Propranolol
| Evidence Level: L2 | Predicted Indications: 6 |
Table of Contents
Propranolol: From Hypertension/Arrhythmia to Cardiomyopathy
One-Sentence Summary
Propranolol is a non-selective β-adrenergic blocker with a long history of use in hypertension, angina, and arrhythmias. Among 6 candidate indications generated by the TxGNN model for this drug, Cardiomyopathy (specifically hypertrophic/hypertrophic obstructive cardiomyopathy, HCM/HOCM) stands out with by far the strongest supporting evidence — 3 clinical trials and 20 publications, including a double-blind RCT — while the other 5 candidates (e.g. distal myopathy, congenital myopathy, chondroma) have no clinical or literature support at all (L4–L5, Hold). This report therefore focuses on Cardiomyopathy as the actionable candidate.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Hypertension, angina pectoris, cardiac arrhythmia (non-selective β-blocker) — no India-specific regulatory indication text is available in this evidence pack |
| Predicted New Indication | Cardiomyopathy (hypertrophic/hypertrophic obstructive cardiomyopathy) |
| TxGNN Prediction Score | 99.12% |
| Evidence Level | L2 |
| India Market Status | Not marketed (Not Marketed) |
| Number of Registrations | 0 |
| Recommended Decision | Proceed with Guardrails |
Why is This Prediction Reasonable?
Detailed DrugBank mechanism-of-action data is not available in this evidence pack (flagged as data gap DG002, High severity). Based on well-established pharmacology, propranolol is a non-selective β1/β2-adrenergic receptor antagonist: it reduces myocardial contractility, heart rate, and myocardial oxygen demand. This mechanism is directly relevant to hypertrophic cardiomyopathy, where reducing left ventricular outflow tract (LVOT) gradient and improving diastolic filling relieve symptoms.
The link between the original indications (hypertension, arrhythmia) and the new indication (cardiomyopathy) is mechanistically close rather than speculative — both involve cardiac autonomic/adrenergic overactivity. This is reflected in the literature: propranolol has been an off-label mainstay for symptomatic HCM/HOCM management for decades, including a 1973 double-blind RCT (PMID 4586631) and multiple hemodynamic cohort studies from the 1980s–1990s.
It is worth noting that current international HCM treatment guidelines are gradually shifting toward cardiac myosin inhibitors (e.g., mavacamten) as first-line therapy, positioning propranolol as an established but no longer cutting-edge option. Compared with the drug’s other 5 TxGNN-predicted candidates in this pack — all rated L3–L5 with “Hold” and no clinical trial or literature support — Cardiomyopathy is the only candidate with a coherent, evidence-backed mechanistic story.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT05019027 | Phase 4 | Enrolling by Invitation | 20 | N-of-1 trials testing whether patients with transthyretin cardiac amyloidosis feel better when their beta-blocker is deprescribed (feasibility/deprescribing study, not an efficacy trial) |
| NCT04767061 | Phase 4 | Completed | 9 | N-of-1 trials on deprescribing beta-blockers in HFpEF patients, evaluating impact on physical function |
| NCT05427474 | Phase 3 | Unknown | 90 | Combined propranolol + gabapentin for paroxysmal sympathetic hyperactivity after traumatic brain injury (not cardiomyopathy itself; status unknown) |
Note: none of these trials directly test propranolol for treating cardiomyopathy — all relate to deprescribing or an unrelated indication (PSH post-TBI).
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 4586631 | 1973 | RCT | British Heart Journal | Double-blind trial of propranolol vs practolol in hypertrophic cardiomyopathy (no abstract available; title indicates head-to-head comparative RCT) |
| 7191199 | 1980 | Review | The American Journal of Cardiology | Review of propranolol’s role in controlling arrhythmia in hypertrophic cardiomyopathy |
| 7200796 | 1982 | Cohort | British Heart Journal | In 12 HOCM patients, combined nifedipine+propranolol reduced LV peak systolic pressure more than nifedipine alone |
| 1611637 | 1992 | Cohort | Cardiology | In 19 HCM patients, LV function at rest/exercise assessed via radionuclide ventriculography after propranolol and disopyramide |
| 3673167 | 1987 | Cohort | Zeitschrift für Kardiologie | 15 HCM patients treated with oral nifedipine+propranolol for 6–24 months; some discontinued due to deterioration/side effects |
| 3433863 | 1987 | Cohort | Zeitschrift für Kardiologie | Companion analysis of nifedipine+propranolol combination therapy in 15 HCM patients |
| 10460081 | 1999 | Case Report | Pediatric Emergency Care | 16-year-old developed acute dilated cardiomyopathy and CNS toxicity after propranolol overdose (3200 mg, suicide attempt) — a safety signal at supratherapeutic doses |
| 36104228 | 2022 | Case Report | International Heart Journal | Infant with mitochondrial cardiomyopathy and LVOT stenosis treated with low-dose propranolol + cibenzoline |
India Market Information
Propranolol currently has 0 registered licenses and is not marketed in India (市場狀態: Not marketed) according to this evidence pack. No authorization records are available to summarize.
Safety Considerations
Drug Interactions: DDI query returned 307 total interactions on record. Notable entries include:
- Major: Epinephrine
- Moderate: Hydrocortisone, Methscopolamine, Hyoscyamine, Bupropion, Triamcinolone, Morphine, Atropine, Dexamethasone, Lorcaserin, Betamethasone, Calcium Phosphate, Budesonide, Calcium acetate, Canagliflozin, Chlorpropamide, Cimetidine
- Minor: Ascorbic acid, Acetylsalicylic acid, Magnesium oxide
Formal package-insert warnings and contraindications are not yet available for this drug (data gap DG001, Blocking severity) and are omitted here pending retrieval from an official regulatory source.
Conclusion and Next Steps
Decision: Proceed with Guardrails
Rationale: Propranolol’s use in HCM/HOCM is supported by a double-blind RCT and multiple hemodynamic cohort studies spanning decades — the strongest evidence tier (L2) among all six TxGNN-predicted candidates for this drug. However, the drug is not currently marketed in India, formal safety labeling is unavailable, and current international HCM guidelines are shifting toward newer first-line agents.
To proceed, the following is needed:
- Official TFDA/CDSCO package insert data to resolve the blocking safety data gap (DG001)
- Formal mechanism-of-action documentation from DrugBank or equivalent source (DG002)
- Confirmation of route/dosage form compatibility for HCM dosing, since route data is currently marked “pending”
- Regulatory pathway assessment given the drug has no existing marketing authorization in India
- Clarification of positioning relative to newer first-line HCM therapies (e.g., cardiac myosin inhibitors)
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.