Open-Label, Multicenter Study of Flecainide Acetate Oral Inhalation Solution for Acute Conversion of Recent-Onset,...

Area of Science:

• Cardiology
• Pharmacology
• Medical Devices

Background:

• Oral and intravenous flecainide are standard treatments for atrial fibrillation cardioversion.
• This study investigated the feasibility of delivering flecainide via oral inhalation for acute conversion.

Purpose of the Study:

• To evaluate the efficacy and safety of inhaled flecainide acetate for rapid cardioversion of recent-onset atrial fibrillation.
• To determine if inhaled flecainide reaches therapeutic plasma concentrations for restoring sinus rhythm.

Main Methods:

• An open-label, dose-escalation study involving 101 patients with recent-onset atrial fibrillation.
• Patients self-administered varying doses of flecainide acetate inhalation solution via nebulizer.
• Efficacy was assessed by electrocardiograms, Holter monitoring, and plasma flecainide concentrations; adverse events were recorded.

Main Results:

• Conversion rates increased with dose, with 48% achieving sinus rhythm within 90 minutes at the highest dose.
• Patients reaching plasma concentrations >200 ng/mL had a 50% conversion rate within 90 minutes.
• Conversion was rapid (median 8.1 minutes post-inhalation), and 86% of responders experienced symptom resolution. Mild, transient adverse events like cough were common; serious cardiac events were rare.

Conclusions:

• Oral inhalation of flecainide acetate is a safe and effective method for acute cardioversion of recent-onset atrial fibrillation.
• The inhaled route achieves sufficient plasma concentrations for rapid restoration of sinus rhythm.
• This delivery method offers a promising alternative for atrial fibrillation management.