children aged 9 to 13 years in rural Nepal born to trial participants; 290 participants; duration Single follow-up measurement, roughly 9 to 12 years after birth. 5

How long did human studies run?

No human study durations are recorded for Thymulin.

Cycle-length evidence for Thymulin

Supplies and handling

  • Lyophilized vial
    Sealed vial with the freeze-dried cake. Check the label, lot and the certificate of analysis before opening.
  • Sterile diluent
    The diluent named on the product documentation. Bacteriostatic water contains benzyl alcohol; sterile water does not.
  • Graduated syringes
    Sized to the volume being measured. U-100 insulin syringes are graduated in units where 100 units = 1 mL.
  • Alcohol prep pads
    For wiping vial stoppers before each puncture.
  • Nitrile gloves
    Clean gloves for aseptic handling.
  • Sharps container
    Puncture-resistant container for used needles.
Step-by-step reconstitution guideStorage and transport accessories

Storage

General research-context handling only. Lyophilised peptides of this type are generally kept dry, cool and protected from light and moisture; a metal-peptide complex also raises questions of metal loss or exchange in solution and in the presence of chelators, so aqueous preparations are treated as short-lived. Defer to supplier documentation for the specific lot. No temperatures or preparation steps are given here.

  • Lyophilized (unmixed) vials: typically stored cold and dry, away from light, as the documentation directs. Many are stable longer frozen.
  • Reconstituted vials: typically refrigerated (about 2–8 °C), protected from light and not frozen.
  • Bacteriostatic water contains benzyl alcohol, which inhibits bacterial growth in multi-use vials; sterile water has no preservative.

Handling mistakes and troubleshooting

Added the wrong volume of diluent
The concentration changes, not the amount of compound in the vial. Recalculate with the volume actually added and relabel the vial.
Shook the vial and it foamed
Let it settle in the refrigerator. Foam is a sign of agitation; some peptides aggregate when shaken. Note it on the label.
The solution is cloudy or has particles
Do not use it. Cloudiness can indicate incomplete dissolution, contamination or degradation. Record the lot and contact the supplier with the certificate of analysis.
The powder cake looks melted or shrunken before reconstitution
This can indicate the vial was exposed to heat or moisture. Record the lot and condition on arrival.
Liquid sprayed back when the needle was removed
Pressure built up in the vial. Withdraw a small volume of air while adding diluent to keep pressure neutral.

Regulatory status

Status
Not approved for any use. No Drugs@FDA application record was returned on 24 October 2026 13, and "Thymulin acetate" appears in Category 3 of FDA's 503A bulk drug substances list, the category for substances nominated for compounding without adequate support, as updated May 14, 2026 12. Human work located is observational, using circulating thymulin as a biomarker rather than giving it as a treatment 5.
United States (FDA)
Not approved for any use. An openFDA Drugs@FDA query for thymulin returned no application record on 24 October 2026 13. "Thymulin acetate" appears in Category 3 of FDA's 503A bulk drug substances list, substances nominated for use in compounding without adequate support, as updated May 14, 2026 12.
Sport (WADA)
Not named individually in the sources reviewed; S0 covers substances without governmental approval for human therapeutic use, prohibited at all times 14.

Status varies by country and changes over time. How we describe regulatory status.

Thymulin compared with related compounds

CompoundStatusEvidenceHuman amountsHalf-life
ThymulinNot approved — research use onlyCNone establishedNot located in the sources reviewed for
VesugenNot approved — research use onlyCNone established—
LarazotideInvestigationalBTrial doses—
LL-37Not approved — research use onlyBNone established—
KPVNot approved — research use onlyCNone established—
Thymosin Alpha-1Approved outside the USBNone established—

Frequently asked questions

What doses of Thymulin have been studied in humans?
None that establish an amount. Thymulin is not approved anywhere and the human studies that exist are small and were not designed to find a dose. Amiravo does not publish community or vendor figures.
Is there an established Thymulin cycle length?
No. We found no human studies that report treatment duration for Thymulin.
How much bacteriostatic water should be added to a Thymulin vial?
There is no compound-specific volume. The diluent volume only sets the concentration: concentration = mass in the vial ÷ volume added (for example, 10 mg in 2 mL gives 5 mg/mL). The calculator on this page shows the arithmetic for any combination.
How many units is a given amount on an insulin syringe?
On a U-100 syringe, 100 units = 1 mL. Units for an amount = amount ÷ (concentration per unit). The calculator converts any amount you enter at the concentration you choose; a unit is a volume mark, not an amount of compound.
What is the half-life of Thymulin?
Not located in the sources reviewed for any species.
Is Thymulin FDA-approved?
Not approved — research use only. Not approved for any use. No Drugs@FDA application record was returned on 24 October 2026 13, and "Thymulin acetate" appears in Category 3 of FDA's 503A bulk drug substances list, the category for substances nominated for compounding without adequate support, as updated May 14, 2026 12. Human work located is observational, using circulating thymulin as a biomarker rather than giving it as a treatment 5.

References

  1. Thymulin restrains age-associated myeloid inflammation and enhances cancer immunotherapy Nat Commun. 2026
  2. A zinc-dependent epitope on the molecule of thymulin, a thymic hormone Proc Natl Acad Sci U S A. 1985
  3. Comparison of Thymulin Activity with Other Measures of Marginal Zinc Deficiency Biol Trace Elem Res. 2021
  4. Thymulin and zinc (Zn2+)-mediated inhibition of endotoxin-induced production of proinflammatory cytokines and NF-kappaB nuclear translocation and activation in the alveolar epithelium Mol Immunol. 2009
  5. Prenatal and childhood exposures are associated with thymulin concentrations in young adolescent children in rural Nepal J Dev Orig Health Dis. 2020
  6. Physiology and therapeutic potential of the thymic peptide thymulin Curr Pharm Des. 2014
  7. Thymulin treatment attenuates inflammatory pain by modulating spinal cellular and molecular signaling pathways Int Immunopharmacol. 2019
  8. Thymulin, free or bound to PBCA nanoparticles, protects mice against chronic septic inflammation PLoS One. 2018
  9. Nanoparticle-based thymulin gene therapy therapeutically reverses key pathology of experimental allergic asthma Sci Adv. 2020
  10. NMR study of a lymphocyte differentiating thymic factor. An investigation of the Zn(II)-nonapeptide complexes (thymulin) J Biol Chem. 1988
  11. Thymulin (CID 71300623) PubChem. 2026
  12. Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act (updated May 14, 2026): "Thymulin acetate" appears in Category 3, substances nominated without adequate support FDA. 2026
  13. Drugs@FDA application data queried through openFDA for thymulin (no matching application record returned on 24 October 2026) openFDA / Drugs@FDA. 2026
  14. International Standard: Prohibited List 2026 World Anti-Doping Agency. 2026

Last reviewed October 24, 2026 by the Amiravo editorial team. Editorial policy · Report an error