Peptide library / Immune & defense / Cyclosporine
Cyclosporine
An 11 amino acid cyclic peptide from a soil fungus that made organ transplantation routine.
Effects studied or claimed
What it is used or promoted for, and where each effect has actually been seen
- Prevent rejection after organ transplantFDA approved
- Psoriasis and rheumatoid arthritisFDA approved
- Dry eyeFDA approved
How it is thought to work
Cyclosporine binds cyclophilin and blocks calcineurin, which shuts down T cell activation.
What the evidence shows
Introduced in the early 1980s, it sharply improved transplant survival.
Safety and unknowns
Kidney damage, high blood pressure and infection risk are the main concerns.
Regulatory status
FDA-approved as Sandimmune in 1983.
Regulatory status changes quickly. This entry was last reviewed on 27 October 2026. Confirm current status with the FDA before relying on it.
More in Immune & defense
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FDA-approvedA long-acting lipoglycopeptide antibiotic given as one or two infusions.
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FDA-approvedA cyclic lipopeptide antibiotic from soil bacteria for serious skin and bloodstream infections.
Colistin
FDA-approvedA last-resort polypeptide antibiotic for highly resistant Gram-negative infections.
General information, not medical advice. Do not buy or inject unregulated peptides.