Thymosin alpha-1: doses reported in published research

Sources checked 2026-10-07 · 5 cited studies (5 human, 0 animal, 0 cell culture)

Thymosin alpha-1 (thymalfasin) is a 28-amino-acid peptide originally isolated from thymus tissue. It has been tested in many human trials, mostly in hepatitis B, liver failure and sepsis, nearly always at 1.6 mg per administration.

Human data: several randomized trials and one uncontrolled trial (hepatitis B, liver failure, sepsis), listed below.

Studies in people (5)

Human Adults with sepsis in intensive care, multicentre phase 3 randomized double-blind placebo-controlled trial (TESTS)

Dose as reported: 1.6 mg
Route: Subcutaneous
Frequency / duration: Every 12 hours for one week

Source wording: Participants in the intervention group received a subcutaneous injection of 1.6 mg every 12 hours we chose 1.6 mg twice daily for one week

Wu J, Pei F, Zhou L et al.. The efficacy and safety of thymosin α1 for sepsis (TESTS): multicentre, double blinded, randomised, placebo controlled, phase 3 trial. BMJ 2025. PubMed PMID 39814420 ↗ · full text PMC11780596 ↗

Human Adults with HBV-related acute-on-chronic liver failure, randomized controlled trial (56 in the active group)

Dose as reported: 1.6 mg
Route: Subcutaneous
Frequency / duration: Once a day in week 1, then twice a week from week 2 to week 12

Source wording: The experimental group (N = 56) was subcutaneously injected with 1.6 mg of Tα1 once a day for the first week and then twice a week from week 2 to week 12.

Chen JF, Chen SR, Lei ZY et al.. Safety and efficacy of Thymosin α1 in the treatment of hepatitis B virus-related acute-on-chronic liver failure: a randomized controlled trial. Hepatol Int 2022. PubMed PMID 35616850 ↗

Human Adults with chronic hepatitis B, randomized controlled study

Dose as reported: 1.6 mg
Route: Subcutaneous
Frequency / duration: Twice a week for 6 months

Source wording: The patients in group A received subcutaneous injection of 1.6 mg thymosin-alpha1, twice a week (T-alpha1 group) for six months

You J, Zhuang L, Cheng HY et al.. Efficacy of thymosin alpha-1 and interferon alpha in treatment of chronic viral hepatitis B: a randomized controlled study. World J Gastroenterol 2006. PubMed PMID 17075991 ↗

Human Adults with HBeAg-positive chronic hepatitis B, randomized pilot study (34 in the combination group, with lamivudine)

Dose as reported: 1.6 mg
Route: Subcutaneous
Frequency / duration: Twice a week for 24 weeks

Source wording: The combination group (n = 34) received Talpha1 (1.6 mg subcutaneously, twice a week) and lamivudine (100 mg orally, daily) for 24 weeks

Lee HW, Lee JI, Um SH et al.. Combination therapy of thymosin alpha-1 and lamivudine for HBeAg positive chronic hepatitis B: A prospective randomized, comparative pilot study. J Gastroenterol Hepatol 2008. PubMed PMID 18410608 ↗

Human Adults with chronic hepatitis B, uncontrolled open-label trial

Dose as reported: 1.6 mg
Route: Subcutaneous
Frequency / duration: Twice a week for 6 months

Source wording: were treated with thymosin alpha 1.6 mg subcutaneously twice a week for 6 months.

Amarapurkar D, Das HS. Thymosin alpha in the treatment of chronic hepatitis B: an uncontrolled open-label trial. Indian J Gastroenterol 2002. PubMed PMID 11990327 ↗

Half-life

Human About 1.5 hours, as stated in the discussion of the TESTS sepsis trial (which cites earlier work for this figure). Source wording: although the half life of the drug is 1.5 hours.
Wu J, Pei F, Zhou L et al.. The efficacy and safety of thymosin α1 for sepsis (TESTS): multicentre, double blinded, randomised, placebo controlled, phase 3 trial. BMJ 2025. PubMed PMID 39814420 ↗ · full text PMC11780596 ↗

About this page

Every figure above is copied from the cited source; the source wording is shown with each entry. Where a source does not state something, the page says so.
Only abstracts, open-access full texts, registry records and FDA labels were used, so details found only in a paywalled full text may be missing.
This page does not convert doses between species or into other measures, and gives no preparation or handling information.