Skip to content
AMR Drug RepurposingSmart Screeningresearch prototype

Pyrimethamine

FDA-approved product (tablet, oral), marketed as Daraprim, Pyrimethamine.

Registered studies
50+
Lab records
9
Pathogens at ≥40%
3 of 4

Chemical structure

Chemical structure of Pyrimethamine
A drawing shows what the molecule is, not what it does.

Existing / approved use

Documented · FDA, WHO, ChEMBL

Approved for

  • Malaria
  • Toxoplasmosis

Indications ChEMBL records as approved, from FDA and DailyMed labels. Label ↗

WHO therapeutic group
Diaminopyrimidines
FDA pharmacologic class
Dihydrofolate Reductase Inhibitor Antimalarial FDA label ↗
Anti-infective classification
Classified as another kind of anti-infective (for example an antifungal, antiviral or antiparasitic medicine).WHO ATC P01BD01; WHO ATC P01BD51; FDA class Dihydrofolate Reductase Inhibitor Antimalarial

Repurposing investigation

This medicine is being investigated here for AI-predicted antimicrobial activity against MRSA, E. coli and M. tuberculosis. It was surfaced computationally for further investigation; it is not an established treatment for these infections.

AI-predicted activity

AI prediction · nothing measured
  • MRSA49.0% AI-predicted activityAt or above the ≥40% mark this site uses to surface candidates.
  • E. coli64.6% AI-predicted activityAt or above the ≥40% mark this site uses to surface candidates. This medicine was in the model's training data, so this is recall, not a new prediction.
  • K. pneumoniae11.3% AI-predicted activityBelow the ≥40% mark this site uses to surface candidates.
  • M. tuberculosis54.6% AI-predicted activityAt or above the ≥40% mark this site uses to surface candidates.

A model’s estimate of laboratory activity against each pathogen species. It is not clinical effectiveness.

Evidence

Clinical and experimental

Documented evidence

Clinical

50+registered studies name this medicine, for any condition. The registry search keeps the first 50, so there may be more. See them below.

Experimental

  • E. coli: measured active in 9 of 9 lab records
Open Pyrimethamine in ChEMBL Registered studies below
Show the 9 laboratory records, with sources

Loading records…

“Active” means the measured value reached this project’s laboratory cutoff (10 µM or stronger). A laboratory result does not show an effect in patients.

Docking

Computational · nothing measured

Dihydrofolate reductase ↗ (E. coli)

-7.1 kcal/mol

0better fit →-12

KPC-2 carbapenemase ↗ (K. pneumoniae)

-6.2 kcal/mol

0better fit →-12

Enoyl-ACP reductase (InhA) ↗ (M. tuberculosis)

-6.7 kcal/mol

0better fit →-12

Dihydrofolate reductase ↗ (MRSA)

-7.9 kcal/mol

0better fit →-12

AutoDock Vina, one experimentally solved protein per pathogen. This project’s screening target is -7.0 kcal/mol, its own mark rather than a universal cutoff. A docking score is a structural hypothesis, not proof of binding, and requires experimental validation.

Other medicines to investigate

AI prediction · nothing measured

Other repurposing candidates: approved medicines besides Pyrimethamine with AI-predicted activity ≥40% against the chosen pathogen, leaving out existing antimicrobials. They are computational candidates for further investigation, not alternatives and not recommendations.

Sorted by AI-predicted activity, high to low. The order is not a ranking of which medicine is better.

Registered studies

A registration describes a study; it does not establish a positive result.

  • Combining Latency Reversing Agents to Address the HIV Reservoir

    NCT07384624 · start 2026-04

    Registered record
    Registry ID
    NCT07384624
    Conditions
    HIV (Human Immunodeficiency Virus); HIV -1 Infection
    Interventions
    Pyrimethamine (PYR); Lenalidomide; Topiramate (drug)
    Study type
    INTERVENTIONAL
    Phase
    Phase 1 / Phase 2
    Registry status
    Not yet recruiting
    Start
    2026-04
    Completion
    2028-07
    Enrolment
    30

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionHIV (Human Immunodeficiency Virus); HIV -1 Infection
    InterventionPyrimethamine (PYR); Lenalidomide; Topiramate (drug)
    PhasePhase 1 / Phase 2
    Registry statusNot yet recruiting

  • Preventing Malaria in School Children to Protect the Whole Community in Rural Blantyre District, Malawi

    NCT06083688 · start 2024-10-14

    Registered record
    Registry ID
    NCT06083688
    Conditions
    Malaria,Falciparum; Anemia in Children
    Interventions
    Dihydroartemisinin-Piperaquine; Chloroquine; Sulfadoxine-pyrimethamine-amodiaquine
    Study type
    INTERVENTIONAL
    Phase
    Phase 4
    Registry status
    Completed
    Start
    2024-10-14
    Completion
    2026-01-14
    Enrolment
    788

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionMalaria,Falciparum; Anemia in Children
    InterventionDihydroartemisinin-Piperaquine; Chloroquine; Sulfadoxine-pyrimethamine-amodiaquine
    PhasePhase 4
    Registry statusCompleted

