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AMR Drug RepurposingSmart Screeningresearch prototype

Zafirlukast

FDA-approved product (tablet, oral), marketed as Accolate, Zafirlukast.

Registered studies
6
Lab records
0
Pathogens at ≥40%
3 of 4

Chemical structure

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

Existing / approved use

Documented · FDA, WHO, ChEMBL

Approved for

  • Airway obstruction
  • Asthma

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

WHO therapeutic group
Leukotriene receptor antagonists
FDA pharmacologic class
Leukotriene Receptor Antagonist FDA label ↗
Anti-infective classification
Not classified as an anti-infective.

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
  • MRSA58.8% AI-predicted activityAt or above the ≥40% mark this site uses to surface candidates.
  • E. coli45.9% AI-predicted activityAt or above the ≥40% mark this site uses to surface candidates.
  • K. pneumoniae31.0% AI-predicted activityBelow the ≥40% mark this site uses to surface candidates.
  • M. tuberculosis63.3% 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

6registered studies name this medicine, for any condition. See them below.

Experimental

No evidence found

No laboratory measurement against the four pathogens in the ChEMBL records loaded here.

Open Zafirlukast in ChEMBL Registered studies below

Docking

Computational · nothing measured

Dihydrofolate reductase ↗ (E. coli)

Not yet docked: queued in the docking rundetails

KPC-2 carbapenemase ↗ (K. pneumoniae)

Not yet docked: queued in the docking rundetails

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

Not yet docked: queued in the docking rundetails

Dihydrofolate reductase ↗ (MRSA)

Not yet docked: queued in the docking rundetails

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 Zafirlukast 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.

  • Crossover Study of Zafirlukast in Preventing Allergen-induced Signs and Symptoms in Response to Cat Dander Challenge

    NCT06069063 · start 2025-12-05

    Registered record
    Registry ID
    NCT06069063
    Conditions
    Allergy to Cats
    Interventions
    Zafirlukast
    Study type
    INTERVENTIONAL
    Phase
    Phase 2
    Registry status
    Not yet recruiting
    Start
    2025-12-05
    Completion
    2026-07
    Enrolment
    12

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

    ConditionAllergy to Cats
    InterventionZafirlukast
    PhasePhase 2
    Registry statusNot yet recruiting

  • The Efficacy of Leukotriene Inhibitor in Adult Patients With Moderate SARS-COV-2 Symptoms (COVID19)

    NCT04871828 · start 2021-02-28

    Registered record
    Registry ID
    NCT04871828
    Conditions
    Moderate Covid19
    Interventions
    Leukotriene Receptor Antagonist; Placebo
    Study type
    INTERVENTIONAL
    Phase
    Phase 3
    Registry status
    Unknown
    Start
    2021-02-28
    Completion
    2021-12
    Enrolment
    66

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

    ConditionModerate Covid19
    InterventionLeukotriene Receptor Antagonist; Placebo
    PhasePhase 3
    Registry statusUnknown

  • Zafirlukast in Treatment of Marker Relapsed Ovarian Cancer

    NCT04339140 · start 2020-06-24

    Registered record
    Registry ID
    NCT04339140
    Conditions
    Ovarian Cancer
    Interventions
    Zafirlukast
    Study type
    INTERVENTIONAL
    Phase
    Phase 2
    Registry status
    Completed
    Start
    2020-06-24
    Completion
    2024-12-31
    Enrolment
    5

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

    ConditionOvarian Cancer
    InterventionZafirlukast
    PhasePhase 2
    Registry statusCompleted

  • Breast Capsular Contracture Following Post-Mastectomy Reconstruction in Women Treated With the Leukotriene Inhibitor Zafirlukast: A Phase II Trial

    NCT02950480 · start 2017-03-13

    Registered record
    Registry ID
    NCT02950480
    Conditions
    Breast Cancer
    Interventions
    zafirlukast; Standard of Care (no intervention)
    Study type
    INTERVENTIONAL
    Phase
    Phase 2
    Registry status
    Terminated
    Start
    2017-03-13
    Completion
    2018-12-20
    Enrolment
    4

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

    ConditionBreast Cancer
    Interventionzafirlukast; Standard of Care (no intervention)
    PhasePhase 2
    Registry statusTerminated

  • A Study Evaluating the Persistency of Response With or Without Xolair (Omalizumab) After Long-term Therapy

    NCT01125748 · start 2010-05

    Registered record
    Registry ID
    NCT01125748
    Conditions
    Allergic Asthma
    Interventions
    Omalizumab; Placebo; Asthma therapies
    Study type
    INTERVENTIONAL
    Phase
    Phase 4
    Registry status
    Completed
    Start
    2010-05
    Completion
    2013-08
    Enrolment
    176

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

    ConditionAllergic Asthma
    InterventionOmalizumab; Placebo; Asthma therapies
    PhasePhase 4
    Registry statusCompleted

  • Bioequivalence Study of Zafirlukast Tablets 20 mg of Dr. Reddy's Laboratories Limited Under Fasting Condition

    NCT01283061 · start 2007-12

    Registered record
    Registry ID
    NCT01283061
    Conditions
    Healthy
    Interventions
    Zafirlukast
    Study type
    INTERVENTIONAL
    Phase
    Phase 1
    Registry status
    Completed
    Start
    2007-12
    Completion
    2008-01
    Enrolment
    44

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

    ConditionHealthy
    InterventionZafirlukast
    PhasePhase 1
    Registry statusCompleted