Compare Peptides
Select any two compounds for a side-by-side comparison of mechanism, uses, risks, and FDA regulatory status.
Popular comparisons
A thymic peptide bioregulator developed by Vladimir Khavinson at the St. Petersburg Institute of Bioregulation and Gerontology. Thymalin is a complex of polypeptides extracted from the thymus gland that has been used clinically in Russia since the 1980s for immune restoration. Khavinson's research group reported that thymalin treatment in elderly patients was associated with reduced mortality over a 6-year follow-up period.
A thymic peptide that plays a central role in immune system regulation. Approved as a drug in over 35 countries (though not in the US) for hepatitis B and C treatment and as an immune booster.
Contains a mixture of thymic peptides that restore T-cell function and thymic output. Proposed to act through epigenetic mechanisms, reactivating genes involved in immune function that become silenced with aging. May promote thymic regeneration and restore the balance between T-helper and T-suppressor cells.
Enhances T-cell function, promotes dendritic cell maturation, and modulates cytokine production. Acts as an immune system regulator rather than a simple stimulant, helping to balance immune responses.
- Immune system restoration in elderly patients
- Post-infection immune recovery
- Anti-aging and longevity protocols
- Adjunct to cancer immunotherapy (in Russian clinical practice)
- Immune system support
- Chronic infection management
- Cancer adjunct therapy (in some countries)
- Post-illness recovery
- Autoimmune condition management
- Limited Western clinical data
- Most research from Russian institutions — peer review concerns
- Allergic reactions possible (animal-derived extract)
- Quality varies significantly between sources
- Generally well-tolerated in clinical use
- Injection site reactions
- Rare allergic reactions
- May interact with immunosuppressive drugs
Not FDA-approved or recognized. Used clinically in Russia and some CIS countries. No FDA category. Available only as a research peptide in the US. Khavinson's longevity claims, while published, have not been replicated in Western clinical trials.
Reclassified to Category 1 in February 2026 as part of the HHS announcement restoring compounding access. Not affected by the April 15, 2026 Category 2 removal action. Approved as Zadaxin in 35+ countries but not FDA-approved in the US. Available through licensed 503A compounding pharmacies with a physician prescription.
This comparison is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any peptide therapy.