Thymalin
Thymalin, a peptide. A thymus-derived POLYPEPTIDE PREPARATION, not a single molecule: PMID:33237528 verbatim, "Thymalin is a polypeptide complex isolated from the…
A thymus-derived POLYPEPTIDE PREPARATION, not a single molecule: PMID:33237528 verbatim, "Thymalin is a polypeptide complex isolated from the thymus and regulating the functions of the immune system", and PMID:37686182 verbatim, "Thymalin is an immunomodulatory drug containing a polypeptide extract of thymus". Two constituents are named as the active species — PMID:37686182, "KE and EW dipeptides are active substances of Thymalin" — where KE is Lys-Glu, the same dipeptide this catalog holds as `vilon`. Reported action is restoration of the T-cell arm: it pushes human haematopoietic stem cells toward mature T lymphocytes, and "Thymalin and EW and KE dipeptides reduced the synthesis of IL-1β, IL-6, and TNF-α cytokines in human peripheral blood mononuclear cells by 1.4-6.0 times" (PMID:37686182).
NO MOLECULAR WEIGHT IS STORED, AND THE REASON IS A TRAP OTHERS WILL HIT. Querying PubChem for `Thymalin` returns CID 3085284 (C33H54N12O15, 858.9) — but that CID`s synonym list, fetched 2026-09-26, is "Nonathymulin", "Nonathymulin [INN]", "Thymic factor", "Thymulin (pig peptide moiety)", CAS 63958-90-7, and the spelled-out nonapeptide pGlu-Ala-Lys-Ser-Gln-Gly-Gly-Ser-Asn. IT IS THYMULIN, a defined nonapeptide, which merely carries "Thymalin" in its synonym list. Storing 858.9 here would be a wrong-molecule mass. A multi-constituent preparation stores none, per HYGIENE gate 3 and the pentosan-polysulfate precedent. composition[] IS ALSO NOT AUTHORED: only two constituents are named (KE, EW) and no abstract gives an amount, while composition[].mg_per_g_extract is a required positive number — see the GAPS row. HUMAN DATA ARE CLINICAL OUTCOMES, NOT PK: PMID:33575961 (severe COVID-19, "The addition of thymalin to standard therapy accelerated the decline in both these indicators and the indicators of the T cell system"), PMID:31889704 (68 children, secretory otitis media). A DEFECT IN A PAPER, RECORDED SO NOBODY STORES ITS NUMBERS: PMID:36169363 reports hospital mortality as "40,9; 28,4 and 20,6%" in its English abstract while the Russian abstract in the same efetch response gives 40,9; 28,8 and 16,2% — THE TWO LANGUAGE VERSIONS OF ONE ABSTRACT DISAGREE ON TWO OF THREE NUMBERS, so none of them is storable without full text. A DOSE THAT MUST NOT BE IMPORTED: PMID:24734422 prints "0.005 mg / kg and 0.05 mg /kg" for TINROSTIM, a comparator, not for Thymalin. DISTINCT FROM `thymosin-alpha-1`, already in this catalog, which is a defined 28-residue peptide with real PK.
Sources: PMID:33237528, PMID:37686182, PMID:33575961, PMID:31889704, PMID:36169363, PMID:15605441