Immune · Investigational
Splenopentin
No lawful US pathway
01 · Overview
Splenopentin (SP-5) is a synthetic pentapeptide (Arg-Lys-Glu-Val-Tyr) corresponding to residues 32 to 36 of the splenic protein splenin (PMID 2292457). It differs from the thymic peptide thymopentin (Arg-Lys-Asp-Val-Tyr) by a single amino acid (PMID 9638477).
Most studies used an acetylated form, diacetyl-splenopentin (DAc-SP-5, also called BCH 069). It was studied as an immunomodulator intended to provide targeted immune enhancement without the variability of whole-organ extracts.
02 · Research summary & key findings
In sublethally irradiated mice, diacetyl-splenopentin accelerated recovery of blood-forming and immune function (PMID 2292457) and led to earlier and higher antibody production, and it increased phagocytic capacity of human granulocytes in vitro (PMID 2667491). Small East German human studies found intravenous, but not subcutaneous, treatment reduced hay fever symptoms compared with placebo (PMID 2251976), while an uncontrolled study in 8 patients with psoriatic arthritis reported pain relief but radiographic worsening, concluding it was not a sufficient treatment (PMID 2365110). No further clinical development has been reported.
03 · Regulatory status
Splenopentin is in the investigational stage. While preclinical and early-phase data exist, it has not received regulatory approval for clinical use in the United States.
No lawful pathway today
Splenopentin is not FDA-approved and does not currently have a lawful prescription or compounding pathway in the United States, so we do not sell it and will not book a consultation for it. That can change: in 2026 FDA began reviewing several peptides for compounding.
See the 1 FDA-approved compound in Immune
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04 · Administration routes
- Subcutaneous injection
- Intravenous
References
- [1]Clinical, biochemical and immunological effectiveness of diacetyl-splenopentin (BCH 069) in hay fever Allergol Immunopathol (Madr), 1990. PMID 2251976
- [2]Splenopentin (DAc-SP-5) accelerates the restoration of myelopoietic and immune systems after sublethal radiation in mice Int J Immunopharmacol, 1990. PMID 2292457
- [3][Therapeutic use of splenopentin (DA SP-5) in patients with psoriasis arthropathica] Dermatol Monatsschr, 1990. PMID 2365110
- [4]Splenopentin--influence on antibody formation in immunosuppressed animals and on phagocytic capability of human granulocytes Arch Geschwulstforsch, 1989. PMID 2667491
- [5]Thymopentin and splenopentin as immunomodulators. Current status Immunol Res, 1998. PMID 9638477
Primary literature
- PubMed: "Splenopentin"
Peer-reviewed literature indexed by the National Library of Medicine.
- ClinicalTrials.gov: "Splenopentin"
Registered interventional and observational studies, including status and phase.
- PubChem: "Splenopentin"
Chemical structure, molecular properties, and bioactivity data.
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