Epinephrine
| Evidence Level: L1 | Predicted Indications: 10 |
Table of Contents
Epinephrine: From Asthma and Anaphylaxis to Obstructive Lung Disease
One-Sentence Summary
Epinephrine is a non-selective adrenergic agonist, originally used for asthma, anaphylaxis, bronchitis, emphysema, hypotensive disorders and open-angle glaucoma. The TxGNN model predicts it may be effective for obstructive lung disease, with 16 clinical trials and 20 publications compiled for this prediction. Much of this prediction rediscovers an existing use, and the strongest evidence is in asthma (Phase 3 trials of an inhaled epinephrine formulation).
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Asthma, anaphylaxis, bronchitis, pulmonary emphysema, hypotensive disorder, open-angle glaucoma (from the knowledge graph; the Singapore licence records contain no indication text) |
| Predicted New Indication | Obstructive lung disease |
| TxGNN Prediction Score | 99.71% |
| Evidence Level | L1 |
| Singapore Market Status | ✓ Marketed |
| Number of Registrations | 15 |
| Recommended Decision | Proceed with Guardrails |
Why is This Prediction Reasonable?
Detailed mechanism-of-action data were not available in the data compiled for this report. From established pharmacology, epinephrine is a non-selective alpha/beta-adrenergic agonist. Beta-2 receptor activation relaxes bronchial smooth muscle and causes bronchodilation, while alpha-1 activation reduces mucosal oedema.
Obstructive lung disease covers asthma and chronic obstructive pulmonary disease (COPD). Asthma, emphysema and bronchitis are already among epinephrine's original indications, so this prediction is largely a rediscovery of an existing use rather than a wholly new one. The inhaled HFA metered-dose formulation (E004 / Primatene Mist) has Phase 3 efficacy and safety data in asthma. Evidence in bronchiolitis is mixed and is best treated as a separate sub-question.
Among the other predictions, laryngotracheitis (croup) has the next strongest support (L2). Nebulised epinephrine reduces subglottic oedema, and this is established clinical practice. Food-dependent exercise-induced anaphylaxis (L4) is a subtype of anaphylaxis, an existing indication. Predictions such as Rienhoff syndrome, anorectal stricture, dry eye syndrome, headache disorder and trigeminal autonomic cephalalgia have no clinical trials or no therapeutic rationale and should be held.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT01357642 | Phase 3 | Completed | 373 | 12-week efficacy and safety of epinephrine HFA inhalation aerosol vs placebo and Primatene Mist in adolescents and adults with asthma |
| NCT01476904 | Phase 3 | Completed | 208 | 3-month safety extension (6-month safety profile) of E004 vs placebo in asthma |
| NCT01460511 | Phase 3 | Completed | 70 | 4-week efficacy and safety of E004 vs placebo in children aged 4–11 with asthma |
| NCT01737905 | Phase 3 | Completed | 28 | Single-dose crossover study of E004 in children with asthma |
| NCT01705964 | Phase 4 | Completed | 49 | IM epinephrine as adjunct to inhaled β2 agonists in severe paediatric asthma exacerbation |
| NCT01834820 | Phase 4 | Completed | 120 | Epinephrine, dexamethasone and hypertonic saline in children with bronchiolitis |
| NCT00817466 | Phase 4 | Unknown | 500 | Optimal inhalation treatment for infants with acute bronchiolitis |
| NCT04207840 | Phase 4 | Completed | 28 | Systemic exposure of inhaled Primatene Mist vs IM epinephrine and inhaled albuterol in healthy adults (exposure data, not efficacy) |
| NCT01255709 | Phase 2 | Completed | 24 | Pharmacokinetics of epinephrine HFA inhalation aerosol in healthy volunteers |
| NCT00114478 | N/A | Unknown | 600 | Epinephrine vs albuterol in bronchiolitis |
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 35093318 | 2022 | RCT | The Journal of Pediatrics | Corticosteroids plus nebulised epinephrine vs standard care for bronchiolitis in intensive care, with duration of positive pressure support as the outcome |
