Last reviewed · How we verify

Pyrimethamine/Sulfadiazine

Assistance Publique - Hôpitaux de Paris · Phase 3 active Small molecule

Pyrimethamine and sulfadiazine work synergistically to inhibit folate metabolism in parasites and bacteria, blocking nucleotide synthesis and preventing microbial replication.

Pyrimethamine and sulfadiazine work synergistically to inhibit folate metabolism in parasites and bacteria, blocking nucleotide synthesis and preventing microbial replication. Used for Toxoplasmosis, including cerebral toxoplasmosis in immunocompromised patients, Toxoplasma gondii infection prophylaxis and treatment.

At a glance

Generic namePyrimethamine/Sulfadiazine
Also known asPyrimethamine = Malocide®, Sulfadiazine = Adiazine®
SponsorAssistance Publique - Hôpitaux de Paris
Drug classAntiparasitic/Antimicrobial combination
TargetDihydrofolate reductase (pyrimethamine); Dihydropteroate synthase (sulfadiazine)
ModalitySmall molecule
Therapeutic areaInfectious Disease
PhasePhase 3

Mechanism of action

Pyrimethamine inhibits dihydrofolate reductase in parasites, while sulfadiazine inhibits bacterial folate synthesis by blocking dihydropteroate synthase. Together, they create a dual blockade of the folate pathway, making them particularly effective against Toxoplasma gondii and other intracellular pathogens. This combination is the standard treatment for toxoplasmosis, especially in immunocompromised patients.

Approved indications

Common side effects

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

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

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape: