Thymalin

CNot approved (Russia only)Immune, antimicrobial and repair-signal peptides →thymus extract peptidesKhavinson thymic bioregulatorThymalin bioregulator
In one paragraphThymalin is a mixture of short peptides extracted from calf thymus, developed in Soviet-era St Petersburg and sold as an immune 'bioregulator'. The evidence behind its anti-ageing reputation is a 2003 report of 266 elderly people followed for six to eight years, which claims halved mortality but describes neither randomisation nor blinding. No trial outside that group's institute exists in the indexed literature. It is not approved in any region this site covers.
Overall gradeC Weak
Human trials1 uncontrolled long-term series (n=266); Russian reports
Outcomes graded3
Last reviewed23 September 2026
EvidenceWhat it isHow it worksUnknownsMolecule & PKRegulationQuestionsReferences

What the human research shows

The archetype of the bioregulator problem: a striking claim, a single institute, and a study design that cannot support it. Grade C rather than D because human subjects were treated and followed; the certainty is low.

MetabolicCardioMuscleHealingNeuroImmuneSexualSkinAgeing

Evidence profile0–5

  • Metabolic & weight—0.0
  • Cardiovascular—0.0
  • Muscle & growth—0.0
  • Healing & repair—0.0
  • Neuro & sleep—0.0
  • Immune & inflammation—0.0
  • Sexual & hormonal—0.0
  • Skin & appearance—0.0
  • Ageing & longevity—0.0
No benefit outcome for Thymalin has both human evidence and a measurable effect, so the profile is empty. That is the finding, not a gap in the chart.
OutcomeGradeEffect sizeHuman studiesWhere the evidence comes from
Mortality in the elderlyCWeakModerate1 long-term series (n=266, 6–8 yr)Khavinson and Morozov report 2.0–2.1-fold lower mortality in thymalin-treated participants against a control group, and 4.1-fold with annual thymalin plus epithalamin. The abstract does not describe how participants were allocated or whether anyone was blinded; the same authors developed the products.1
Respiratory infectionsCWeakModerateSame seriesA 2.0–2.4-fold fall in acute respiratory disease is reported in the same paper, with the same design limits.1
Independent replicationCWeakNot measurableNone foundLYO's search found no randomised trial of thymalin by any group outside the St Petersburg Institute of Bioregulation and Gerontology.2
AMultiple good human trials, consistentBSome human trials, mostly consistentCFew or weak human studiesDAnimal or anecdotal onlyeffect size · red = adverse

Literature searched to 23 September 2026. Human studies only; animal and cell work informs the mechanism section and nothing else.

What it is

Thymalin is an acid extract of calf thymus containing a mixture of peptides, standardised by biological activity rather than by a defined sequence. It was registered in the USSR in 1982 as an immunomodulator and remains on the Russian market. Vladimir Khavinson's group later derived a synthetic dipeptide, thymogen (Glu-Trp), from it.

Online it is sold alongside epitalon and pinealon as part of a 'bioregulator' set, on the strength of the Khavinson series.

How it is thought to work

The proposed action is restoration of thymic hormone signalling that declines with age, improving T-cell maturation. Laboratory studies from the same group support immune effects; independent mechanistic work is sparse.

What is still unknown

  • What is in it — as an extract, batch composition varies and the active components are not defined.
  • Whether any effect survives a randomised, blinded trial; none has been done.

The molecule and how long it lasts

Identity

An undefined calf-thymus peptide extract — no molecular identity

Pharmacokinetics
Route
Intramuscular as sold
Half-life
No human pharmacokinetic data (an extract, not a defined molecule)

No pharmacokinetic study in people.

Regulatory status

European Union
Not authorised

No marketing authorisation; supply for human use is unlawful.

United States
Not approved

Not FDA-approved; not on any compounding list.

United Kingdom
Not licensed

Unlicensed medicine.

Australia
Not on the ARTG

Not registered.

Canada
Not authorised

No Drug Identification Number.

Sport (WADA)
Prohibited at all times

Unapproved by any regulator WADA recognises, so S0 (non-approved substances).

Questions people actually ask

Does thymalin extend life?
One uncontrolled Russian series says so. Nothing else does. Without randomisation, healthier people may simply have been the ones treated.
Is thymalin the same as thymosin alpha-1?
No. Thymosin α1 is a defined 28-amino-acid peptide with twenty-plus randomised trials. Thymalin is an undefined extract with none.
Is thymalin legal?
It is registered in Russia. It has no authorisation in the EU, US, UK, Australia or Canada, and is banned in sport.

One page per claimed effect

References

  1. 1
    Khavinson VKh, Morozov VG. Peptides of pineal gland and thymus prolong human life.Neuro Endocrinol Lett, 2003;24:233–240266 elderly participants, 6–8 years. No randomisation or blinding described.
  2. 2

Change log

  • 2026-09-23Initial publication. Grade C on the single uncontrolled series.