For clinicians
Thymopentin for prescribers: status, evidence and what FDA has said
A neutral reference. It reports Thymopentin's regulatory status, the quality of its human evidence and what FDA has said about it. It does not suggest a dose, a protocol or a source.
Status reviewed 2026-10-01 · By the Grey Peptides Editorial Board · Regulatory fields generated from our tracker
| Also known as | — |
| FDA approval | Not FDA-approved; approved in some countries outside the US |
| Compounding (503A) | Not compoundable (nomination withdrawn; on no FDA list) |
| Outsourcing (503B) | No 503B status recorded |
| WADA 2026 List | Unsettled (S0 may apply) |
| WADA 2027 List | Unsettled (S0 may apply) |
| Evidence grade | Medium |
| Status reviewed | 2026-10-01 |
What FDA has said
FDA has not placed Thymopentin on its list of bulk substances that may present significant safety risks (current as of 2026-04-22), and this page has no other FDA review of it to report.
Monitoring: what the literature does and does not say
- No label. Thymopentin has no FDA-approved label, and therefore no labelled guidance on monitoring.
- Not on FDA's safety-risks list. Thymopentin does not appear on FDA's list of bulk substances that may present significant safety risks (current as of 2026-04-22). That is an absence of a listing, not a finding of safety.
These are gaps, not a monitoring schedule. This page does not supply one, and for a compound in this position the human evidence would not support one.
Compounding: where it stands
Today's position for Thymopentin: Not compoundable (nomination withdrawn; on no FDA list). An FDA advisory committee's vote is a non-binding recommendation; until FDA acts, a vote does not change what may be compounded. Our explainer on the 503A and 503B categories sets out what each status means, and the regulatory tracker is updated as FDA acts.
The evidence
A synthetic pentapeptide (Arg-Lys-Asp-Val-Tyr), residues 32 to 36 of the thymic hormone thymopoietin, studied as an immune modulator and sold as Timunox. Small 1980s and 1990s trials found modest benefits in atopic dermatitis and rheumatoid arthritis.
The encyclopedia entry lists the human and animal studies we hold, each with its PMID.
What this page leaves out
Doses, regimens, cycle lengths and sources. That is deliberate. A reference that reports status and evidence is useful only if it is not also a protocol, and for a compound in this position there is no approved one to report.
Sources
- US Food and Drug Administration. Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks. Content current as of 2026-04-22; read 2026-10-01. FDA
- Grey Peptides regulatory tracker, row for Thymopentin, reviewed 2026-10-01. Tracker · dataset
- World Anti-Doping Agency. Prohibited List 2027, dated August 26, 2026, in force January 1, 2027. WADA
This page is a reference for qualified professionals. It is not medical advice, it does not recommend any treatment, and it is not a substitute for the prescriber's own judgement and their state and federal obligations.
Others in this group: AOD-9604 · Cathelicidin (LL-37) · Cerebrolysin · CJC-1295 · Dihexa · GHK-Cu (injectable) · GHRP-6 · Hexarelin · Ipamorelin · Melanotan II · MK-677 (ibutamoren) · Noopept · PEG-MGF · Pralmorelin (GHRP-2) · Selank · Sermorelin · Tesofensine · Thymosin α-1