| 33893229 | 2021 | Network meta-analysis | Pediatrics | Comparative efficacy of bronchiolitis interventions in acute care |
| 21678340 | 2011 | Cochrane systematic review | Cochrane Database Syst Rev | Epinephrine for bronchiolitis; bronchodilators are widely used despite uncertain effectiveness |
| 14974006 | 2004 | Cochrane systematic review | Cochrane Database Syst Rev | Earlier Cochrane review of epinephrine for bronchiolitis |
| 35953216 | 2022 | Review | Emerg Med Clin North Am | ED evaluation and management of asthma and COPD exacerbations |
| 30488718 | 2019 | Review | Expert Rev Respir Med | Role of racemic epinephrine, corticosteroids, hypertonic saline and high-flow oxygen in infant bronchiolitis |
| 21157348 | 2011 | Review | Curr Opin Pediatr | Update on bronchiolitis management; no treatment has been conclusively shown to alter disease course |
| 11940264 | 2002 | Review | Critical Care | Clinical review of severe asthma |
| 33446622 | 2020 | Drug review | Med Lett Drugs Ther | Drugs for asthma |
| 30856157 | 2019 | Drug review | Med Lett Drugs Ther | OTC Primatene Mist returns |
Singapore Market Information
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| SIN16897P | Adrenaline Aguettant Solution for Injection in Pre-filled Syringe 0.1 mg/ml | Injection, solution | Not recorded |
| SIN10017P | Adrenaline Injection 1:1000 | Injection | Not recorded |
| SIN13290P | EpiPen Junior Auto-Injector 0.15 mg/dose | Injection | Not recorded |
| SIN13288P | EpiPen Auto-Injector 0.3 mg/dose | Injection | Not recorded |
| SIN15913P | Artinibsa 4% with Epinephrine 1:100000 | Injection, solution | Not recorded |
Ten further licences cover local-anaesthetic injections combined with epinephrine. All 15 registrations are valid single-ingredient records, and all are injectable. No inhaled or nebulised epinephrine product appears among them.
Safety Considerations
- Contraindications / disease associations (knowledge graph, not label text): hypertension and cardiovascular disease, coronary artery disease, myocardial infarction, atrial fibrillation and heart conduction disease, sudden cardiac arrest, angle-closure glaucoma, hyperthyroidism, diabetes mellitus and diabetic ketoacidosis, liver and kidney disease, epilepsy, benign prostatic hyperplasia, respiratory failure, myasthenia gravis, and others.
- Drug interactions: 100 interactions were found. Those shown include Major interactions with the tricyclic-type antidepressants amitriptyline and amoxapine. Moderate interactions include beta-blockers (acebutolol, atenolol, betaxolol), other beta-agonists (formoterol, salbutamol, arformoterol), stimulants (amphetamine, methylphenidate, atomoxetine), antipsychotics (aripiprazole, asenapine, amisulpride) and antidiabetic agents (acarbose, acetohexamide, alogliptin, albiglutide).
Package insert warnings and contraindications were not available for this report; please refer to the package insert for label safety information.
Conclusion and Next Steps
Decision: Proceed with Guardrails
Rationale: Several completed Phase 3 trials of inhaled epinephrine in asthma, in adults and children, support this prediction, and asthma, emphysema and bronchitis are already established uses. The new element is mainly the inhaled route, as the Singapore licences are injectable only. The bronchiolitis evidence is mixed and the cardiovascular safety burden is notable.
To proceed, the following is needed:
- Singapore package insert warnings and contraindications
- Mechanism-of-action data from DrugBank
- A regulatory assessment of whether an inhaled epinephrine product could be registered in Singapore, since current licences are injectable only
- A review of the interaction and contraindication burden, especially cardiovascular disease and use with beta-blockers or tricyclic antidepressants
- Treatment of bronchiolitis and croup as separate sub-questions with their own evidence reviews
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.