Clopidogrel
| Evidence Level: L5 | Predicted Indications: 10 |
Table of Contents
Clopidogrel: From Acute Coronary Syndrome to Migraine Disorder
One-Sentence Summary
Clopidogrel is an antiplatelet drug originally used for acute coronary syndrome, intracranial embolism and ST-elevation myocardial infarction. The TxGNN model predicts it may be effective for migraine disorder, the best-supported of the top-ranked predictions. Currently 6 clinical trials (only 3 of which test the drug directly) and 21 publications relate to this direction, with direct drug evidence mostly from small or post-procedural studies.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Acute coronary syndrome, intracranial embolism, ST-elevation myocardial infarction (from the knowledge graph; no approved indication text is available in the Singapore licence records) |
| Predicted New Indication | Migraine disorder (the top-scored prediction, migraine with brainstem aura, is a subtype with weaker evidence; migraine disorder is the best-supported one) |
| TxGNN Prediction Score | 99.44% (migraine disorder); 99.44% for migraine with brainstem aura |
| Evidence Level | L1 on a conservative reading of the trial set; direct clopidogrel evidence is closer to L2 |
| Singapore Market Status | ✓ Marketed |
| Number of Registrations | 13 |
| Recommended Decision | Proceed with Guardrails (research-stage only) |
Why is This Prediction Reasonable?
Detailed mechanism of action data is not available in the data compiled for this report. Based on known pharmacology, clopidogrel is a P2Y12 platelet receptor antagonist. It is proven in preventing thrombotic events in coronary and cerebrovascular disease.
Migraine, particularly with aura, is associated with patent foramen ovale (PFO) and other right-to-left shunts. Proposed contributors include platelet hyperreactivity, release of vasoactive and pro-nociceptive mediators such as serotonin, and paradoxical microembolism. By inhibiting platelet activation, clopidogrel could reduce these triggers. Preclinical work also points to P2Y12 receptor involvement in migraine models (nitroglycerin-induced model in mice and microglial activation in chronic migraine).
Important caveats: the supporting evidence comes largely from PFO-associated migraine or migraine after septal defect closure, not from migraine in general. For the top-ranked subtype (migraine with brainstem aura), no trial is registered and the evidence is inferred from the broader migraine-with-aura literature.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT05546320 | Phase 2 | Completed | 1000 | COMPETE: anticoagulation vs antiplatelet vs migraine medication in migraine with PFO; the most direct clopidogrel-relevant trial |
| NCT00799045 | Phase 4 | Completed | 220 | CANOA: clopidogrel added to aspirin to prevent new-onset migraine after transcatheter ASD closure |
| NCT02938182 | Phase 4 | Unknown | 50 | Clopidogrel prophylaxis in migraine with right-to-left shunt; small, status unknown |
| NCT04946734 | Phase 3 | Active, not recruiting | 440 | SPRING: PFO closure vs medicine for migraine; the primary question is device vs drug |
| NCT00562289 | Phase 3 | Completed | 664 | PFO closure vs anticoagulants vs antiplatelets to prevent stroke recurrence; migraine is not the primary indication |
| NCT04100135 | NA | Terminated | 7 | Device study (GORE CARDIOFORM) in migraine; not a drug trial and uninformative |
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 42526943 | 2026 | RCT (multicentre, open label) | BMJ | Antithrombotic treatment for migraine prevention in patients with PFO |
| 26551304 | 2015 | RCT | JAMA | CANOA: clopidogrel plus aspirin vs aspirin alone for migraine after ASD closure |
| 32965476 | 2021 | RCT (1-year follow-up) | JAMA Cardiol | CANOA 1-year results after clopidogrel stopped at 3 months |
| 24836213 | 2014 | RCT (pilot) | Cephalalgia | Pilot randomised study of clopidogrel as migraine prophylaxis |
| 39989443 | 2025 | Systematic review | Headache | Role of antithrombotic drugs in migraine prevention |
| 40144614 | 2025 | Systematic review | Indian J Thorac Cardiovasc Surg | Incidence and management of new-onset headache after transcatheter ASD closure |
| 32848048 | 2020 | Cohort | J Investig Med | Clopidogrel 75 mg/day as add-on prophylaxis in drug-refractory migraine with PFO |
| 16103551 | 2005 | Cohort | Heart | Clopidogrel reduced migraine with aura after atrial shunt closure |
| 30478066 | 2018 | Retrospective review | Neurology | Off-label thienopyridine therapy in migraineurs with PFO |
| 30478067 | 2018 | Open-label pilot (related drug, ticagrelor) | Neurology | Ticagrelor in refractory migraine with PFO |
Singapore Market Information
There are 13 valid single-ingredient registrations; no approved indication text is recorded for any of them. The main ones are:
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| SIN09828P | PLAVIX TABLET 75 mg | Film-coated tablet | Not recorded |
| SIN13746P | Clopidogrel Sandoz Film Coated Tablet 75mg | Film-coated tablet | Not recorded |
| SIN14091P | GRIDOKLINE TABLETS 75MG | Film-coated tablet | Not recorded |
| SIN15153P | CLOPIVID TABLET 75MG | Tablet | Not recorded |
| SIN17130P | CLOPISWIFT FILM-COATED TABLET 75MG | Film-coated tablet | Not recorded |
All products are oral tablets (75 mg).
Safety Considerations
- Contraindications suggested by the knowledge graph (not label text): acute liver failure, hepatitis, blood coagulation disease, injury, thrombocytopenic purpura, active peptic ulcer disease, intracranial haemorrhage. These reflect bleeding risk, which must be weighed against benefit in a non-fatal condition such as migraine.
- Drug Interactions: 100 interactions were found. The major ones include:
- Proton pump inhibitors: rabeprazole, omeprazole, esomeprazole (Major); lansoprazole and pantoprazole (Moderate)
- Pioglitazone, loperamide, repaglinide (Major)
- Moderate: acetylsalicylic acid (aspirin), bupropion, morphine, cimetidine, clarithromycin
- Package insert warnings and contraindications were not available, so please refer to the package insert for full safety information.
Conclusion and Next Steps
Decision: Proceed with Guardrails
Rationale: Several randomised and observational studies suggest clopidogrel may reduce migraine, especially in patients with PFO or after septal defect closure, and the drug is widely marketed in Singapore. However, the evidence is mostly in selected populations, with small or pilot studies and mixed results, and the Phase 3 trials mainly compare PFO closure rather than clopidogrel. This is best treated as a research question, not a basis for routine use.
The other predictions are not supported: osteoarthritis, tendinitis, myositis fibrosa, idiopathic granulomatous myositis, rheumatoid arthritis, osteoarthritis susceptibility, pseudoachondroplasia and fibromyalgia all have little or no relevant evidence (Hold). For rheumatoid arthritis, the literature actually contains safety signals pointing the opposite way.
To proceed, the following is needed:
- Package insert warnings and contraindications from the HSA records, to allow safety screening
- Mechanism of action data
- Review of the full COMPETE results and the 2026 BMJ trial for clopidogrel-specific efficacy
- A defined target population (e.g., migraine with aura and PFO) with a bleeding-risk assessment
- Evidence specific to migraine with brainstem aura, if that subtype is pursued
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.