# Thymalin

> Thymus-derived polypeptide complex — the founding tissue bioregulator (Cytomax) studied for immune restoration.

- Also known as: Thymulin (distinct), Thymus polypeptide fraction
- Class: Immune, Bioregulators
- FDA approved: No
- Canonical page: https://www.americanpeptide.com/catalog/thymalin

## Overview

Thymalin is a polypeptide fraction extracted from calf thymus, developed by the St. Petersburg school of bioregulation as one of the original "Cytomax" tissue bioregulators. Russian clinical work studied it for restoring T-cell function in aging and immunodeficiency.

Thymalin is a peptide complex isolated from the thymus, introduced in the 1970s–80s as the prototype of the Cytomax class — animal-tissue peptide extracts intended to act as "bioregulators" of the organ they were drawn from. It is the historical anchor of the short-peptide bioregulator program later associated with Vladimir Khavinson.

Unlike the defined short peptides that followed (Epitalon, Vesugen, Pinealon), Thymalin is a heterogeneous polypeptide fraction rather than a single synthetic sequence. Reported research framed it as restoring age- or stress-depleted thymic function. The evidence base is concentrated in Russian-language clinical literature with limited independent Western replication, and it is not FDA-approved.

## Mechanism

Reported normalization of T-lymphocyte populations and cytokine balance; tissue-specific immune regulation.

## Chemistry

| Property | Value |
| --- | --- |
| CAS number | 86402-19-7 |

## Research areas

Studied in: Immune modulation, Aging biology, Peptide bioregulators.

Guides on this site:

- [Longevity & Aging](https://www.americanpeptide.com/research-areas/longevity-aging): Peptides studied across the aging axis — senescence, NAD+, and resilience.
- [Immune & Inflammation](https://www.americanpeptide.com/research-areas/immune-inflammation): Thymic and host-defense peptides studied for immune modulation.
- [Peptide Bioregulators](https://www.americanpeptide.com/research-areas/bioregulators): Short, tissue-specific peptides proposed to regulate gene expression — the Khavinson series.

## Key research

- Immune restoration — Russian clinical studies reported normalization of T-lymphocyte subsets and immune indices in elderly and immunocompromised cohorts.
- Aging / healthspan — long-term observational work from the originating group reported reduced morbidity and mortality endpoints when combined with the pineal preparation epithalamin; these reports are not independently replicated.
- Class context — Thymalin (a tissue extract) is the conceptual parent of the later synthetic Cytogen short peptides such as Vilon (Lys-Glu), a defined dipeptide studied for the same thymic axis.
- Evidence quality — predominantly single-tradition, older, and often open-label; treat findings as preliminary.

## FAQs

### What is Thymalin?

Thymalin is a polypeptide fraction extracted from thymus tissue, studied in Russia as an immune-restoring "bioregulator" and regarded as the founding compound of the tissue-bioregulator class.

### How is it different from the short peptide bioregulators?

Thymalin is a tissue extract (a mix of polypeptides), whereas later bioregulators like Epitalon, Vesugen, and Pinealon are single, defined synthetic short peptides modeled on these extracts.

### How strong is the evidence?

The clinical literature is concentrated in a single research tradition with limited independent replication, so findings should be treated as preliminary. This page is a research and educational reference.

### Is it approved?

No — it is a research compound and is not FDA-approved.

---

Source: AmericanPeptide.com — https://www.americanpeptide.com/catalog/thymalin
Data license: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Attribution: AmericanPeptide.com.
Research reference only — computational and educational content, not medical advice.