Tetracycline
| Evidence Level: L4 | Predicted Indications: 4 |
Table of Contents
Tetracycline: From Antibiotic Therapy to Punctate Epithelial Keratoconjunctivitis
One-Sentence Summary
Tetracycline is a long-established antibiotic, used for bacterial infections including chlamydial eye infections such as trachoma and inclusion conjunctivitis. The TxGNN model predicts it may be effective for punctate epithelial keratoconjunctivitis, but the support is thin: 0 clinical trials and 1 publication, a small case series.
Quick Overview
| Item | Content |
|---|---|
| Predicted New Indication | Punctate epithelial keratoconjunctivitis |
| TxGNN Prediction Score | 99.58% |
| Evidence Level | L4 |
| US Market Status | ✓ Marketed |
| Number of NDAs | 20 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available. Based on known information, tetracycline is part of the tetracycline antibiotic class. Its efficacy in chlamydial eye infection (trachoma and inclusion conjunctivitis) is established. Mechanistically, it may be applicable to punctate keratoconjunctivitis through anti-inflammatory or matrix metalloproteinase (MMP)-inhibiting effects, a property described for tetracycline-class drugs.
The link to the original use is indirect. Punctate keratitis can persist or recur after a chlamydial infection has cleared, so an antibacterial effect alone would not explain any benefit. The score is very high (99.58%), but there is no mechanistic or clinical evidence specific to this indication. The score should be read as a model signal, not confirmation.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 1424659 | 1992 | Case series (2 patients) | Cornea | Two patients with chlamydial follicular conjunctivitis were treated with oral tetracycline or doxycycline, and the follicles resolved. Both then developed recurrent, bilateral punctate epithelial keratitis. The report describes keratitis persisting after antibiotic treatment, not a benefit from it. |
US Market Information
Approved indication text is not listed in the source data for these products.
| Authorization Number | Product Name | Dosage Form |
|---|---|---|
| ANDA210674 | Tetracycline Hydrochloride | Capsule |
| ANDA061147 | Tetracycline Hydrochloride | Tablet, film coated |
| M004 | Vitastem-tetracycline hydrochloride | Spray |
| ANDA061837 | Tetracycline Hydrochloride | Capsule |
| ANDA210662 | Tetracycline Hydrochloride | Capsule |
Safety Considerations
Please refer to the package insert for safety information.
Conclusion and Next Steps
Decision: Hold
Rationale: The only evidence is a two-patient case series that reports keratitis persisting after tetracycline-class treatment. There are no clinical trials and no indication-specific mechanistic data, so the high model score has no supporting evidence behind it.
To proceed, the following is needed:
- Package insert safety information (warnings and contraindications), which is currently missing and blocks safety screening
- Mechanism of action data
- Ocular-specific clinical or preclinical evidence, including which route would be needed (topical ocular versus oral)
- A separate look at other predicted indications for this drug. Chronic rhinosinusitis (score 99.15%) has a completed Phase 3 trial and several RCTs and meta-analyses, but all of them test doxycycline rather than tetracycline, so any extrapolation is class-level only.
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.