Amiodarone and Dronedarone Causes Liver Injury with Distinctly Different Clinical Presentations.

OBJECTIVE: To describe hepatotoxicity due to amiodarone and dronedarone from the DILIN and the US FDA's surveillance database. METHODS: Hepatotoxicity due to amiodarone and dronedarone enrolled in the U.S. Drug Induced Liver Injury Network (DILIN) from 2004 to 2020 are described. Dronedarone hepatotoxicity cases associated with liver biopsy results were obtained from the FDA Adverse Event Reporting System (FAERS) from 2009 to 2020. RESULTS: Among DILIN's 10 amiodarone and 3 dronedarone DILIN cases, the latency for amiodarone was longer than with dronedarone (388 vs 119 days, p = 0.50) and the median ALT at DILI onset was significantly lower with amiodarone (118 vs 1191 U/L, p = 0.05). Liver biopsies in five amiodarone cases showed fibrosis, steatosis, and numerous Mallory-Denk bodies. Five patients died although only one from liver failure. One patient with dronedarone induced liver injury died of a non-liver related cause. Nine additional cases of DILI due to dronedarone requiring hospitalization were identified in the FAERS database. Three patients developed liver injury within a month of starting the medication. Two developed acute liver failure and underwent urgent liver transplant, one was evaluated for liver transplant but then recovered spontaneously, while one patient with cirrhosis died of liver related causes. CONCLUSION: Amiodarone hepatotoxicity resembles that seen in alcohol related liver injury, with fatty infiltration and inflammation. Dronedarone is less predictable, typically without fat and with a shorter latency of use before presentation. These differences may be explained, in part, by the differing pharmacokinetics of the two drugs leading to different mechanisms of hepatotoxicity.

Dronedarone Enhances the Antibacterial Activity of Polymyxin B and Inhibits the Quorum Sensing System by Interacting with LuxS.

Quorum sensing (QS) is considered an appealing target for interference with bacterial infections. ß-Adrenergic blockers are promising anti-QS agents but do not have antibacterial activity. We assessed the potential ability of adrenergic receptor inhibitors to enhance the antibacterial activity of polymyxin B (PB) against Klebsiella pneumoniae and determined that dronedarone has the most potent activity both in vitro and in vivo. We found that dronedarone increases the thermal stability of LuxS, decreases the production of AI-2, and affects the biofilm formation of K. pneumoniae. We also identified the direct binding of dronedarone to LuxS. However, the mechanism by which dronedarone enhances the antibacterial activity of PB has not been elucidated and is worthy of further exploration. Our study provides a basis for the future development of drug combination regimens.

Chapter 3: Evidence for the Use of Early Rhythm Control to Prevent Atrial Fibrillation Progression.

This chapter reviews atrial fibrillation (AF) progression and its associated mechanisms, including comorbidities and AF as contributors to atrial myopathy, and atrial myopathy as a contributing factor to AF progression. In addition, the chapter discusses the concept of comorbidities and atrial myopathy as synergistic contributors to adverse outcomes, the notion of "AF begets AF," and the consequences of AF burden if left untreated. Clinical trials evaluating outcomes with antiarrhythmic drugs (AADs) compared with placebo have demonstrated efficacy, but also reveal a possible proarrhythmic and mortality risk if AAD selection is not appropriate and patients are not correctly identified based on risk factors and comorbidities. Data from ATHENA, the first and only trial to demonstrate that an AAD (dronedarone) can reduce cardiovascular (CV) hospitalizations in people with AF, are reviewed, along with studies reporting on the use of catheter ablation versus AADs for AF rhythm control. Finally, recent data showing a reduction in major adverse outcomes if rhythm control is initiated early are summarized, including results from the EAST-AFNET 4 trial, as well as confirmatory results from several large "real-world" trials. Chapter 3 is summarized as follows.

Chapter 2: Rate Versus Rhythm Control.

Atrial fibrillation (AF) is a potentially serious health risk, both because of its symptoms and because of its association with an increased risk for heart failure, hospitalization, thromboembolism, and death. Chapter 2 discusses selection of appropriate treatments and when to initiate these therapies. Older trials focused on comparing rate versus rhythm control treatment options for AF. It is now recognized that both rate and rhythm control are important and can be used together. This chapter reviews the historical, pivotal rate versus rhythm control trials that failed to show any overall survival benefit of rhythm over rate control, as well as the trials' now-recognized limitations with respect to modern therapy. In addition, an in-depth discussion of the more recent trials of antiarrhythmic drugs (AAD) and ablation techniques (which have become available since the original rate versus rhythm trials were performed) is included. These updated trials show that when applied to patient- and disease-specific situations, rhythm control can reduce the risk for mortality and hospitalization. The chapter also reviews the guidelines that have been developed to achieve these goals. Chapter 2 is summarized as follows: (1) Rate control is needed (at rest and during exertion) to reduce rate-related symptoms when rhythm control is ineffective or incomplete and to prevent a tachycardia-induced cardiomyopathy. (2) Previous trials with pharmacological therapy alone comparing rate versus rhythm control using the AADs available at that time failed to show any overall survival benefit of rhythm control over rate control. (3) These earlier trials had many methodological limitations and enrolled participants who did not have access to modern therapies. (4) Newer therapies, including those for stroke prevention, dronedarone (the latest approved AAD), and AF ablation, have improved the safety and efficacy of rhythm control strategies.