  • Bioequivalence Study of Sulfadoxine/Pyrimethamine 500/25 mg Dispersible Tablet

    NCT06522763 · start 2024-07

    Registered record
    Registry ID
    NCT06522763
    Conditions
    Fasting
    Interventions
    Sulfadoxine 500 MG / Pyrimethamine 25 MG dispersible tablets.; Sulfadoxine 500 MG / Pyrimethamine 25 MG dispersible tablets in SPAQ
    Study type
    INTERVENTIONAL
    Phase
    Phase 1
    Registry status
    Unknown
    Start
    2024-07
    Completion
    2024-09
    Enrolment
    46

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionFasting
    InterventionSulfadoxine 500 MG / Pyrimethamine 25 MG dispersible tablets.; Sulfadoxine 500 MG / Pyrimethamine 25 MG dispersible tablets in SPAQ
    PhasePhase 1
    Registry statusUnknown

  • Eggs for Gut Health

    NCT06002438 · start 2023-10-09

    Registered record
    Registry ID
    NCT06002438
    Conditions
    Moderate Acute Malnutrition; Stunting; Environmental Enteric Dysfunction; Severe Acute Malnutrition
    Interventions
    Whole egg powder; Corn powder; Supercereal Plus; Micronutrient sprinkles; Sulfadoxine pyrimethamine
    Study type
    INTERVENTIONAL
    Phase
    Not applicable
    Registry status
    Completed
    Start
    2023-10-09
    Completion
    2024-12-19
    Enrolment
    461

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionModerate Acute Malnutrition; Stunting; Environmental Enteric Dysfunction; Severe Acute Malnutrition
    InterventionWhole egg powder; Corn powder; Supercereal Plus; Micronutrient sprinkles +1 more
    PhaseNot applicable
    Registry statusCompleted

  • Perennial Malaria Chemoprevention (PMC) in Côte d'Ivoire

    NCT05856357 · start 2023-08-11

    Registered record
    Registry ID
    NCT05856357
    Conditions
    Malaria; Anemia
    Interventions
    Sulfadoxine pyrimethamine
    Study type
    OBSERVATIONAL
    Phase
    Not recorded
    Registry status
    Completed
    Start
    2023-08-11
    Completion
    2025-12-31
    Enrolment
    1,381

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionMalaria; Anemia
    InterventionSulfadoxine pyrimethamine
    PhaseNot recorded
    Registry statusCompleted

  • Chemoprevention Efficacy Study Nigeria

    NCT05979896 · start 2023-07-28

    Registered record
    Registry ID
    NCT05979896
    Conditions
    Malaria
    Interventions
    Standard age based SPAQ administration for SMC
    Study type
    INTERVENTIONAL
    Phase
    Phase 4
    Registry status
    Unknown
    Start
    2023-07-28
    Completion
    2024-05-15
    Enrolment
    800

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionMalaria
    InterventionStandard age based SPAQ administration for SMC
    PhasePhase 4
    Registry statusUnknown

  • Perennial Malaria Chemoprevention (PMC) in Cameroon

    NCT05889052 · start 2023-07-19

    Registered record
    Registry ID
    NCT05889052
    Conditions
    Anemia; Malaria
    Interventions
    Sulfadoxine pyrimethamine
    Study type
    OBSERVATIONAL
    Phase
    Not recorded
    Registry status
    Completed
    Start
    2023-07-19
    Completion
    2025-12-31
    Enrolment
    2,138

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionAnemia; Malaria
    InterventionSulfadoxine pyrimethamine
    PhaseNot recorded
    Registry statusCompleted

  • Community-based, Controlled, Open-label, Cluster-randomized Trial for the Reduction of Chronic Malnutrition in Children Under Two Years of Age, With Three Intervention Arms Grouped by Clusters, in Two Provinces in Southern Angola, Huíla and Cunene.

    NCT05571280 · start 2022-10-10

    Registered record
    Registry ID
    NCT05571280
    Conditions
    Malnutrition, Child
    Interventions
    Nutritional Supplementation; Money transfers; Standard intervention
    Study type
    INTERVENTIONAL
    Phase
    Not applicable
    Registry status
    Active not recruiting
    Start
    2022-10-10
    Completion
    2026-07
    Enrolment
    1,423

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionMalnutrition, Child
    InterventionNutritional Supplementation; Money transfers; Standard intervention
    PhaseNot applicable
    Registry statusActive not recruiting

  • Controlled Human Malaria Infection Transmission Model - Phase A

    NCT04280692 · start 2022-08-22

    Registered record
    Registry ID
    NCT04280692
    Conditions
    Malaria,Falciparum
    Interventions
    PfSPZ Challenge; Sulfadoxine-Pyrimethamine; Piperaquine; Artemether lumefantrine; Primaquine
    Study type
    INTERVENTIONAL
    Phase
    Phase 1 / Phase 2
    Registry status
    Suspended
    Start
    2022-08-22
    Completion
    2026-08
    Enrolment
    44

