Thymosin Alpha-1 Quick Start
Thymosin Alpha-1 is an N-acetylated 28-amino-acid peptide originally isolated from thymic tissue, where it participates in T-cell maturation. Unlike most compounds in this catalog it is an approved medicine in a number of countries — marketed as thymalfasin for hepatitis B and C and as a vaccine adjuvant — which gives its reference dose an unusually firm basis.
This guide is an educational research reference. It does not diagnose, treat, or prescribe, and is not medical advice. Consult a licensed clinician before considering any compound.
Thymosin Alpha-1 Dosing Protocol
The reference dose comes from the approved product: 1.6 mg subcutaneously, twice weekly. That figure has a clinical basis rather than a community-derived one, which is unusual for this catalog. It is shown as research context, not a personal dosing recommendation.
Injection — Subcutaneous
| Band | Per dose | Frequency |
|---|---|---|
| Reference | 1.6 mg | Twice weekly |
| Lower | 0.8 mg | Twice weekly |
Cycle guidelines
| Approach | Duration | Review point | Best for |
|---|---|---|---|
| Short | 4 weeks | Week 4 | General research planning |
| Extended | 6 months | Monthly | Mirrors approved hepatitis regimens |
Thymosin Alpha-1 Reconstitution Guide
Thymosin Alpha-1 ships as a lyophilized powder. At 2 mL the 1.6 mg reference dose is a comfortable 64-unit draw.
Injection
| BAC | Conc. | 1.6 mg |
|---|---|---|
| 2 mL | 2.5 mg/mL | 0.64 mL · 64 u |
| 1 mL | 5 mg/mL | 0.32 mL · 32 u |
Units are U-100 insulin-syringe units (100 u = 1.0 mL).
Reconstitution steps
- Inspect the vial. Confirm the label, expected milligram amount, and that the powder looks dry and intact.
- Wipe the stoppers. Use an alcohol swab on both the bacteriostatic water and peptide vial stoppers.
- Draw the chosen volume. 2 mL into the vial — this is the number that sets every concentration figure above.
- Inject down the wall. Release the water slowly down the inside wall, not directly onto the powder.
- Swirl, do not shake. Roll gently until dissolved. Shaking foams and can damage the peptide.
- Verify clarity. Solution should be clear and colorless. Discard if cloudy or particulate.
- Label and refrigerate. Note the date and volume added on the vial, then store at 2–8 °C. Do not freeze the reconstituted solution.
See the bacteriostatic water guide for diluent handling, or the reconstitution calculator to work any other volume.
How Thymosin Alpha-1 Works
Thymosin Alpha-1 acts on the maturation and differentiation of T cells, and is reported to signal through Toll-like receptors on dendritic cells — particularly TLR9 and TLR2. The result described in the literature is enhanced antigen presentation and a shift toward Th1 cellular immunity. It is characterised as an immune modulator rather than a blanket stimulant, which is the basis for its use as a vaccine adjuvant.
T-cell maturation
The original described role; promotes differentiation of immature thymocytes.
Toll-like receptor signalling
Reported TLR9 and TLR2 activity on dendritic cells, enhancing antigen presentation.
Th1 polarisation
Shifts the response toward cellular immunity.
Open question
Whether immune modulation translates to benefit outside its approved indications is not established.
Who Should Avoid Thymosin Alpha-1
An approved safety profile in specific indications does not transfer to unsupervised use of research-grade material.
Autoimmune conditions
Enhancing cellular immunity is the mechanism — a plausible concern where immunity is already misdirected.
Immunosuppressive therapy
Direct pharmacological opposition; relevant after transplant in particular.
Pregnancy & lactation
No established human safety data.
Anyone seeking a treatment
Approved indications are specific; this is not a general-purpose immune product.
Thymosin Alpha-1 Side Effects & Safety
Generally well tolerated
The approved-use safety record is favourable, with injection-site reactions the most common complaint.
Injection-site reactions
Redness or discomfort at the site; rotate sites.
Autoimmune theoretical risk
Immune enhancement is the mechanism, so the theoretical concern follows directly from it.
Quality-control risk
A 28-amino-acid peptide is a demanding synthesis — verify identity and purity against a COA.
Thymosin Alpha-1 Evidence Context
Approved indications
Marketed as thymalfasin for chronic hepatitis B and C in a number of countries.
Vaccine adjuvant work
Studied as an adjuvant, particularly in immunocompromised and older populations.
Sepsis and critical care
Investigated in sepsis trials with mixed results.
Open question
Evidence outside the approved indications is considerably thinner than its reputation suggests.
Storage & Handling
| State | Storage | Notes |
|---|---|---|
| Lyophilized (powder) | −20 °C, protected from light | More stable than reconstituted solution. |
| Reconstituted (liquid) | 2–8 °C short-term | −20 °C for longer per the listing. |
| Appearance | Clear, colorless | Discard cloudy or particulate solutions. |
Frequently Asked Questions
What is Thymosin Alpha-1?
A 28-amino-acid acetylated peptide originally isolated from thymic tissue, involved in T-cell maturation. It is approved as thymalfasin in a number of countries for hepatitis B and C.
How is it dosed?
The reference schedule from the approved product is 1.6 mg subcutaneously twice weekly. At 2.5 mg/mL that is 64 units on a U-100 syringe.
How many doses in a 5 mg vial?
About three at the 1.6 mg reference — roughly a week and a half on a twice-weekly schedule.
Is it related to TB-500?
Only by name. TB-500 derives from thymosin beta-4, a structurally and functionally unrelated peptide. See TB-500.
Does it boost the immune system?
The literature describes it as a modulator rather than a stimulant — it shifts the response toward Th1 cellular immunity. Whether that helps outside its approved indications is not established.
Is this page medical advice?
No. It is an educational research reference and does not diagnose, treat, or prescribe. Consult a licensed clinician before considering any compound.
Thymosin Alpha-1 Formats & Sourcing
Thymosin Alpha-1 is supplied as a lyophilized powder in a single 5 mg vial. There is no pre-reconstituted pen or spray format. Batch-specific Certificates of Analysis are issued per lot.
| Format | Supplied as |
|---|---|
| Vial | 5 mg lyophilized powder |
Strengths are listed as sold; confirm against the product page and the batch COA before calculating anything.
Reference material for this protocol, with batch COA:
View Thymosin Alpha-1 on Spyro Peptides →References
- Garaci E, et al. Thymosin alpha 1: from bench to bedside. Ann N Y Acad Sci (2007).
- Romani L, et al. Thymosin alpha1 activates dendritic cells via TLR9. Blood (2006).
- Camerini R, Garaci E. Historical review of thymosin alpha 1 in infectious diseases. Expert Opin Biol Ther (2015).
- Wu J, et al. Thymosin alpha 1 in sepsis: a systematic review and meta-analysis. Crit Care (2013).