Fenoterol
| Evidence Level: L5 | Predicted Indications: 10 |
Table of Contents
Fenoterol: From Bronchodilator Use to Multiple System Atrophy
One-Sentence Summary
Fenoterol is a beta-2 adrenergic agonist marketed in Singapore as an inhaled or nebulised bronchodilator. The TxGNN model predicts it may be effective for multiple system atrophy, but there are 0 clinical trials and 0 publications supporting this prediction. The prediction rests on the model score alone (evidence level L5), and the pharmacology argues against it.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not stated in the Singapore licence records. Fenoterol is used as a bronchodilator, and marketed products are inhaled or nebulised forms. |
| Predicted New Indication | Multiple system atrophy |
| TxGNN Prediction Score | 99.70% |
| Evidence Level | L5 |
| Singapore Market Status | ✓ Marketed |
| Number of Registrations | 3 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism of action data is not available in the data compiled for this report. Pharmacology data show that fenoterol binds beta-1, beta-2 and beta-3 adrenoceptors. It is described as a beta-2 agonist used as a bronchodilator and, in some countries, to suppress premature labour.
A plausible link would be symptomatic modulation of autonomic dysfunction. However, beta-2 agonism has no established disease-modifying role in alpha-synucleinopathy. Vasodilation could also worsen the orthostatic hypotension that is common in multiple system atrophy. The high TxGNN score therefore looks like a network-based association rather than a therapeutic rationale.
The other top-ranked predictions have similar problems:
- Postural orthostatic tachycardia syndrome: Fenoterol is expected to aggravate this condition through tachycardia and vasodilation.
- Variably protease-sensitive prionopathy: No mechanistic link to prion misfolding can be identified.
- Open-angle and primary hereditary glaucoma: The link is theoretical and there is no fenoterol-specific evidence.
- Raynaud disease: Vasodilation is a plausible rationale, but systemic side effects limit practicality.
- Sinoatrial block and sinoatrial node disease: Chronotropic effects are theoretically helpful, but fenoterol is beta-2 selective and carries proarrhythmic risk.
The only prediction with any literature support is anaphylaxis (score 98.3%, evidence level L4). The literature there is entirely preclinical, which is why the sections below cover it.
Clinical Trial Evidence
Currently no related clinical trials registered for multiple system atrophy or any other predicted indication.
Literature Evidence
No literature is available for multiple system atrophy. The only supporting literature relates to the lower-ranked anaphylaxis prediction. All of it is animal or tissue work from 1977 to 1987, and none is human clinical data.
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 68010 | 1977 | Preclinical (rat) | Int Arch Allergy Appl Immunol | Fenoterol was the most potent of the beta-agonists tested at inhibiting IgE-mediated histamine release in passive anaphylaxis in rats. It was more potent than salbutamol and isoproterenol. |
| 6199956 | 1984 | Preclinical (guinea pig) | Agents Actions | Fenoterol attenuated antigen-induced bronchospasm and changes in tissue histamine in sensitised guinea pigs. |
| 2889607 | 1987 | Preclinical (rat) | Eur J Pharmacol | Fenoterol and sodium cromoglycate acted synergistically against anaphylactic bronchoconstriction in rats. |
| 2864902 | 1985 | Preclinical (guinea pig lung) | Arch Int Pharmacodyn Ther | Proposed a mechanism for the anti-anaphylactic effect of beta-agonists, involving thromboxane A2 release. |
| 6203772 | 1984 | Preclinical (human and guinea pig airway tissue) | Eur J Respir Dis Suppl | Characterised the beta-adrenoceptor subtypes mediating airway relaxation and inhibition of antigen-induced histamine release. |
| 98295 | 1978 | Preclinical (rat) | Chest | Compared the effects of fenoterol on passive cutaneous anaphylaxis and the histamine skin test in rats. |
Singapore Market Information
The licence records do not list approved indication text. The products are inhaled or nebulised forms.
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| SIN07913P | DUOVENT UDVS NEBULISER SOLUTION | Solution | Not stated |
| SIN11739P | BERODUAL N METERED DOSE INHALER | Aerosol, spray | Not stated |
| SIN02664P | BERODUAL SOLUTION | Solution | Not stated |
Safety Considerations
- Drug Interactions: No specific drug-drug interactions were identified. The available data only show fenoterol binding to beta-1, beta-2 and beta-3 adrenoceptors (ADRB1, ADRB2, ADRB3).
- Predicted-indication concerns: Beta-2 agonism can cause tachycardia, tremor and vasodilation. These effects could worsen orthostatic hypotension (relevant to multiple system atrophy) and postural orthostatic tachycardia syndrome. They also carry proarrhythmic risk in sinoatrial disease.
Please refer to the package insert for warnings and contraindications. These were not available in the data compiled for this report.
Conclusion and Next Steps
Decision: Hold
Rationale: The prediction for multiple system atrophy is supported only by a model score, with no trials or literature. Fenoterol's vasodilatory and chronotropic effects may also be harmful in autonomic disorders. Among the predicted indications, only anaphylaxis has even preclinical support, and epinephrine remains its standard of care.
To proceed, the following is needed:
- Package insert warnings and contraindications from the Health Sciences Authority (HSA), which is a blocking gap for safety screening
- Detailed mechanism of action data
- Any human evidence for multiple system atrophy. Without it, the prediction should not progress.
- If the anaphylaxis direction is of interest, a research question on fenoterol as an adjunct for bronchospasm, starting with a review of human data
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.