Compound guide · Tier C
Thymalin
A calf thymus extract from the same Russian institute as epitalon, sold as an immune peptide, and frequently confused with thymosin alpha-1, which it is not.
The short answer
Thymalin is regularly sold and discussed as though it were interchangeable with thymosin alpha-1. It is not. Thymosin alpha-1 is a defined 28 amino acid synthetic peptide, approved as Zadaxin in around thirty countries, with an internationally readable evidence base. Thymalin is a peptide fraction extracted from calf thymus, a mixture, registered in Russia, supported by a literature from a single institute that has never been independently reproduced. If you want the thymic peptide with real international regulatory standing, that is thymosin alpha-1 and it is a different product at a different price. Buying thymalin instead is not a cheaper version of the same thing.
At a glance
| Class | Peptide fraction extracted from calf thymus, a mixture rather than a single peptide |
| Developer | Vladimir Khavinson and colleagues, St Petersburg Institute of Bioregulation and Gerontology |
| Sold as | Thymalin, registered in Russia |
| Regulatory status | Registered in Russia and not approved by the FDA, the EMA, the MHRA or the TGA. The clinical literature comes overwhelmingly from the same St Petersburg research network that produced epitalon, and it has not been independently replicated. |
| Compounding status | There is no approved thymalin product in any Western market. Like cerebrolysin, it is an animal tissue derived preparation rather than a synthetic peptide, so compounding an equivalent is not a meaningful concept. |
| Anti-doping | Not specifically named on the prohibited list. |
| Our evidence tier | Tier C. Weak human data |
What it is
Thymalin is a polypeptide fraction obtained by extraction from the thymus of calves, standardised by the manufacturer rather than defined by a single sequence. It sits within the bioregulator framework developed by the Khavinson group, which holds that short peptide fractions from a given tissue regulate the function of that same tissue.
Who it is for, and who actually takes it
In Russia it has been used in immunodeficiency and as an adjunct in various conditions. There is no approved population outside that jurisdiction.
It is bought by the longevity community for immune support and for age related immune decline, generally alongside epitalon, and often in the belief that it is a form of thymosin alpha-1.
What the research shows
The outcome claims come from a single unreplicated research network. Charting them beside independently verifiable trial data would imply a standing the evidence has not earned.
Dosing
We report only what published research used, and for thymalin that means courses of intramuscular administration described in Russian clinical studies from the originating network. Those parameters come from an unreplicated literature and are recorded as context rather than instruction. We publish no schedule and no reconstitution guidance.
What happens when you come off it
No adequate discontinuation data exists outside that literature, and no controlled Western trial has described what happens when administration stops.
What it is being studied for
| Area | Stage of evidence |
|---|---|
| Immunodeficiency and immune restoration | Russian clinical literature, single network, not replicated |
| Age related immune decline | Same literature, framed within the bioregulator model |
| Long term mortality in elderly cohorts | Reported by the originating group alongside epitalon, not replicated |
| Any outcome confirmed independently | None that we can identify |
The evidence structure here is identical to epitalon, from the same institute, with the same absence of outside replication. Judge them together, because they come from the same place.
Common myths
Thymalin is thymosin alpha-1.
It is not. Thymosin alpha-1 is a defined synthetic 28 amino acid peptide approved as Zadaxin in around thirty countries. Thymalin is an extracted mixture from calf thymus registered in Russia. Conflating them borrows the regulatory standing of one for the other.
It restores your thymus.
Thymic involution with age is real. The claim that administering a thymic extract reverses it has not been demonstrated by any independent group, and the bioregulator model it rests on is not an established framework outside the institute that proposed it.
It is well studied, there are decades of Russian research.
There is decades of research from essentially one network. Duration of publication is not independence of publication, and the whole point of replication is that it comes from somewhere else.
A purity certificate confirms it.
Thymalin is an extracted fraction rather than a single molecule, so a purity percentage does not characterise it in the way it would characterise a synthetic peptide. As with cerebrolysin, ask what was actually measured.
Verifying a purchase
Treat this like cerebrolysin rather than like a synthetic peptide. It is an animal tissue derived mixture, so batch consistency, the controls on the biological starting material and endotoxin are the relevant questions, and a single purity percentage answers none of them. Also confirm you are being sold thymalin and not thymosin alpha-1 or the reverse, because the two are priced differently and confused constantly.
The general method is set out in our guide to reading a certificate of analysis, which covers the eleven checks that apply to any compound. The points above are the ones specific to Thymalin.
Caveats and safety
Bovine tissue origin brings immunogenicity and supply chain considerations that synthesis avoids. There is no Western safety database and no independent pharmacovigilance. Deliberately modulating immune function is a poor idea in anyone with an autoimmune condition or on immunosuppressive therapy, and nobody is making that assessment when a vial is ordered online.
Where to get it
Where to get it
CertaPeptides Romania, EU. Volume discounts at 3+, 5+ and 10+ units.
| Vial | Price |
|---|---|
| 10 mg | €41.99 |
Stated purity. ≥98% stated batch specification. As with cerebrolysin, read that figure carefully on an extracted fraction rather than a single synthesised peptide.
Documentation. Selected lots independently tested by Janoshik Analytical (Czech Republic), HPLC plus mass spectrometry, reports searchable on the Janoshik public portal and at certapeptides.com/verify.
Thymalin is sold as laboratory research material. The vendor states it is not for human consumption and that it is not approved by the FDA, the EMA or any other regulator for use in humans or animals. Read the evidence tier at the top of this page before the price.
View Thymalin at CertaPeptidesAffiliate link. We earn a commission if you buy, at no extra cost to you. It does not change a word of the assessment above. Every product we have priced, in one list.
Sources
- Thymalin and thymic peptide literature, PubMed
- Drugs@FDA, for absence of approval
- European Medicines Agency medicine records, for absence of authorisation
- Registered trials, ClinicalTrials.gov
Related compounds
Disclosure. PeptoPurity is an affiliate of CertaPeptides and earns a commission on qualifying purchases made through the vendor link on this page, at no additional cost to you. That relationship does not set the evidence tier, alter the verdict, or change a word of the assessment. Our Tier C and Tier D pages carry the same links as our Tier A pages, with the same conclusions we would publish if we earned nothing. Where the registered, prescribed route is the better option, we say so on the page that would otherwise pay us.
Scope. This is an evidence review, not medical advice. Where an approved label schedule is reproduced it is a record of what a regulator has published about a licensed medicine, not a recommendation and not a schedule for anyone to follow unsupervised. For unapproved compounds we report only the doses used in published studies, attributed to those studies, and we publish no protocols and no reconstitution guidance for any compound. Regulatory status differs between countries and changes over time. Material sold for laboratory research is not approved for human use. Decisions about treatment belong with a qualified prescriber.