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Sulfadoxine pyrimethamine

Radboud University Medical Center · FDA-approved active Small molecule

Sulfadoxine-pyrimethamine is a fixed-dose combination of two antifolate drugs that inhibits dihydrofolate reductase and dihydropteroate synthase, blocking folate synthesis in parasites and preventing malaria and toxoplasmosis.

Sulfadoxine-pyrimethamine is a fixed-dose combination of two antifolate drugs that inhibits dihydrofolate reductase and dihydropteroate synthase, blocking folate synthesis in parasites and preventing malaria and toxoplasmosis. Used for Malaria (Plasmodium falciparum), Toxoplasmosis prophylaxis and treatment, Pneumocystis jirovecii pneumonia (PCP) prophylaxis.

At a glance

Generic nameSulfadoxine pyrimethamine
Also known asFansidar, SP, fansidar, IPTp-SP
SponsorRadboud University Medical Center
Drug classAntifolate antimalarial
TargetDihydrofolate reductase; dihydropteroate synthase
ModalitySmall molecule
Therapeutic areaInfectious Disease
PhaseFDA-approved

Mechanism of action

Sulfadoxine inhibits bacterial dihydropteroate synthase, while pyrimethamine inhibits dihydrofolate reductase in both parasites and bacteria. Together, they sequentially block folate metabolism, which is essential for nucleotide synthesis and parasite survival. This combination is particularly effective against Plasmodium falciparum (malaria) and Toxoplasma gondii.

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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