Epoprostenol
| 證據等級: L5 | 預測適應症: 10 個 |
目錄
Epoprostenol: From Pulmonary Arterial Hypertension to Trigeminal Autonomic Cephalalgia
One-Sentence Summary
Epoprostenol (prostacyclin, PGI₂) is a synthetic prostaglandin vasodilator established globally for pulmonary arterial hypertension, with no current registration in Singapore. The TxGNN model predicts it may be effective for Trigeminal Autonomic Cephalalgia (TAC) with a prediction score of 98.41%, but this is supported by only 0 clinical trials and 2 publications — and critically, the available mechanistic evidence points in the opposite direction of a therapeutic use.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not registered in Singapore (established globally for pulmonary arterial hypertension) |
| Predicted New Indication | Trigeminal Autonomic Cephalalgia |
| TxGNN Prediction Score | 98.41% |
| Evidence Level | L4 |
| Singapore Market Status | Not marketed |
| Number of Registrations | 0 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available in the evidence pack. Based on known pharmacology, Epoprostenol is a synthetic prostacyclin (PGI₂) that binds IP (prostacyclin) receptors to elevate intracellular cAMP, producing vasodilation and antiplatelet effects. Its established clinical use — in pulmonary arterial hypertension — exploits this vasodilatory property to reduce pulmonary vascular resistance.
Trigeminal Autonomic Cephalalgia (TAC) is a family of severe unilateral headache disorders (including cluster headache, paroxysmal hemicrania, and SUNCT), characterised by autonomic features such as lacrimation, rhinorrhoea, and ptosis. The TxGNN model assigns a high score of 98.41%, which most likely reflects the well-documented co-occurrence of PGI₂ and headache disorders in the biomedical literature and knowledge graph — not a genuine therapeutic signal.
⚠️ Reverse Mechanism Warning: Research from the 1980s observed elevated PGI₂ metabolites during cluster headache attacks. The sole directly relevant publication (PMID 7026501) explored the effect of infused prostacyclin in cluster headache patients — with results suggesting PGI₂ may precipitate rather than relieve attacks. There is no evidence that exogenous Epoprostenol ameliorates TAC. The TxGNN score of 98.41% is assessed as a false positive driven by disease-drug co-occurrence in the knowledge graph.
Clinical Trial Evidence
Currently no related clinical trials registered for Epoprostenol in trigeminal autonomic cephalalgia.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 7026501 | 1981 | Clinical Study / Case Series | Headache | Examined the effect of infused prostacyclin in migraine and cluster headache patients; results do not support a therapeutic benefit and may reflect a precipitating effect |
| 3937967 | 1985 | Review / Mechanistic | Neurologia i neurochirurgia polska | Investigated pathomechanisms of Horton's cluster headache using nitroglycerin provocation and indomethacin (COX inhibitor) blockade; discusses PGI₂ as part of attack pathogenesis rather than treatment |
Singapore Market Information
Epoprostenol is not currently registered with the Health Sciences Authority (HSA) in Singapore. There are no active product licences, authorisations, or approved indications on record.
Safety Considerations
Please refer to the package insert for safety information.
Conclusion and Next Steps
Decision: Hold
Rationale: The available literature consistently positions PGI₂ (Epoprostenol) as a headache-precipitating agent rather than a therapeutic agent in trigeminal autonomic cephalalgia; the high TxGNN score reflects knowledge graph co-occurrence and is assessed as a false positive.
To proceed further, the following is needed:
- Retrieve full mechanism of action data from DrugBank (flagged as a High-severity data gap: DG002) to determine whether any downstream IP-receptor pathway could be selectively modulated for TAC benefit
- Review emerging literature on prostacyclin receptor antagonism (blocking, not activating, the IP pathway) in primary headache disorders, which would represent a conceptually different intervention
- Prioritise evaluation of the Rank 9 prediction — Respiratory Failure (Evidence Level L1, "Proceed with Guardrails") — which has multiple completed Phase 2–3 trials of inhaled Epoprostenol, including a double-blind RCT (NCT04452669) and a large multicentre RCT (NCT00159861, n = 267), representing the strongest actionable repurposing candidate for this drug within this evidence pack
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.