Efficacy and safety of celivarone, with amiodarone as calibrator, in patients with an implantable cardioverter-defibrillator for prevention of implantable cardioverter-defibrillator interventions or death: the ALPHEE study.

BACKGROUND: Celivarone is a new antiarrhythmic agent developed for the treatment of ventricular arrhythmias. This study investigated the efficacy and safety of celivarone in preventing implantable cardioverter-defibrillator (ICD) interventions or death. METHODS AND RESULTS: Celivarone (50, 100, or 300 mg/d) was assessed compared with placebo in this randomized, double-blind, placebo-controlled, parallel-group study. Amiodarone (200 mg/d after loading dose of 600 mg/d for 10 days) was used as a calibrator. A total of 486 patients with a left ventricular ejection fraction ≤40% and at least 1 ICD intervention for ventricular tachycardia or ventricular fibrillation in the previous month or ICD implantation in the previous month for documented ventricular tachycardia/ventricular fibrillation were randomized. Median treatment duration was 9 months. The primary efficacy end point was occurrence of ventricular tachycardia/ventricular fibrillation-triggered ICD interventions (shocks or antitachycardia pacing) or sudden death. The proportion of patients experiencing an appropriate ICD intervention or sudden death was 61.5% in the placebo group; 67.0%, 58.8%, and 54.9% in the celivarone 50-, 100-, and 300-mg groups, respectively; and 45.3% in the amiodarone group. Hazard ratios versus placebo for the primary end point ranged from 0.860 for celivarone 300 mg to 1.199 for celivarone 50 mg. None of the comparisons versus placebo were statistically significant. Celivarone had an acceptable safety profile. CONCLUSIONS: Celivarone was not effective for the prevention of ICD interventions or sudden death. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrials.gov. Unique identifier: NCT00993382.

Celivarone for maintenance of sinus rhythm and conversion of atrial fibrillation/flutter.

INTRODUCTION: Celivarone, a new noniodinated benzofuran derivative pharmacologically related to dronedarone and amiodarone, has been shown to have antiarrhythmic properties at a molecular level. The purpose of the 2 trials presented here (MAIA and CORYFEE) was to assess celivarone efficacy in the maintenance of sinus rhythm postcardioversion and for the conversion of atrial fibrillation (AF)/atrial flutter (AFL). METHODS AND RESULTS: In the MAIA trial, 673 patients with AF/AFL recently converted to sinus rhythm were randomly assigned to receive 50, 100, 200, or 300 mg once-daily dosing of celivarone; 200 mg daily of amiodarone preceded by a loading dose of 600 mg for 10 days; or placebo. At 3 months' follow up, no significant difference was observed in time to AF/AFL relapse among the various celivarone groups and placebo. However, fewer symptomatic AF/AFL recurrences were observed in the lower-dose celivarone groups (26.6% for celivarone 50 mg [P = 0.022] and 25.2% for celivarone 100 mg [P = 0.018] vs 40.5% for placebo at 90 days). Fewer adverse events were observed with the use of celivarone and placebo than amiodarone. In the CORYFEE study, 150 patients with AF/AFL were randomly assigned to once-daily celivarone dosing of 300 or 600 mg, or placebo, for a 2-day treatment period. There was no significant difference in the rate of spontaneous conversion to sinus rhythm between the treatment and control groups. CONCLUSIONS: In these studies, celivarone does not appear to be efficacious in the maintenance of sinus rhythm in AF/AFL patients or for the conversion of AF/AFL patients.

Dronedarone for maintenance of sinus rhythm in atrial fibrillation or flutter.

BACKGROUND: Amiodarone is effective in maintaining sinus rhythm in atrial fibrillation but is associated with potentially serious toxic effects. Dronedarone is a new antiarrhythmic agent pharmacologically related to amiodarone but developed to reduce the risk of side effects. METHODS: In two identical multicenter, double-blind, randomized trials, one conducted in Europe (ClinicalTrials.gov number, NCT00259428 [ClinicalTrials.gov] ) and one conducted in the United States, Canada, Australia, South Africa, and Argentina (termed the non-European trial, NCT00259376 [ClinicalTrials.gov] ), we evaluated the efficacy of dronedarone, with 828 patients receiving 400 mg of the drug twice daily and 409 patients receiving placebo. Rhythm was monitored transtelephonically on days 2, 3, and 5; at 3, 5, 7, and 10 months; during recurrence of arrhythmia; and at nine scheduled visits during a 12-month period. The primary end point was the time to the first recurrence of atrial fibrillation or flutter. RESULTS: In the European trial, the median times to the recurrence of arrhythmia were 41 days in the placebo group and 96 days in the dronedarone group (P=0.01). The corresponding durations in the non-European trial were 59 and 158 days (P=0.002). At the recurrence of arrhythmia in the European trial, the mean (+/-SD) ventricular rate was 117.5+/-29.1 beats per minute in the placebo group and 102.3+/-24.7 beats per minute in the dronedarone group (P<0.001); the corresponding rates in the non-European trial were 116.6+/-31.9 and 104.6+/-27.1 beats per minute (P<0.001). Rates of pulmonary toxic effects and of thyroid and liver dysfunction were not significantly increased in the dronedarone group. CONCLUSIONS: Dronedarone was significantly more effective than placebo in maintaining sinus rhythm and in reducing the ventricular rate during recurrence of arrhythmia.

