Chlortetracycline
| Evidence Level: L5 | Predicted Indications: 10 |
Table of Contents
Chlortetracycline: From Trachoma to Postinfectious Vasculitis
One-Sentence Summary
Chlortetracycline is a tetracycline-class antibiotic, originally used for infections such as trachoma, ornithosis and ophthalmia neonatorum. The TxGNN model predicts it may be effective for postinfectious vasculitis, but there are currently 0 clinical trials and 0 publications supporting this prediction. This is a model-only prediction.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Trachoma, ornithosis, ophthalmia neonatorum (from the knowledge graph; the Singapore licence lists no approved indication text) |
| Predicted New Indication | Postinfectious vasculitis |
| TxGNN Prediction Score | 99.82% |
| Evidence Level | L5 |
| Singapore Market Status | ✓ Marketed |
| Number of Registrations | 1 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available. Based on known information, chlortetracycline is a tetracycline-class antibiotic. Its efficacy in bacterial eye infections is established, and mechanistically it may be applicable to postinfectious vasculitis.
A plausible but unverified link is the anti-inflammatory activity seen in this class, such as inhibition of matrix metalloproteinases (MMPs) and modulation of neutrophil function. Postinfectious vasculitis is an immune-mediated inflammatory condition that follows an infection, so such effects could be relevant in principle. The data compiled for this report contain no trials or publications to confirm this.
Other predictions in the top 10 (all L5, all Hold, none with supporting trials):
| Rank | Predicted Indication | Score | Comment |
|---|---|---|---|
| 2 | Post-bacterial disorder | 99.82% | Broad, non-specific category |
| 3 | Post-infectious syndrome | 99.81% | Generic category, no defined pathophysiology |
| 4 | Infective urethral stricture | 99.81% | Strictures are fibrotic and usually need mechanical or surgical management |
| 5 | Otitis externa | 99.79% | Antibacterial rationale plausible, but established topical therapies exist |
| 6 | Chagas cardiomyopathy | 99.78% | Antiparasitic or anti-inflammatory effect speculative |
| 7 | Infection-related haemolytic uraemic syndrome | 99.78% | Antibiotics may increase toxin release in toxin-mediated HUS, a safety concern |
| 8 | Parasitic eyelid infestation | 99.04% | One publication found, but it concerns tea tree oil, not chlortetracycline |
| 9 | Ulcerative blepharitis | 99.00% | Loosely related to the original ocular uses |
| 10 | Blepharoconjunctivitis | 98.91% | Loosely related to the original ocular uses |
Literature Evidence
For the top-ranked prediction (postinfectious vasculitis), currently no related literature is available.
The only publication found across the top 10 predictions relates to rank 8 (parasitic eyelid infestation):
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 21955627 | 2012 | Clinical study (design not confirmed) | Cornea | Tested 5% tea tree oil ointment for ocular itching associated with ocular demodicosis. It does not involve chlortetracycline and is not direct evidence for this drug. |
Singapore Market Information
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| SIN04539P | CHLORTRALIM OPHTHALMIC OINTMENT 1% | Ointment | Not stated in the available data |
Only one valid single-ingredient registration exists, and it is an ophthalmic ointment. This matters for systemic conditions such as vasculitis, Chagas cardiomyopathy or HUS, because no systemic formulation is registered in Singapore according to the data compiled. Route compatibility has not been assessed.
Safety Considerations
Please refer to the package insert for safety information.
No drug interaction records were found, and no contraindications from the knowledge graph were listed.
Conclusion and Next Steps
Decision: Hold
Rationale: The prediction score is very high (99.82%), but it is based on the model alone. No clinical trials or publications support any of the top 10 predicted indications for chlortetracycline, so the evidence level is L5. The only registered product is an ophthalmic ointment, and the package insert safety information has not been obtained.
To proceed, the following is needed:
- Package insert warnings and contraindications from HSA (currently a blocking gap for safety screening)
- Mechanism of action data from DrugBank
- A literature and trial search specific to chlortetracycline or tetracyclines in postinfectious vasculitis
- An assessment of route compatibility, since the registered product is topical and the predicted indication is likely systemic
- Consideration of the ocular predictions (ulcerative blepharitis, blepharoconjunctivitis, otitis externa), which fit the existing ophthalmic ointment better, although they also lack direct evidence
- Caution with the infection-related HUS prediction, because antibiotics may worsen toxin-mediated disease
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.