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Leflunomide(LEF)

Nanjing Children's Hospital · FDA-approved active Small molecule

Leflunomide inhibits dihydroorotate dehydrogenase, an enzyme required for pyrimidine synthesis, thereby suppressing T-cell and B-cell proliferation.

Leflunomide inhibits dihydroorotate dehydrogenase, an enzyme required for pyrimidine synthesis, thereby suppressing T-cell and B-cell proliferation. Used for Rheumatoid arthritis, Active psoriatic arthritis, Active ankylosing spondylitis.

At a glance

Generic nameLeflunomide(LEF)
SponsorNanjing Children's Hospital
Drug classImmunosuppressant; DHODH inhibitor
TargetDihydroorotate dehydrogenase (DHODH)
ModalitySmall molecule
Therapeutic areaImmunology; Rheumatology
PhaseFDA-approved

Mechanism of action

Leflunomide's active metabolite, teriflunomide, reversibly inhibits dihydroorotate dehydrogenase (DHODH), a mitochondrial enzyme critical for de novo pyrimidine nucleotide synthesis. This selectively impairs the proliferation of activated lymphocytes, which depend heavily on de novo pyrimidine synthesis, leading to immunosuppression. The drug is used to reduce inflammation and slow disease progression in autoimmune conditions.

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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