Cefaclor
| Evidence Level: L3 | Predicted Indications: 10 |
Table of Contents
Cefaclor: From Bacterial Infections to Gonococcal Urethritis
One-Sentence Summary
Cefaclor is an oral cephalosporin antibiotic originally used for respiratory, urinary tract, and other bacterial infections. The TxGNN model's top-ranked predictions are mostly unrelated to infection, and the most clinically coherent one is Gonococcal Urethritis, supported by 6 publications (1979–1997) and no registered clinical trials. The top two predictions by score (hyperamylasemia and polyclonal hyperviscosity syndrome) have no supporting evidence or plausible mechanism, so this report focuses on the best-supported candidate.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Urinary tract infection, tonsillitis, pharyngitis, pneumonia, streptococcal and staphylococcal infections (from the knowledge graph; the Singapore licence records contain no indication text) |
| Predicted New Indication | Gonococcal urethritis (best-supported candidate; the highest-scoring prediction is hyperamylasemia, which has no evidence) |
| TxGNN Prediction Score | 97.48% (gonococcal urethritis); for reference, hyperamylasemia 97.70% |
| Evidence Level | L3 |
| Singapore Market Status | ✓ Marketed |
| Number of Registrations | 2 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism of action data is not available in the data compiled for this report. Based on known information, cefaclor is a beta-lactam cephalosporin that inhibits bacterial cell wall synthesis. Its efficacy in common bacterial infections is established, and mechanistically it may be applicable to infections caused by susceptible organisms such as Neisseria gonorrhoeae.
Gonococcal urethritis is a bacterial infection, so it sits close to cefaclor's existing antibacterial uses. Early studies from the late 1970s to 1990s reported clinical use in men with uncomplicated gonococcal urethritis, including single-dose oral regimens. However, this is arguably an extension of existing antibacterial use rather than true repurposing. Current guidelines rely on ceftriaxone-based therapy because of gonococcal resistance, so cefaclor is unlikely to be clinically relevant today.
The other top-ranked predictions are weak:
- Hyperamylasemia, polyclonal hyperviscosity syndrome, congenital analbuminemia, blood group incompatibility, premalignant hematological disease, monoclonal gammopathy: no plausible mechanistic link. The scores appear to be graph-based artefacts. For blood group incompatibility, cephalosporins are associated with immune-mediated haemolysis, so safety concerns would outweigh any speculative benefit.
- Ureaplasma urethritis: Ureaplasma lacks a cell wall, so beta-lactams are expected to be intrinsically ineffective.
- Uterine inflammatory disease and xanthogranulomatous pyelonephritis: some indirect rationale where the cause is bacterial, but no evidence was found, and cefaclor is not a standard agent for these conditions.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
The evidence below is for gonococcal urethritis. Study designs are not confirmed and were judged largely from titles and abstracts.
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 9582471 | 1997 | Clinical study | Genitourinary Medicine | Reassessed in vivo and in vitro efficacy of cefaclor as an alternative to third-generation cephalosporins in the developing world |
| 6225482 | 1983 | Randomised comparative study | British Journal of Venereal Diseases | 400 men; cure rates of 98.9% (spectinomycin), 70.8% (cefamandole), 95.8% (cefaclor 3 g + probenecid) and 89.6% (cefaclor 3 g alone) |
| 116373 | 1979 | Randomised trial | Sexually Transmitted Diseases | Cefaclor at 2, 3 and 4 g, with or without probenecid, given daily for 3 days in uncomplicated gonococcal urethritis in men |
| 121455 | 1979 | Clinical study | Postgraduate Medical Journal | 40 men with uncomplicated gonococcal urethritis treated with a 1 g loading dose of cefaclor; good in vitro activity against N. gonorrhoeae |
| 6400040 | 1984 | Clinical study | Medical Journal of Malaysia | Single-dose oral cefaclor in men with uncomplicated gonococcal urethritis (no abstract available) |
| 2673664 | 1989 | Clinical experience report | Current Medical Research and Opinion | Primarily about cefetamet pivoxil, with cefaclor and cefadroxil as comparators; indirect relevance |
Singapore Market Information
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| SIN09294P | CLEANCEF CAPSULE 250 mg | Capsule | Not stated in the available records |
| SIN11733P | SOFICLOR FOR ORAL SUSPENSION 125 mg/5 ml | Granule, for suspension | Not stated in the available records |
Safety Considerations
- Contraindications (knowledge graph, not label text): Clostridium difficile colitis and perinatal necrotizing enterocolitis.
- Drug Interactions: 69 interactions were identified. Moderate-level ones include:
- Balsalazide
- Picosulfuric acid
- Magnesium hydroxide
- Aluminium hydroxide
Other interactions listed, with severity not classified, include calcitriol, pantoprazole, mesalazine, doxycycline, morphine, metformin, omeprazole, lansoprazole, cimetidine, simvastatin, and several corticosteroids.
Please refer to the package insert for the full safety information, as label warnings and contraindications were not available.
Conclusion and Next Steps
Decision: Hold
Rationale: Only gonococcal urethritis has any supporting evidence, and it is limited to small, older studies of uncertain design. Cefaclor is no longer a guideline-recommended option because of gonococcal resistance. All other predictions have no trials, no literature, and in several cases no plausible mechanism, so the model score alone does not justify moving forward.
To proceed, the following is needed:
- The Singapore package insert warnings and contraindications (a blocking gap for safety screening)
- Detailed mechanism of action data
- Current gonococcal resistance data, and a comparison with guideline-recommended therapy
- Confirmation of the design and quality of the published gonococcal urethritis studies
- Approved indication text for the two Singapore licences
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.