Efficacy and safety of dronedarone in patients previously treated with other antiarrhythmic agents.

BACKGROUND: Currently available antiarrhythmic drugs (AADs) for the prevention of atrial fibrillation (AF)/atrial flutter (AFL) suffer from incomplete efficacy and poor tolerability. HYPOTHESIS: Dronedarone could represent an effective and safe option in patients previously treated with AADs, especially class Ic AADs and sotalol. METHODS: Retrospective analysis of 2 double-blind, parallel-group trials (EURIDIS [European Trial in Atrial Fibrillation or Flutter Patients Receiving Dronedarone for the Maintenance of Sinus Rhythm] and ADONIS [American-Australian-African Trial With Dronedarone in Atrial Fibrillation or Flutter Patients for the Maintenance of Sinus Rhythm]) comparing the efficacy and safety of dronedarone with placebo over 12 months. The primary end point was AF/AFL recurrence in patients previously treated with another AAD that was discontinued for whatever reason prior to randomization. RESULTS: In patients previously treated with any AADs, dronedarone decreased the risk of AF recurrence by 30.4% vs placebo (hazard ratio [HR]: 0.70; 95% confidence interval [CI]: 0.59-0.82; P < 0.001). In patients previously treated with a class Ic agent, dronedarone decreased the risk of recurrence by 31.4% (HR: 0.69; 95% CI: 0.53-0.89; P = 0.004), whereas in patients previously treated with sotalol, dronedarone showed a trend toward a decrease of risk of recurrence (HR: 0.86; 95% CI: 0.67-1.11; P = 0.244). Dronedarone was equally effective irrespective of whether class Ic or sotalol were stopped for lack of efficacy or adverse events (AEs). Discontinuation rates were similar in the 2 groups (55.9% vs 43.1%), as were incidence of AEs and serious AEs. CONCLUSIONS: Dronedarone seems to be effective in preventing AF recurrences in patients without permanent AF previously treated with other AADs, even if those were discontinued for lack of efficacy. Dronedarone appears to be well tolerated even in patients who already had tolerability issues with AADs.

Celivarone in patients with an implantable cardioverter-defibrillator: adjunctive therapy for the reduction of ventricular arrhythmia-triggered implantable cardioverter-defibrillator interventions.

BACKGROUND: Implantable cardioverter-defibrillators (ICDs) remain the treatment of choice for the prevention of life-threatening arrhythmias. However, many patients with ICDs require additional antiarrhythmic therapy to reduce the morbidity associated with recurrent arrhythmia-triggered ICD interventions. OBJECTIVE: Our study aimed to evaluate the safety and efficacy of celivarone in reducing these interventions. METHODS: A total of 153 eligible ICD recipients were randomized to receive either placebo or celivarone 100 or 300 mg once daily for 6 months. The primary end point was the prevention of arrhythmia-triggered ICD therapies. RESULTS: Fewer ventricular tachycardia and ventricular fibrillation episodes were observed in the 300-mg celivarone group than in the placebo group, with a relative risk reduction of 46%, which was not statistically significant. The analysis of all-cause shocks showed a trend toward a decreased number of events in the celivarone 300-mg group. A post hoc analysis of the primary end point in a subgroup of patients in the celivarone 300-mg group, who had received ICD therapy within 1 month of randomization, showed a significant benefit (P = .032). Celivarone was not associated with an increased risk of torsades de pointes, thyroid dysfunction, or pulmonary events. More heart failure events were reported in the celivarone groups than in the placebo group, but the difference was not statistically significant. CONCLUSION: Celivarone tends to reduce ventricular tachycardia-/ventricular fibrillation-triggered ICD therapies. This effect was not statistically significant. There was a trend toward greater efficacy in the 300-mg group, especially in patients undergoing ICD therapy within 30 days prior to randomization. Overall, celivarone was well tolerated.