Thymosin Alpha-1 dose range
The amounts people commonly use, from the low end to the high end, with syringe units, schedule and half-life. The 8 published studies are one click away.
Human trials Immune Also called Thymalfasin
Common use ranges
Mostly from the official drug label or its main trials, plus clinic protocols. The 1.6 mg twice-a-week amount is the Zadaxin label dose, and clinic guides repeat it. The 3.2 mg amount is a higher clinic protocol for short use only.
- Half-life
- under 3 hours
- How it is taken
- subcutaneous injection
- How long people use it
- 6 to 12 months on the label (hepatitis B). Clinic courses are often shorter.
- Mixing used for the units
- 10 mg vial + 2 mL water. 1 unit on a U-100 insulin syringe = 50 mcg.
Pick your vial size and how much water you add. The units below change to match.
10 mg vial + 2 mL water: 1 unit = 50 mcg
| Tier | Each dose | Syringe units10 mg vial + 2 mL water | How often | Schedule | Vial lastsat this tier |
|---|---|---|---|---|---|
| Label dose [1] | 1.6 mg | 32 units 0.32 mL | 2x a week | 1.6 mg twice a week, under the skin | about 3 weeks |
| Daily start (some clinics) [2] | 1.6 mg | 32 units 0.32 mL | once a day | Some acute protocols give 1.6 mg every day for the first 2 weeks, then twice a week | 6 days |
| Higher (short term) [3] | 3.2 mg | 64 units 0.64 mL | 2x a week | 3.2 mg twice a week for an acute problem, then back to 1.6 mg | 10 days |
Good to know
- Zadaxin is approved in many countries outside the US. It is not FDA approved.
- Under 40 kg of body weight, the label uses 40 mcg per kg instead.
Sources for these amounts
- Label dose: RxList, Zadaxin (thymalfasin) label ยท FormBlends, thymosin alpha-1
- Daily start (some clinics): FormBlends, thymosin alpha-1
- Higher (short term): FormBlends, thymosin alpha-1
How long people use it: RxList, Zadaxin (thymalfasin) label
Take the Thymosin Alpha-1 chart with you
Get a one-page printable chart for Thymosin Alpha-1, with the syringe units for each vial and water mix. We can also email you when a new Thymosin Alpha-1 study is published.
This page shows what labels, clinics and users report, and what studies gave. It is not medical advice and not a recommendation for anyone. Many of these compounds are not approved for human use. Check your own medicines and lab work with a licensed clinician before using anything.
See the science: 8 published studies
Amounts given to people in studies
How it was given: Under the skin (SC)
Sepsis trials gave 1.6 mg every 12 hours.
Amounts given to animals in studies
Every study used for this page
Proof grade: Human trials. Tested in randomized human trials. Amounts are quoted as each study reported them. Where the abstract does not state an amount, the row says so.
| Study | Who was studied | Amount given, as reported | Route | How often | How long | What the authors reported |
|---|---|---|---|---|---|---|
| PMID 106072561999 | Human, chronic hepatitis B, phase III (n=97) | 1.6 mg vs placebo | Not in abstract | Twice weekly | 6 months, followed 6 more | Complete response 14% vs 4% (P=0.084), not significant |
| PMID 170759912006 | Human, chronic hepatitis B (n=62) | 1.6 mg | SC | Twice weekly | 6 months | Complete response 31.0% at end of treatment, 48.3% at 6-month follow-up; comparator IFN-alpha |
| PMID 227261052012 | Human, HBeAg-positive hepatitis B (51 enrolled: 26 combination, 25 monotherapy) | 1.6 mg thymosin alpha-1 plus peginterferon 180 mcg weekly | Not in abstract | Twice a week for the first 12 weeks | Thymosin 12 weeks, peginterferon 48 weeks | Combination vs peginterferon alone, efficacy not captured here |
| PMID 201948532010 | Human, metastatic melanoma (n=488) | 1.6 mg, 3.2 mg, 6.4 mg (with DTIC plus IFN-alpha); 3.2 mg with DTIC alone | Not in abstract | Not in abstract | Up to 12 months of response assessment | 3.2 mg arms showed enough responses to reject null (10 and 12 vs 4 control); median OS 9.4 vs 6.6 months |
| PMID 233271992013 | Human, severe sepsis, ETASS (n=361) | 1.6 mg (PMC full text) | SC | Twice per day for 5 days, then once per day for 2 days | 7 days | 28-day mortality 26.0% vs 35.0% (P=0.062) |
| PMID 398144202025 | Human, sepsis, TESTS phase 3 (n=1106) | 1.6 mg, every 12 hours (PMC full text; abstract says SC every 12 h) | SC | Every 12 hours | Up to 7 days | 28-day mortality 23.4% vs 24.1%, no benefit |
| PMID 324422872020 | Human, severe COVID-19, retrospective (n=76) | Not stated in the abstract | Not in abstract | Not in abstract | Not in abstract | Mortality 11.11% vs 30.00% (observational, not randomized) |
| PMID 283943302017 | Mouse, Cftr F508del and C57BL/6 (n per group about 3 in shown blots) | 200 mcg/kg (PMC full text) | IP or intranasal | Daily | 6 days | Restored CFTR expression and activity, reduced inflammation. Mouse weight not stated, assumed ~0.025 kg |
How to read the study numbers
- One study, one group. Each figure is what one team chose for its own participants or animals.
- Route matters. An amount given into a vein (IV) is not the same as the same amount under the skin, in the nose or by mouth.
- Animals are not small people. An animal amount is shown as the study gave it. It is not a human amount.
- Short studies. Many studies ran days or weeks. They do not show what happens over longer use.
Common questions
What amounts of Thymosin Alpha-1 were used in human studies?
In the studies listed here, people were given from 1.6 mg twice weekly up to 6.4 mg per dose (melanoma trial). The amount used most often was 1.6 mg per dose. These are what study teams chose for their participants under supervision.
Where do these Thymosin Alpha-1 numbers come from?
From 8 published studies, each linked to its PubMed or ClinicalTrials.gov record. Every figure was checked against the study abstract or its open full text. Proof grade: Human trials.
How long does Thymosin Alpha-1 stay in the body?
Its half-life is under 3 hours in people. Half-life is how long it takes for half of a dose to leave the blood. The effect can last longer than that.
Is this a recommendation for how much Thymosin Alpha-1 to use?
No. This page shows the amounts reported by drug labels, clinics and users, next to what researchers gave in studies. It is not medical advice and not a recommendation for anyone. Talk to a licensed clinician before using any of it.