Immune Modulation Research
Research Only
Thymalin
Also known as: Timalin, Thymalin extract, calf thymus extract
Thymalin is a peptide mixture extracted from calf thymus, used as a medicine in Russia. Studied in immune-cell research.
Research overview
Thymalin (also written Timalin) is not a single peptide but a mixture of peptides extracted from calf thymus, the gland where T cells mature. It was developed by Morozov, Khavinson and colleagues in St Petersburg and has been used as a medicine in Russia (Morozov and Khavinson, 1997). Its developers report two dipeptides, Lys-Glu and Glu-Trp, as active parts. There is a large clinical literature, mostly in Russian and Ukrainian journals, across many conditions. The best-known report followed 266 older people for 6 to 8 years and described lower death rates in groups given Thymalin, the pineal extract Epithalamin or both than in controls (Khavinson and Morozov, 2003). During the COVID-19 pandemic, hospital studies in Russia measured blood cell counts and clotting markers when Thymalin was added to standard care. In lab work it changed markers of blood stem cell maturation and lowered inflammatory signals in stimulated human blood cells.
Most studies come from the developers and their partners, and the abstracts give few details of randomisation or blinding. We found no large randomised placebo-controlled trials. It is not a licensed medicine in the UK. Supplied for laboratory research use only.
Mechanism of action
Thymalin is a mixture, so it has no single target. In lab studies it shifted human blood stem cells towards mature T cells, measured as more CD28 and less CD44 and CD117 on the cell surface (Khavinson et al., 2020), and lowered IL-1β, IL-6 and TNF-α, signalling proteins of inflammation, in stimulated human blood cells. Its developers attribute these effects to the dipeptides Lys-Glu and Glu-Trp, which their computer modelling suggests could bind DNA. This evidence comes from cell work by the developers' group.