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Thymosin Alpha-1

Research Use Only
peptideSubcutaneous injection

A 28-amino-acid immune powerhouse originally from thymus tissue. It strengthens both your fast-response and long-term immune systems: helps immune cells (T-cells) mature, boosts your natural killer cells, and balances your immune response so it's neither too weak nor too aggressive. Tested in over 3,000 patients in clinical trials, approved in 35+ countries, and used for hepatitis B/C, HIV support, cancer treatment support, and serious infections. No serious side effects linked to the peptide.

What to Expect

1

Week 1–2

Enhanced innate immune surveillance. May notice fewer early cold/flu symptoms. Subtle improvement in energy if immune system was compromised.

2

Week 3–6

Measurably improved immune function — fewer infections, faster recovery from illness. Enhanced T-cell counts on bloodwork. Improved vaccine response.

3

Week 8+

Sustained immune optimization. Potential anti-tumor immune surveillance benefits. Improved recovery from chronic infections. Reduced autoimmune flare frequency in some users.

Common Side Effects

Injection site discomfortMild flu-like symptoms initiallyTemporary fatigue
Tolerance: None — immune modulation remains effective with continued use
Cycling: 8-12 weeks on, 4 weeks off. Can be used continuously during immune challenges or illness.

Scientific Overview

Thymosin Alpha-1 is a 28-amino acid peptide originally isolated from thymic tissue (Thymosin Fraction 5). It functions as a biological response modifier, enhancing T-cell maturation, dendritic cell function, and natural killer cell activity. TA1 modulates TLR2, TLR5, and TLR9 signaling in dendritic cells and promotes Th1 over Th2 immune responses. Approved in over 35 countries for hepatitis B/C and as an immune adjuvant, with clinical data spanning over 3,000 patients in controlled trials.

Dosing

1.6-2 mg subq once or twice a week. Standard protocol is 1.6 mg twice weekly for 6-12+ months. You can increase frequency if you're fighting off an acute illness. Consistency matters more than timing.

Practical Guide

Reconstitution

Mix 3mg or 5mg vial with 1mL BAC water. Typical dose is 1.6mg (450mcg/kg).

Storage

Refrigerate after reconstitution. Use within 21-30 days.

Injection Sites

Lower abdomenOuter thighUpper arm

Subcutaneous injection with insulin syringe. Rotate sites to prevent lipodystrophy with extended use.

Timing

Morning injection preferred to align with immune system circadian rhythm. Consistent daily timing.

Food

No food interactions.

Benefit Profile

🛡️ Immune Support
10/10
Longevity
5/10
🧊 Inflammation
5/10
🫁 Gut Health
3/10

Medical Considerations

Medical oversight strongly recommendedNot safe during pregnancy

Contraindications

  • Organ transplant recipients on immunosuppression
  • Active autoimmune disease in flare (may exacerbate)
  • Pregnancy/nursing

Drug Interactions

Immunosuppressants (cyclosporine, tacrolimus — opposes their effect)Interferon therapy (additive immune stimulation)Checkpoint inhibitor immunotherapy (excessive immune activation risk)

Recommended Monitoring

  • CBC with differential
  • T-cell subset panel if immunocompromised
  • Monitor autoimmune markers if history

This information is for educational purposes only. Always consult a qualified healthcare provider before starting any peptide protocol.

Pricing

VendorVariantPrice
Limitless Biotech5mg$52.99
Code: PSTACK10Buy
Skye Peptides5mg$54.99
Swiss Chems
FDA warning letter received late 2024
5mg$54.95
Amino Asylum
Reported federal raid in 2025
5mg$44.99BEST
Peptide Sciences
Announced voluntary shutdown
5mg$65.00

Published Research

20 studies indexed(2008–2026)6 meta-analysises6 clinical trials8 reviews

Thymosin alpha 1 alleviates inflammation and prevents infection in patients with severe acute pancreatitis through immune regulation: a systematic review and meta-analysis.

Tian Y, Yao J, et al.·Front Immunol·2025
Meta-Analysis

The Effect of Ulinastatin on Sepsis Outcomes: An Umbrella Review of Meta-Analysis.

Cao S, Han P·Clin Ther·2025
Meta-Analysis

Thymosin Alpha 1 Plus Routine Treatment for the Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis.

Cao A, Feng F, Zhou X·J Coll Physicians Surg Pak·2024
Meta-Analysis

The efficacy of thymosin alpha-1 therapy in moderate to critical COVID-19 patients: a systematic review, meta-analysis, and meta-regression.

Soeroto AY, Suryadinata H, et al.·Inflammopharmacology·2023
Meta-Analysis

The clinical efficacy and adverse effects of Entecavir plus Thymosin alpha-1 combination therapy versus Entecavir Monotherapy in HBV-related cirrhosis: a systematic review and meta-analysis.

Peng D, Xing HY, et al.·BMC Gastroenterol·2020
Meta-Analysis

Comparison of the efficacy of thymosin alpha-1 and interferon alpha in the treatment of chronic hepatitis B: a meta-analysis.

Yang YF, Zhao W, et al.·Antiviral Res·2008
Meta-Analysis

Neoadjuvant immunochemotherapy plus thymalfasin in locally advanced gastric cancer: a prospective clinical trial.

Xu H, Li F, et al.·BMC Med·2026
Clinical Trial

The efficacy and safety of thymosin α1 for sepsis (TESTS): multicentre, double blinded, randomised, placebo controlled, phase 3 trial.

Wu J, Pei F, et al.·BMJ·2025
Clinical Trial

A Prospective and Randomized Control Study on Effects of Thymalfasin for Injection on Perioperative Immune Function and Long-term Prognosis of Patients with Colorectal Cancer.

Niu W, Li Z, et al.·Biotechnol Genet Eng Rev·2024
Clinical Trial

A pilot trial of Thymalfasin (Ta1) to prevent covid-19 infection and morbidities in renal dialysis patients: Preliminary report.

Tuthill CW, Awad A, et al.·Int Immunopharmacol·2023
Clinical Trial
Showing 10 of 20 studies. Search PubMed for the complete list.