HEAD-TO-HEAD

EPITALON VS THYMOSIN α-1

Epitalon and Thymosin alpha-1 are two of the most-asked longevity / immune research peptides, with completely different lineages. Epitalon is a synthetic 4-aa Khavinson tetrapeptide (Ala-Glu-Asp-Gly) developed at the St. Petersburg Institute of Bioregulation and Gerontology for pineal-axis longevity research. Thymosin alpha-1 (Tα1) is a 28-aa thymic peptide approved as Zadaxin in 35+ countries as an immunomodulator.

A · No. 023

EPITALON

Telomerase Activator · Khavinson

B · No. 026

THYMOSIN α-1

TA-1 · Zadaxin · Immune Modulator

SIDE BY SIDE

FIELD

A · EPITALON

B · THYMOSIN α-1

Class

Synthetic Khavinson tetrapeptide (4 aa)

Synthetic 28-residue thymic peptide · immunomodulator

Sequence

Ala-Glu-Asp-Gly (AEDG)

28-aa Ac-Ser-Asp-Ala...Asn (thymalfasin)

Primary mechanism

Telomerase modulation · pineal axis · circadian gene expression (proposed)

TLR9 agonism · dendritic-cell maturation · T-cell + NK-cell activation

Half-life

Very short (minutes) plasma; tissue-localized longer

~2 hours plasma (subcutaneous)

Best evidence

Khavinson 2003 PMID 14523389 · 12-year Russian observational mortality study (preliminary)

Multiple Phase 3 trials supporting Zadaxin approval; Wu 2013 PMID 23327199 sepsis trial

FDA status

Not FDA-approved · research-use only

Not FDA-approved in US · approved as Zadaxin in 35+ countries

WADA status

Not listed (2026)

Research focus

Aging / longevity / pineal

Chronic hepatitis B/C · sepsis · immunocompromised support

WHICH IS BETTER · BY GOAL

▶ Approved-product clinical evidenceB · THYMOSIN α-1

Thymosin alpha-1 has Phase 3 trials supporting Zadaxin approval in 35+ countries. Epitalon evidence is dominated by Khavinson-group Russian-language work without comparable Western RCT replication.

▶ Longevity / pineal researchA · EPITALON

Epitalon is the canonical research peptide in the Khavinson pineal-axis longevity tradition. Thymosin alpha-1 is not specifically a longevity compound.

▶ Immune system researchB · THYMOSIN α-1

Thymosin alpha-1 has documented TLR9 agonism, dendritic-cell maturation, and T-cell + NK-cell activation. Epitalon does not have a characterized immune mechanism.

▶ Telomerase axisA · EPITALON

Khavinson 2003 reported telomerase upregulation in human peripheral blood lymphocytes with epitalon. Thymosin alpha-1 does not engage the telomerase axis.

STACKING NOTE

Epitalon and Thymosin alpha-1 act on different systems (pineal/telomerase vs immune) and are not commonly co-administered in published research. Both are used as standalone reference compounds within their respective categories.

SOURCED FROM GIGACOMPOUNDS

Both compounds are available as research-grade material at GigaCompounds · ≥99% purity · per-batch CoA. For laboratory research use only.

SOURCE AT GIGACOMPOUNDS ▶