Ethambutol
| Evidence Level: L5 | Predicted Indications: 5 |
Table of Contents
Ethambutol: Epiglottitis
One-Sentence Summary
Ethambutol is an antimycobacterial drug originally used to treat pulmonary tuberculosis. The TxGNN model predicts it may be effective for epiglottitis, but there are 0 clinical trials and only 1 publication (a case series on laryngeal tuberculosis) behind this prediction, so it is best read as a model-driven signal and not a true new indication.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not recorded in the local data |
| Predicted New Indication | Epiglottitis |
| TxGNN Prediction Score | 0.9990 |
| Evidence Level | L5 |
| India Market Status | Listed in a compiled Indian medicine price dataset (at least 20) – CDSCO approval status is not included in this data |
| Number of Listed Products | at least 20 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available in the data compiled for this report. Based on known information, ethambutol is an antimycobacterial agent that inhibits arabinosyl transferases involved in building the mycobacterial cell wall. Its efficacy in tuberculosis is well established as part of standard multidrug regimens.
The only linked literature is a case series of laryngeal tuberculosis, in which the epiglottis was one of the affected sites and ethambutol was part of the treatment. The link is therefore indirect and driven by tuberculosis.
The high TxGNN score most likely reflects network proximity to upper airway tuberculosis. At most, this would be an extension of the existing tuberculosis indication to a different anatomical site, not true repurposing.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 2806495 | 1989 | Case series | Eur Respir J | 41 cases of laryngeal tuberculosis (1975–1985). The epiglottis was among the sites affected. Patients were usually treated with isoniazid, rifampicin and ethambutol. |
India Market Information
Ethambutol is marketed in India as single-ingredient oral tablets. The data compiled for this report contain no approved indication text for these registrations. The main registrations are listed below (5 of 20).
| Authorization Number | Product Name | Dosage Form | Manufacturer |
|---|---|---|---|
| 209270 | Sunibutol 800mg Tablet | Strip of 10 tablets | Sunij Pharma Pvt Ltd |
| 212836 | Sunibutol 600mg Tablet | Strip of 10 tablets | Sunij Pharma Pvt Ltd |
| 82483 | EBL 800mg Tablet | Strip of 10 tablets | Acron Pharmaceuticals |
| 35618 | Combutol 200 Tablet | Strip of 10 tablets | Lupin Ltd |
| 56636 | CAVIBUTOL 200MG TABLET | Strip of 10 tablets | Wockhardt Ltd |
Safety Considerations
- Contraindication-related conditions (from the drug–disease knowledge graph, not label text): kidney disease, pyoureter, gout, diabetic retinopathy, diabetic cataract, optic neuritis.
- Drug Interactions: 112 interacting drugs were identified. Those rated Moderate include metronidazole, picosulfuric acid, naltrexone, rosuvastatin, simvastatin, tinidazole and aluminum hydroxide. Others, such as proton pump inhibitors (omeprazole, pantoprazole, lansoprazole), corticosteroids (prednisone, prednisolone, hydrocortisone), vancomycin, morphine and sulfasalazine, have an unclassified severity level.
Please refer to the package insert for label warnings and contraindications.
Conclusion and Next Steps
Decision: Hold
Rationale: No clinical trials exist, and the single supporting publication is an old case series of laryngeal tuberculosis. It supports using ethambutol for tuberculosis at a new site, not for epiglottitis in general. There is no mechanistic basis for activity against typical epiglottitis pathogens.
To proceed, the following is needed:
- Package insert warnings and contraindications, which are currently missing and block safety screening
- Detailed mechanism of action data
- Confirmation that the target population is limited to tuberculous (mycobacterial) epiglottitis or laryngitis, with supporting clinical data
- Any prospective clinical evidence for this site of disease
- A review of ocular toxicity (optic neuritis) and renal function monitoring for any new use
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.