Thymosin Alpha-1
Also known as: Thymalfasin, Tα1
Quick summary
A 28-amino-acid peptide first isolated from thymus tissue. Research focus: T-cell function, immune modulation and vaccine-response research. This page leads with SRP's low-and-slow starting dose.
Amino acid sequence (one-letter code): SDAAVDTSSEITTKDLKEKKEVVEEAEN
Overview
A 28-amino-acid peptide first isolated from thymus tissue. It is studied for how it affects T-cell maturation and immune signaling.
Looking for research material? Simple Research Peptides lists Thymosin Alpha-1 (10 mg Vial) for laboratory research use.
Mechanism
A 28-amino-acid thymic peptide that modulates innate and adaptive immune signaling, partly through Toll-like receptors.
Research areas
- T-cell function
- immune modulation
- vaccine-response research
Storage & reconstitution
Typically supplied as a lyophilized powder; keep sealed vials cold (refrigerated short term, frozen for long-term holding) and away from light. Laboratories commonly reconstitute with bacteriostatic or sterile water, swirling gently rather than shaking, and keep the solution refrigerated, using it within a few weeks.
Recommended starting dose (low and slow)
| Starting dose | Gives no separate starting step. Its typical range is 1-1.6 mg per dose (subcutaneous or intramuscular), and its single-dose studies use 1 mg. |
|---|---|
| Frequency | 1-3 times per week by subcutaneous or intramuscular injection; its longer-course protocols use 1 mg two to three times weekly over weeks to months. |
| Reconstitution | Example: 5 mg vial + 2 mL bacteriostatic water = 2.5 mg/mL; 1.6 mg = 64 units on a U-100 syringe. Store reconstituted at 2-8 °C. |
1.6 mg SC, the dose used in clinical trials; abdomen, thigh or upper arm.
Studied higher doses
Studies have used doses up to the amounts below. Higher doses can be dangerous. Whether a person can reach them safely depends on height, weight, activity level, training and pre-existing conditions. We recommend following the lower starting dose above, and contacting SRP with any questions.
| Highest amount reported in studies | 2 mg is the highest single amount reported (in a 0.5 / 1 / 2 mg comparison); its typical ceiling is 1.6 mg. It does not call either a verified maximum. |
|---|---|
| Step-up schedules reported | None described. Reports suggest the immune effect looked similar when 0.5, 1 and 2 mg were compared, so no step-up is described; older adults might need slightly more and children less by body weight (no numbers given). |
Route and timing
Route: Subcutaneous injection after reconstitution is the route most often described in research protocols.
Timing: Pending - to be added by SRP
Cycle length and repeat
Pending - to be added by SRP
Half-life
Approximate, for Bobby's review: About 2 hours.
Side effects
Pending - to be added by SRP
Suggested bloodwork and monitoring
Draft, for Bobby's review: CBC and comprehensive metabolic panel (kidney and liver function, electrolytes) before starting and again after a few weeks, with a white-cell differential.
Cautions
Pending - to be added by SRP
Reconstitution calculator
Math aid only. It converts the numbers you enter; it is not dosing advice. For research use only. Prefilled with this page's vial size, reconstitution and low-and-slow starting dose where known; change any value.
Frequently asked questions
What is Thymosin Alpha-1 studied for?
In research it is studied for T-cell function, immune modulation and vaccine-response research. A 28-amino-acid thymic peptide that modulates innate and adaptive immune signaling, partly through Toll-like receptors.
How is Thymosin Alpha-1 given in research?
Subcutaneous injection after reconstitution is the route most often described in research protocols. See the dosing frequency block on this page for how often.
What amount should a researcher start with?
This page lists SRP's low-and-slow starting dose in the Recommended starting dose section. Higher amounts that appear in studies are listed separately with their safety context. Start with the lower dose and contact SRP with any questions.
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Last updated: October 19, 2026