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionMalaria,Falciparum
    InterventionPfSPZ Challenge; Sulfadoxine-Pyrimethamine; Piperaquine; Artemether lumefantrine +1 more
    PhasePhase 1 / Phase 2
    Registry statusSuspended

  • Bioequivalence Study of Sulfadoxine/ Pyrimethamine Tablets in Healthy Subjects Under Fasting Conditions

    NCT04577469 · start 2020-12

    Registered record
    Registry ID
    NCT04577469
    Conditions
    Bioequivalence
    Interventions
    Maldox tablets; G-COSPE® tablets
    Study type
    INTERVENTIONAL
    Phase
    Phase 1
    Registry status
    Unknown
    Start
    2020-12
    Completion
    2020-12
    Enrolment
    52

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionBioequivalence
    InterventionMaldox tablets; G-COSPE® tablets
    PhasePhase 1
    Registry statusUnknown

  • Pyrimethamine for Intermediate/High-risk Myelodysplastic Syndromes (MDS)

    NCT03057990 · start 2019-09-11

    Registered record
    Registry ID
    NCT03057990
    Conditions
    Myelodysplastic Syndromes
    Interventions
    Pyrimethamine
    Study type
    INTERVENTIONAL
    Phase
    Phase 1
    Registry status
    Withdrawn
    Start
    2019-09-11
    Completion
    2021-06-29
    Enrolment
    0

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionMyelodysplastic Syndromes
    InterventionPyrimethamine
    PhasePhase 1
    Registry statusWithdrawn

  • Sanaria PfSPZ Challenge With Pyrimethamine or Chloroquine Chemoprophylaxis Vaccination (PfSPZ-CVac Approach): A Randomized Double Blind Placebo Controlled Phase I/II Trial to Determine Safety and Protective Efficacy Against Natural Plasmodium Falcipa...

    NCT03952650 · start 2019-05-23

    Registered record
    Registry ID
    NCT03952650
    Conditions
    Malaria
    Interventions
    Chloroquine Phosphate; PfSPZ Challenge; Pyrimethamine; Coartem; ibuprofen
    Study type
    INTERVENTIONAL
    Phase
    Phase 1 / Phase 2
    Registry status
    Completed
    Start
    2019-05-23
    Completion
    2021-02-10
    Enrolment
    252

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionMalaria
    InterventionChloroquine Phosphate; PfSPZ Challenge; Pyrimethamine; Coartem +1 more
    PhasePhase 1 / Phase 2
    Registry statusCompleted

  • Monthly Versus Two Doses of Ante-Natal Intermittent Preventive Treatment With Sulphadoxine-Pyrimethamine

    NCT03599596 · start 2018-09-01

    Registered record
    Registry ID
    NCT03599596
    Conditions
    Malaria
    Interventions
    Sulphadoxine-pyrimethamine; Sulphadoxine-pyrimethamine
    Study type
    INTERVENTIONAL
    Phase
    Phase 1
    Registry status
    Unknown
    Start
    2018-09-01
    Completion
    2019-02-01
    Enrolment
    136

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionMalaria
    InterventionSulphadoxine-pyrimethamine; Sulphadoxine-pyrimethamine
    PhasePhase 1
    Registry statusUnknown

  • TIPTOP Sulfadoxine-pyrimethamine (SP) Drug Resistance Study

    NCT03998839 · start 2018-03-05

    Registered record
    Registry ID
    NCT03998839
    Conditions
    Malaria in Pregnancy
    Interventions
    Community distribution of Sulfadoxine-pyrimethamine (SP)
    Study type
    OBSERVATIONAL
    Phase
    Not recorded
    Registry status
    Completed
    Start
    2018-03-05
    Completion
    2021-11-30
    Enrolment
    7,200

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionMalaria in Pregnancy
    InterventionCommunity distribution of Sulfadoxine-pyrimethamine (SP)
    PhaseNot recorded
    Registry statusCompleted

  • Enhancing Preventive Therapy of Malaria In Children With Sickle Cell Anemia in East Africa (EPiTOMISE)

    NCT03178643 · start 2018-01-23

    Registered record
    Registry ID
    NCT03178643
    Conditions
    Malaria,Falciparum
    Interventions
    Proguanil Oral Tablet; Sulfadoxine/Pyrimethanine-Amodiaquine (SP-AQ); Dihydroartemisinin-Piperaquine (DP)
    Study type
    INTERVENTIONAL
    Phase
    Phase 4
    Registry status
    Completed
    Start
    2018-01-23
    Completion
    2020-12-16
    Enrolment
    246

    As stored from ClinicalTrials.gov. Registration describes a study; it does not mean the study worked.

    ConditionMalaria,Falciparum
    InterventionProguanil Oral Tablet; Sulfadoxine/Pyrimethanine-Amodiaquine (SP-AQ); Dihydroartemisinin-Piperaquine (DP)
    PhasePhase 4
    Registry statusCompleted