Thymalin
Immune
Also known as: Thymalin, Thymus polypeptide fraction, Khavinson thymus bioregulator
Either documented serious adverse events in humans, or effectively no retrievable evidence base. Dosing figures circulating for these compounds have no scientific foundation.
No rigorous published human pharmacokinetics. Thymalin is a peptide COMPLEX (mild acid extract of calf thymus), not a single defined molecule, so no single molecular weight or half-life exists. Literature traces overwhelmingly to the Khavinson (St. Petersburg) research lineage without independent Western replication.
No FDA/EMA-standardized dosing. Reported Russian clinical use is in the low-milligram range IM, but not verifiable against a regulated label at approved-host sources.
In-vitro/animal and Russian clinical reports concentrated in a single research lineage (Khavinson/Anisimov); minimal independent replication and essentially no modern pharmacokinetic data.
No boxed warning (unapproved). Product identity/purity is not regulated by a major agency; being an animal-tissue extract, immunogenicity and contamination are theoretical concerns. No controlled safety data at Western regulatory standards.