Bosentan
| Evidence Level: L4 | Predicted Indications: 8 |
Table of Contents
Bosentan: From Pulmonary Arterial Hypertension to Rheumatoid Arthritis
One-Sentence Summary
Bosentan was originally used to treat pulmonary arterial hypertension, including forms linked to systemic sclerosis (scleroderma). The TxGNN model predicts it may be effective for Rheumatoid Arthritis, but the support is early-stage: 0 clinical trials are registered, and the available literature consists mainly of animal studies and reviews.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Pulmonary arterial hypertension (also systemic sclerosis / scleroderma) |
| Predicted New Indication | Rheumatoid arthritis |
| TxGNN Prediction Score | 0.9980 |
| Evidence Level | L4 |
| Canada Market Status | Marketed (marketed DINs: 6 of 8; dormant: 2) |
| Number of DINs | 8 (marketed: 6) |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available in the data compiled for this report. The literature describes bosentan as a dual endothelin receptor (ETA/ETB) antagonist. Its efficacy in pulmonary arterial hypertension is established, and mechanistically it may be applicable to inflammatory joint disease.
Endothelin-1 contributes to synovial inflammation, vascular dysfunction and the release of inflammatory mediators such as TNF-alpha and LTB4. Endothelin-1 levels are reported to be raised in the blood and synovial membrane of rheumatoid arthritis patients. In a mouse model of collagen-induced arthritis, bosentan reduced disease, apparently through a TNF-alpha-dependent mechanism. Blocking endothelin receptors also modulated inflammation in a zymosan-induced arthritis model.
These findings come only from animal models. No human data show that bosentan treats rheumatoid arthritis. Most of the human literature retrieved concerns pulmonary hypertension associated with connective tissue disease, which is the drug’s existing indication area rather than arthritis treatment. The prediction is therefore best viewed as a research hypothesis.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 22249931 | 2012 | Preclinical (mouse) | Inflamm Res | Bosentan ameliorated collagen-induced arthritis; TNF-α was involved in inducing endothelin system genes |
| 18515326 | 2008 | Preclinical (mouse) | J Leukoc Biol | Endothelin receptor blockade modulated neutrophil accumulation and edema in zymosan-induced arthritis via LTB4, TNF-α and CXCL-1 |
| 16766656 | 2006 | Preclinical (mouse, not bosentan-specific) | Proc Natl Acad Sci USA | IL-15-induced joint pain sensitization was inhibited by a dual ETA/ETB antagonist |
| 19969421 | 2010 | Preclinical (mouse, not bosentan-specific) | Pain | IL-17 mediates joint pain in antigen-induced arthritis; supports the cytokine and endothelin context in RA |
| 24268012 | 2014 | Review | Rheum Dis Clin North Am | PAH related to connective tissue disease carries high morbidity and mortality; treatment options have improved survival |
| 16218473 | 2005 | Review | Lupus | PAH occurs in connective tissue diseases, less often in rheumatoid arthritis |
| 19487226 | 2009 | Review | Rheumatology (Oxford) | Vascular disease and PAH in lupus and Sjögren’s syndrome; PAH has a major effect on prognosis |
| 21165350 | 2010 | Review | Can Respir J | Treating pulmonary hypertension in connective tissue disease with or without interstitial lung disease; effects of targeted therapy in combined disease are poorly characterized |
| 20054770 | 2009 | Case report | Kardiol Pol | Girl with Eisenmenger syndrome treated with bosentan who was later diagnosed with juvenile rheumatoid arthritis; the two conditions coexisted and no arthritis benefit was shown |
| 19851110 | 2010 | Review | Curr Opin Rheumatol | Overview of rheumatic skin diseases and their therapies; not specific to bosentan |
Canada Market Information
Eight valid single-ingredient authorizations are listed. Dosage form and approved-indication text were not available in the data compiled for this report. The five main ones are:
| DIN | Product Name |
|---|---|
| 02244981 | TRACLEER |
| 02244982 | TRACLEER |
| 02483130 | TARO-BOSENTAN |
| 02383020 | PMS-BOSENTAN |
| 02467992 | NAT-BOSENTAN |
Safety Considerations
Label-based warnings and contraindications were not available, so please refer to the package insert for authoritative safety information. The following supporting information was compiled from other sources.
- Contraindication signals (knowledge graph, not label text): liver failure, liver disease, drug-induced liver injury, hyperbilirubinemia (including hereditary forms and Gilbert syndrome), gallbladder disease, thrombocytopenia, anemia (including macrocytic anemia), congestive heart failure, pulmonary edema, and pulmonary veno-occlusive disease.
- Drug interactions: 100 interactions are recorded. The main ones shown are all rated Moderate:
- Corticosteroids: hydrocortisone, dexamethasone, betamethasone, triamcinolone
- Antidiabetic agents: pioglitazone, canagliflozin, dapagliflozin, empagliflozin, ertugliflozin, chlorpropamide, acetohexamide
- Other: aprepitant, metronidazole, cimetidine, cisapride, clarithromycin, clotrimazole, dronabinol, eliglustat, eluxadoline
Conclusion and Next Steps
Decision: Hold
Rationale: Support for rheumatoid arthritis is limited to mouse-model studies, with no registered clinical trials and no human efficacy data (Evidence Level L4). The high TxGNN score alone is not enough to justify moving forward.
Among the other predictions, limited systemic sclerosis has the strongest support (a 2023 systematic review on digital ulcers and an in vitro study). That indication largely overlaps the drug’s existing use, so it is more an extension of the current label than true repurposing.
To proceed, the following is needed:
- Mechanism of action data confirmed from DrugBank
- Package insert warnings and contraindications from Health Canada, particularly hepatotoxicity and pregnancy-related risks
- Human proof-of-concept evidence in rheumatoid arthritis, such as a pilot study or well-designed clinical trial
- Assessment of how the existing safety profile (liver monitoring, drug interactions) fits the rheumatoid arthritis population, which often takes corticosteroids and other interacting drugs
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.