
D
Tier
Thymus peptide complex for immune restoration.
Immune Support
Peptide complex, calf thymus extract
WADA Status:
Not listed
Human Trial Scoreboard
Completed human RCTs
None registry-listed
Largest Human Study
n=80, unregistered RCT
Longest exposure
12-year follow-up
Most Recent Trial
Single-blind, single-centre
Description
Thymalin is not a single peptide but a complex extracted from calf thymus tissue, containing a mixture of short peptides. It has been used clinically in Russia for decades and it is central to the Khavinson group's longevity work, including a widely cited long-running study in elderly patients reporting substantially reduced mortality. It also has the strongest human evidence of any compound in this bioregulator family: a randomised placebo-controlled Russian trial in eighty patients with severe COVID-19, published in 2021, reported halved hospital mortality. That trial was single-blind, single-centre and unregistered in any international database. It is the closest thing here to real evidence, and it still falls short of the standard that would change practice elsewhere.
What Are The Claims
Claims made for this compound: Restores immune balance; T-cell support
Evidence
The evidence problem here is structural rather than a matter of one weak study. The human claims for the Khavinson peptide bioregulators rest on a small body of largely non-randomized work published mostly within a single journal family, roughly half of it in Russian and unavailable in English translation. The flagship human mortality finding has never been independently replicated outside Russia. The Alzheimer's Drug Discovery Foundation's independent review notes that essentially every preclinical and clinical result traces back to Khavinson's own group with no independent confirmation. A 2025 in-vitro study from Brunel University London did independently support the telomerase mechanism in human cell lines, which is genuinely notable, but it is a cell-culture study that replicates no clinical claim and it carried a published figure correction.
Evidence Strength
Traditional/anecdotal (Russian human data, unblinded)
Caveats
Not FDA-approved; research compound; approved only in Russia; not licensed as a medicine in the US or EU; evidence limited to small unverifiable studies.
Safety
Alternative Measures
Legal Status
US
Not approved
UK
Not approved
EU
Not approved
AU
Not approved
WADA
Not listed
Not approved in the West. Russian peptide preparation. Grey-market elsewhere.
Citations
Khavinson VK, Morozov VG (2003). Neuro Endocrinology Letters. PMID: 14523363. | Alzheimer's Drug Discovery Foundation, Cognitive Vitality independent review. | Brunel University London (2025). Biogerontology. In-vitro telomere study. PMID: 40908429 (figure correction: PMID: 41240216).