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Cyclosporin A (CsA)

Peking Union Medical College Hospital · FDA-approved active Small molecule

Cyclosporin A inhibits calcineurin phosphatase, blocking T-cell activation and proliferation by preventing IL-2 transcription.

Cyclosporin A inhibits calcineurin phosphatase, blocking T-cell activation and proliferation by preventing IL-2 transcription. Used for Organ transplant rejection prophylaxis (kidney, heart, liver, pancreas), Autoimmune diseases including rheumatoid arthritis, psoriasis, and atopic dermatitis, Graft-versus-host disease (GVHD) prevention and treatment.

At a glance

Generic nameCyclosporin A (CsA)
Also known asSandimmun Optoral
SponsorPeking Union Medical College Hospital
Drug classCalcineurin inhibitor
TargetCalcineurin (protein phosphatase 2B)
ModalitySmall molecule
Therapeutic areaImmunology
PhaseFDA-approved

Mechanism of action

Cyclosporin A binds to cyclophilin, and this complex inhibits calcineurin (protein phosphatase 2B), which normally dephosphorylates NFAT transcription factors. By blocking NFAT nuclear translocation, CsA prevents IL-2 and other cytokine production essential for T-cell activation and clonal expansion. This potent immunosuppressive effect makes it valuable in transplantation and autoimmune diseases.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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