ImmuneLongevity

Thymosin Alpha-1

Polypeptide · Thymic hormone · 28 amino acids

FDA · APPROVED OUTSIDE US (ZADAXIN)

Half-life

~2 hours

Short

minsdays

Route

SubQ injection

Evidence

Approved therapeutic

Risk

Standard

Overview

Known for

Immune system modulator. Enhances T-cell function, NK cell activity, and dendritic cell maturation. FDA-approved in 35+ countries (as Zadaxin) for hepatitis B/C and as cancer immunotherapy adjunct. Balances immune response rather than just stimulating it.

Mechanism

Thymic peptide — enhances T-cell maturation and function (CD4+, CD8+, NK cells, dendritic cells). Modulates immune response without overstimulating.

Key facts

Format
Lyophilized powder
Mechanism targets
Classification
Authoritative
Supply & nature
Natural / Topping UpNatural
FDA category
Approved outside US (Zadaxin)

Evidence & standing

Evidence base
Approved therapeutic
Risk level
Standard
Best studies
6 references
  • Garaci et al. (2003) Int Immunopharmacol 3:1165-71
  • FDA Approved overseas: Zadaxin (approved in 35+ countries, not USA)
  • Extensive clinical use in hepatitis B/C, immunocompromised patients
  • >11,000 patients in published clinical studies
  • King & Tuthill (2016) Vitam Horm 102:151-78 — Immune modulation review
  • NOT FDA APPROVED in USA — Orphan Drug designation granted

Dosage & protocol

Typical dose
1.6mg
Research range
0.9–1.6 mg
Cycle
2 injections/week for 6 months
Onset
21 days first effects
Full effect
70 days
Half-life
~2h
~2 hours
Protocol

1.6mg SubQ twice weekly (standard clinical dose). Some protocols use daily for acute immune challenges.

Time to effects

EARLY: 2-4 weeks

FULL: 8-12 weeks

Week 1-2: Immune modulation beginning at cellular level. No obvious subjective feelings.

Week 2-4: May notice fewer minor infections, faster recovery from illness. Blood work may show improved immune markers.

Week 4-8: Sustained immune optimisation. Reduced frequency/severity of illness.

Week 8-12: Full immune remodelling.

This is NOT a peptide where you 'feel' obvious effects. Benefits are measured in fewer sick days, faster illness recovery, and improved immune blood markers. Minimum commitment: 8 weeks.

Recommended vial
  • 5mg vials

At 1.6mg 2x/wk, 5mg = ~1.5 weeks ✓. 10mg = ~3 weeks ✓. Both work. 5mg for freshness, 10mg for convenience.

Reference figures only

Dosing reflects published laboratory protocols and is not guidance for use in any living subject.

Safety

Reversibility
Fully Reversible
Side effects

Injection site reaction, mild flu-like symptoms initially (immune activation). Generally very well tolerated even long-term.

Interactions

Immunosuppressive drugs (may partially counteract), vaccines (may enhance response — positive interaction)

Handle with research caution

  • Caution with immunosuppressant medications (may counteract immunosuppression in transplant patients)

Storage & handling

Lyophilised
12–24 months
room temp
Reconstituted
2–4 weeks
2–8°C

Videos & talks

Independent educational content from researchers, clinicians and science communicators — not affiliated with Pepnerd.

Educational resources only. Videos are independent third-party content. Pepnerd is not affiliated with these creators and does not endorse or make claims based on their content. All products are for in-vitro research.