Tobramycin
| 證據等級: L5 | 預測適應症: 10 個 |
目錄
Tobramycin: From Gram-Negative Bacterial Infections to Exposure Keratitis
One-Sentence Summary
Tobramycin is an aminoglycoside antibiotic historically used against Pseudomonas aeruginosa and other gram-negative bacterial infections. The TxGNN model predicts it may be relevant for Exposure Keratitis, with 2 clinical trials and 7 publications currently identified, though none directly test tobramycin as primary therapy for this specific condition.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not documented in this evidence pack — no U.S. license records were retrieved; based on drug class, tobramycin is used against gram-negative bacterial infections (e.g., Pseudomonas aeruginosa) |
| Predicted New Indication | Exposure Keratitis |
| TxGNN Prediction Score | 99.93% |
| Evidence Level | L4 |
| US Market Status | Not Marketed |
| Number of NDAs | 0 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism-of-action data is not available in this evidence pack (flagged as a High-severity data gap, DG002). Based on the repurposing rationale supplied, tobramycin is an aminoglycoside antibiotic with strong activity against Pseudomonas aeruginosa and other gram-negative organisms, an antibacterial spectrum that has long supported its use in ophthalmic and otic infections.
Exposure keratitis, however, is primarily a non-infectious, mechanical condition caused by incomplete eyelid closure (lagophthalmos) leading to corneal drying and epithelial breakdown. The evidence pack’s own mechanistic assessment notes this distinction directly: tobramycin could theoretically play a role in preventing or treating secondary bacterial infection of an already-compromised corneal surface, but it does not address the underlying etiology of exposure keratitis itself. This makes the pharmacological link plausible but adjunctive rather than primary — consistent with the “Research Question” classification assigned to this candidate in the source scoring.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT05313828 | N/A | Unknown | 40 | Study of various treatment modalities for dendritic viral (herpetic) corneal ulcer; tobramycin not a primary intervention, and viral etiology is not a typical antibiotic target (relevance grade C) |
| NCT06200727 | N/A | Unknown | 170 | Evaluates platelet-rich fibrin (PRF) membrane across four ophthalmic conditions including corneal ulcer; no direct tobramycin arm (relevance grade C) |
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 34987857 | 2021 | Case Report | Oxford Medical Case Reports | Multidrug-resistant Shewanella algae keratitis in a bedridden patient unable to close eyes voluntarily — an exposure-related infectious keratitis scenario |
| 11581057 | 2001 | Case Report | Ophthalmology | Bacillus cereus keratitis associated with contact lens wear |
| 12861116 | 2003 | Case Report | Eye & Contact Lens | Bilateral MRSA keratitis following photorefractive keratectomy |
| 2707046 | 1989 | In Vitro | Current Eye Research | Compared corneal epithelial cytotoxicity of aminoglycosides (including tobramycin) in a rabbit model |
| 17228760 | 2006 | In Vitro/Lab | Nippon Ganka Gakkai Zasshi | Compared MIC and postantibiotic effect of antibiotic eyedrops (incl. tobramycin) against infectious keratitis isolates in Japan |
| 33847093 | 2021 | Pending classification | Polish Journal of Veterinary Sciences | Feline ocular toxoplasmosis case series; no direct tobramycin or human relevance |
| 14574976 | 2003 | Pending classification | Yan Ke Xue Bao / Eye Science | Case report of corneal dellen in Graves ophthalmopathy; no direct tobramycin data |
US Market Information
Tobramycin currently has no license records in the reviewed evidence pack (market_status: 未上市 / Not Marketed, total_licenses: 0). No NDA-level product information is available for this jurisdiction at this time.
Safety Considerations
Please refer to the package insert for safety information. (Key warnings, contraindications, and drug-drug interaction data were not available in this evidence pack — flagged as a Blocking-severity data gap, DG001.)
Conclusion and Next Steps
Decision: Hold
Rationale: The mechanistic link is indirect — exposure keratitis is fundamentally a mechanical/non-infectious condition, and available clinical trials (grade C relevance) and literature (predominantly case reports of secondary infection in exposed corneas) do not directly test tobramycin as a primary therapy for this indication. Evidence level is L4 (mechanistic/preclinical), insufficient to support active development at this stage.
To proceed, the following is needed:
- Tobramycin mechanism-of-action data (DG002) to formally assess mechanistic relevance
- FDA/TFDA label warnings and contraindications (DG001) before any safety pre-screening (S1) can proceed
- Direct clinical evidence (e.g., RCTs) evaluating tobramycin specifically for prevention/treatment of secondary infection in exposure keratitis, rather than general keratitis or unrelated conditions
- Route-of-administration and formulation compatibility data (ophthalmic route) for this specific indication
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.