Valproic Acid
| Evidence Level: L5 | Predicted Indications: 10 |
Table of Contents
Valproic Acid: From Epilepsy to Trigeminal Nerve Neoplasm
One-Sentence Summary
Valproic acid is an established antiseizure and mood-stabilising drug, originally used for epilepsy and manic episodes of bipolar disorder. The TxGNN model predicts it may be effective for trigeminal nerve neoplasm, but there are currently 0 clinical trials and only 1 publication, and that publication is not about this tumour type, so the prediction rests almost entirely on the model's graph-based score.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Epilepsy, manic bipolar affective disorder, absence epilepsy (from the TxGNN knowledge graph; the Singapore licence records contain no indication text) |
| Predicted New Indication | Trigeminal nerve neoplasm |
| TxGNN Prediction Score | 99.97% |
| Evidence Level | L5 |
| Singapore Market Status | ✓ Marketed |
| Number of Registrations | 11 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism of action data is not currently available for this drug. Based on known information, valproic acid is a broad-spectrum antiseizure agent whose efficacy in epilepsy is well established. A speculative rationale is that it acts as a histone deacetylase (HDAC) inhibitor, which could give it antineoplastic activity. This has not been tested for this tumour type.
The relationship between the original and predicted indications is weak. Epilepsy is a functional neurological disorder, whereas trigeminal nerve neoplasm is a tumour of a cranial nerve. The high TxGNN score most likely reflects the drug's many neurological associations in the knowledge graph rather than tumour-specific biology. The only publication found concerns Sturge-Weber syndrome, a neurocutaneous disorder with seizures, and does not support valproic acid for this tumour.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 9157801 | 1997 | Case series | Anales espanoles de pediatria | Review of 14 Sturge-Weber syndrome cases for clinical features, course and treatment response. It does not address trigeminal nerve neoplasm, so it offers no direct support. |
Singapore Market Information
There are 11 valid single-ingredient registrations. The licence records do not include approved indication text. The five main authorisations are:
| Authorization Number | Product Name | Dosage Form |
|---|---|---|
| SIN05690P | Epilim 200 Tablet 200 mg | Enteric coated tablet |
| SIN08537P | Epilim Chrono Tablet 200 mg | Film-coated tablet |
| SIN05434P | Epilim Syrup 200 mg/5 ml | Syrup |
| SIN05215P | Epilim 400 mg Powder for injection / infusion | Powder for solution for injection |
| SIN16642P | Valproate-AFT Solution for Infusion/Injection 100 mg/ml | Solution for injection |
Safety Considerations
- Contraindications suggested by the knowledge graph (not taken from label text): anxiety disorder, neurotic disorder, dysthymic disorder, carbamoyl phosphate synthetase I deficiency, inherited porphyria and other porphyrias, kidney disease, pyoureter, hyperargininemia, haematologic disease, pancreatitis, citrullinemia, cognitive disorder, liver disease, gallbladder disease, thrombocytopenia.
- Drug interactions: 100 interactions were identified, and the first 20 are summarised here.
- Major: glycerol phenylbutyrate.
- Moderate: bupropion, morphine (including liposomal), acetylsalicylic acid, clarithromycin, difenoxin, diphenoxylate, activated charcoal, dronabinol, metoclopramide, nabilone.
- Minor: cimetidine, esomeprazole, and several antacids (magnesium oxide, aluminium hydroxide, calcium carbonate, magaldrate, magnesium carbonate, magnesium hydroxide).
Please refer to the package insert for warnings and formal contraindications, as label-based safety text is not available.
Conclusion and Next Steps
Decision: Hold
Rationale: The prediction has no supporting clinical trials and no relevant literature, so it is a model output only (L5). The single publication retrieved concerns a different condition.
To proceed, the following is needed:
- Tumour-specific preclinical evidence, such as HDAC-inhibition studies in relevant cranial nerve tumour models
- Mechanism of action data
- Package insert warnings and contraindications from the Singapore regulator
- A review of whether other predicted indications for this drug, such as visual epilepsy (L3), have a stronger evidence base and should be prioritised instead
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.