Thymosin Alpha-1
Also called Thymalfasin, Zadaxin, Tα1
What to know about Thymosin Alpha-1
Thymosin alpha 1 is a 28-amino-acid immune-modulating peptide marketed in some countries and studied across infection, immune, and oncology settings.
- How it may work
- Laboratory and clinical research suggests effects on innate immune signalling, dendritic cells, T-cell maturation, and inflammatory balance. Effects vary by disease context.
- What research found
- The 1,106-person TESTS phase 3 trial found no reduction in 28-day all-cause mortality versus placebo in adults with sepsis, superseding optimism from smaller studies.
- What is not settled
- The large phase 3 trial found no statistically significant difference in prespecified safety outcomes, but that result is specific to its seven-day regimen and setting.
- Research and product status
- Thymosin alpha 1 is available as a medicine in some countries but has no licensed U.S. product. Country-specific status should not be generalized.
Research reference
- Research amount range
- 1.6–1.6 mg per administration — not a starting amount
- Reference frequency
- 2x per week — catalogue input, not a personal schedule
- Evidence route
- Subcutaneous in the cited evidence; formulation matters. Sites and rotation
- Model accumulation timescale
- ~10 hours — about five half-lives with regular repeated exposure; not time to a result
- Storage
- Storage and in-use limits depend on the exact formulation and packaging. A compound name alone cannot establish temperature, diluent, or shelf life. Details
A research and community reference, not medical advice. Figures are descriptive, vary between sources, and are not a recommendation for use.
When results may show
- When change was measured
- A large recent sepsis study used a seven-day course and assessed 28-day mortality; it found no significant difference from placebo. Older small studies in other settings are not a universal timeline.
- When to assess
- Outcome timing depends entirely on the specific research setting. The seven-day course and 28-day endpoint cannot be repurposed as a general immune or wellness checkpoint.
- Conditions and limitations
- No evidence supports transferring a hospital study schedule to general use or adding companion compounds. The underlying condition, route, and monitored setting are essential context.
- When to stop
- No broad self-directed maintenance or quit rule exists. A neutral large study does not justify extending exposure for an undefined immune goal.
Research timing is descriptive, not a promise or personal instruction. A severe or persistent reaction needs prompt clinical review. This is not medical advice.
Key properties
- Formula
- C129H215N33O55
- Mol. weight
- 3,108.3 Da
- CAS
- 62304-98-7
- PubChem CID
- 16130571
External references
Vial arithmetic
Published research contexts for Thymosin Alpha-1 describe 1.6–1.6 mg per administration. Descriptive only, not a recommendation.
Roughly 2 hours in plasma.
An immune-modulating peptide licensed as a medicine in roughly 35 countries but never in the US. Human dosing was subcutaneous, so a schedule table is shown; the amount matches the chronic hepatitis B study and the Zadaxin label.
Research schedule reference
Reported schedule context for Thymosin Alpha-1; not a plan to start or adjust personal use.
These are commonly-discussed research protocols shared for educational reference. Study amounts apply to the source's population, formulation, and oversight; they do not establish personal suitability. This is not medical advice and is not a substitute for guidance from a qualified professional.
| Phase | Amount | Frequency | Route |
|---|---|---|---|
| Reported scheduleThe amount and spacing given to trial participants in the chronic hepatitis B study and carried on the Zadaxin label. | 1.6 mg | Twice weekly | SubQ |
Modelled level — 2x per week
1× is the peak after a single dose.
- Steady-state peak
- 1.00× single dose
- Time to steady state
- 10hours
- Administrations
- 2/ week
Read off the modelled curve, not an even-interval formula
About five half-lives
Where these numbers come from
- Andreone P et al., Hepatology 1996A placebo-controlled study of chronic hepatitis B gave thymosin alpha-1 1.6 mg subcutaneously twice weekly to trial participants over about six months.
- Zadaxin (thymalfasin) product labelLicensed as a medicine in roughly 35 countries; the label lists 1.6 mg subcutaneously twice weekly.