Rifampicin
| Evidence Level: L4 | Predicted Indications: 10 |
Table of Contents
Rifampicin: From Pulmonary Tuberculosis to Conjunctivitis
One-Sentence Summary
Rifampicin is an antibiotic originally used to treat pulmonary tuberculosis. The TxGNN model predicts it may be effective for conjunctivitis. No clinical trials are registered for this indication and 20 publications were retrieved, mostly susceptibility surveys, case reports and older reviews, so the evidence remains limited.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Pulmonary tuberculosis |
| Predicted New Indication | Conjunctivitis |
| TxGNN Prediction Score | 0.9995 |
| Evidence Level | L4 |
| Canada Market Status | Marketed (marketed DINs: 2 of 2) |
| Number of DINs | 2 (marketed: 2) |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available. Based on known information, rifampicin is a broad-spectrum antibacterial agent that inhibits bacterial RNA polymerase. Its efficacy in pulmonary tuberculosis is well established, and mechanistically it may be applicable to bacterial conjunctivitis.
The literature indicates activity against Gram-positive bacteria (such as Staphylococcus), Chlamydia and some other ocular pathogens, which makes antibacterial use in infectious conjunctivitis plausible. Topical rifampicin has been studied mainly in trachoma and chlamydial eye infection. A 1975 controlled trial in Tunisia compared 1% rifampicin ointment, 1% tetracycline ointment and boric acid ointment in trachoma. A 1977 open trial in London (63 patients) found that a 6 to 7 week course of 1% rifampicin eye ointment gave about 90% clinical and microbiological cure in chlamydial eye infection, whereas 3 weeks was not enough.
This evidence is old and mostly indirect. No controlled trial of rifampicin in common conjunctivitis was found. Many cases are viral or are well treated by established first-line agents, so the unmet need is unclear.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 1096630 | 1975 | Controlled clinical study | Am J Ophthalmol | 1% rifampicin ointment vs 1% tetracycline ointment vs boric acid ointment in endemic trachoma in Tunisian schoolchildren (about 230 patients) |
| 322700 | 1977 | Open trial | Br J Ophthalmol | 1% rifampicin vs chloramphenicol eye ointment in 63 patients with chlamydial eye infection; 6 to 7 weeks gave about 90% cure |
| 5005929 | 1971 | Review | Ann Ophthalmol | Overview of rifampicin (no abstract available) |
| 33457332 | 2020 | Cross-sectional susceptibility study | Adv Biomed Res | Bacterial causes and antibiotic susceptibility of conjunctivitis isolates in Kashan, Iran |
| 8363150 | 1993 | Cohort/microbiology study | An Esp Pediatr | Microbiology and antibiotic sensitivity in 50 cases of neonatal conjunctivitis |
| 21191558 | 2010 | In vitro susceptibility study | Rev Esp Quimioter | Antibiotic susceptibility of Corynebacterium macginleyi strains causing conjunctivitis |
| 30347565 | 2018 | Genotyping/susceptibility study | Zhonghua Yan Ke Za Zhi | Genetic typing and susceptibility of S. aureus from keratitis or conjunctivitis |
| 3191080 | 1988 | Case report | Br J Ophthalmol | Marginal corneal abscess in adult chlamydial ophthalmia |
| 39336466 | 2024 | Case report | Medicina (Kaunas) | Parinaud oculoglandular syndrome with Bartonella DNA detected in cornea and conjunctiva |
| 1247775 | 1976 | Report | Br Med J | Ocular toxicity due to rifampicin (a safety signal in the eye) |
Canada Market Information
| DIN | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 00343617 | ROFACT | Not specified | Not specified |
| 00393444 | ROFACT | Not specified | Not specified |
Safety Considerations
- Contraindications suggested by the knowledge graph (these come from knowledge-graph relationships, not from label text): liver failure, acute liver failure, liver disease, hepatitis, gallbladder disease, porphyria (including inherited porphyria and porphyrin metabolism disease), thrombocytopenia, neutropenia, agranulocytosis, pancytopenia, anaemia (including macrocytic and aplastic anaemia), diabetes mellitus, diabetic ketoacidosis, gout, peripheral neuropathy and other peripheral nervous system disease, substance abuse/dependence, slow acetylator status, anxiety and neurotic disorders, dysthymic disorder, and non-infectious meningitis.
- Drug Interactions: The interaction screen returned 100 interacting drugs; the 20 listed in the data compiled for this report were all of Moderate severity. They include omeprazole, rabeprazole, doxycycline, clarithromycin, metronidazole, metformin, pioglitazone, canagliflozin, chlorpropamide, bupropion, aprepitant, morphine, dexamethasone, hydrocortisone, betamethasone, triamcinolone, cholecalciferol, calcifediol, calcitriol and picosulfuric acid. Rifampicin is a strong enzyme inducer, so it can lower exposure to many co-administered drugs.
- Ocular safety: Early reports (1976) describe ocular toxicity with rifampicin, which should be considered if topical or ocular use is explored.
Package insert warnings and contraindications from Health Canada were not available, so please refer to the package insert for full safety information.
Conclusion and Next Steps
Decision: Hold
Rationale: Rifampicin’s antibacterial activity makes a role in infectious conjunctivitis plausible, and older studies in trachoma and chlamydial eye infection used topical rifampicin. However, there are no registered trials, no modern controlled evidence in conjunctivitis, and no clear unmet need over established treatments. The evidence level is L4.
To proceed, the following is needed:
- Health Canada package insert warnings and contraindications, which are required for safety screening
- Detailed mechanism of action data
- A topical or ophthalmic formulation and route-compatibility assessment, because the marketed ROFACT products have no listed dosage form or indication
- Defining the target pathogen subgroup (for example chlamydial or trachoma-type conjunctivitis) and confirming the unmet need against current first-line therapy
- Controlled efficacy data in the chosen subgroup, plus a review of ocular tolerability
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.