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All peptides
ImmuneResearch Phase

Splenopentin

Subcutaneous injection, Intravenous
Written by Peptide Association Editorial TeamMedically reviewed by Ian Justl Ellis, MD, CPTLast reviewed Editorial policy

Overview

Splenopentin is a synthetic pentapeptide (Arg-Lys-Glu-Val-Tyr) corresponding to residues 32 to 36 of the splenic hormone splenin. It modulates immune cell function by enhancing macrophage activity and stimulating antibody production.

Mechanism of Action

The therapeutic rationale is to provide targeted immune enhancement without whole-organ extract variability.

Research Summary & Key Findings

Preclinical studies in rodents demonstrated increased phagocytic activity and antibody titers following splenopentin administration. There is limited published clinical trial data, and the peptide remains primarily a research tool for understanding splenic immunomodulation.

Clinical Status

Research Phase

Splenopentin is in the research phase with limited clinical data in humans. Current evidence is primarily derived from preclinical (animal or in vitro) studies.

Administration Routes

Subcutaneous injectionIntravenous

References

Primary literature

Study-level citations for this compound are being verified against the primary sources before publication. The database queries above return the current indexed literature in the meantime.

Related Peptides in Immune

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 there is nothing for us to sell you here and no consultation to book. That can change: eight peptides moved back to a lawful pathway in February 2026.

Tell me if the status changes

One email, only if this compound's regulatory standing actually moves. Not a newsletter, not a sales sequence.

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Disclaimer: This information is provided for educational and research purposes only. It is not intended as medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before starting any peptide therapy. The Peptide Association does not endorse or recommend any specific treatment protocol. See our editorial policy for how this content is produced and reviewed.