Dronedarone Versus Sotalol in Antiarrhythmic Drug-Naive Veterans With Atrial Fibrillation.

BACKGROUND: Sotalol and dronedarone are both used for maintenance of sinus rhythm for patients with atrial fibrillation. However, while sotalol requires initial monitoring for QT prolongation and proarrhythmia, dronedarone does not. These treatments can be used in comparable patients, but their safety and effectiveness have not been compared head to head. Therefore, we retrospectively evaluated the effectiveness and safety using data from a large health care system. METHODS: Using Veterans Health Administration data, we identified 11 296 antiarrhythmic drug-naive patients with atrial fibrillation prescribed dronedarone or sotalol in 2012 or later. We excluded patients with prior conduction disease, pacemakers or implantable cardioverter-defibrillators, ventricular arrhythmia, cancer, renal failure, liver disease, or heart failure. We used natural language processing to identify and compare baseline left ventricular ejection fraction between treatment arms. We used 1:1 propensity score matching, based on patient demographics, comorbidities, and medications, and Cox regression to compare strategies. To evaluate residual confounding, we performed falsification analysis with nonplausible outcomes. RESULTS: The matched cohort comprised 6212 patients (3106 dronedarone and 3106 sotalol; mean [±SD] age, 71±10 years; 2.5% female; mean [±SD] CHA2DS2-VASC, 2±1.3). The mean (±SD) left ventricular ejection fraction was 55±11 and 58±10 for dronedarone and sotalol users, correspondingly. Dronedarone, compared with sotalol, did not demonstrate a significant association with risk of cardiovascular hospitalization (hazard ratio, 1.03 [95% CI, 0.88-1.21]) or all-cause mortality (hazard ratio, 0.89 [95% CI, 0.68-1.16]). However, dronedarone was associated with significantly lower risk of ventricular proarrhythmic events (hazard ratio, 0.53 [95% CI, 0.38-0.74]) and symptomatic bradycardia (hazard ratio, 0.56 [95% CI, 0.37-0.87]). The primary findings were stable across sensitivity analyses. Falsification analyses were not significant. CONCLUSIONS: Dronedarone, compared with sotalol, was associated with a lower risk of ventricular proarrhythmic events and conduction disorders while having no difference in risk of incident cardiovascular hospitalization and mortality. These observational data provide the basis for prospective efficacy and safety trials.

Clinical and economic outcomes associated with use of anti-arrhythmic drugs versus ablation in atrial fibrillation.

Aim: To evaluate the clinical and economic impact of antiarrhythmic drugs (AADs) compared with ablation both as individual treatments and as combination therapy without/with considering the order of treatment among patients with atrial fibrillation (AFib). Materials & methods: A budget impact model over a one-year time horizon was developed to assess the economic impact of AADs (amiodarone, dofetilide, dronedarone, flecainide, propafenone, sotalol, and as a group) versus ablation across three scenarios: direct comparisons of individual treatments, non-temporal combinations, and temporal combinations. The economic analysis was conducted in accordance with CHEERS guidance as per current model objectives. Results are reported as costs per patient per year (PPPY). The impact of individual parameters was evaluated using one-way sensitivity analysis (OWSA). Results: In direct comparisons, ablation had the highest annual medication/procedure cost ($29,432), followed by dofetilide ($7661), dronedarone ($6451), sotalol ($4552), propafenone ($3044), flecainide ($2563), and amiodarone ($2538). Flecainide had the highest costs for long-term clinical outcomes ($22,964), followed by dofetilide ($17,462), sotalol ($15,030), amiodarone ($12,450), dronedarone ($10,424), propafenone ($7678) and ablation ($9948). In the non-temporal scenario, total costs incurred for AADs (group) + ablation ($17,278) were lower compared with ablation alone ($39,380). In the temporal scenario, AADs (group) before ablation resulted in PPPY cost savings of ($22,858) compared with AADs (group) after ablation ($19,958). Key factors in OWSA were ablation costs, the proportion of patients having reablation, and withdrawal due to adverse events. Conclusion: Utilization of AADs as individual treatment or in combination with ablation demonstrated comparable clinical benefits along with costs savings in patients with AFib.

Dronedarone versus sotalol in patients with atrial fibrillation: A systematic literature review and network meta-analysis.

BACKGROUND: There are limited comparative data on safety and efficacy within commonly used Vaughan-Williams (VW) class III antiarrhythmic drugs (AADs) for maintenance of sinus rhythm in adults with atrial fibrillation (AF). HYPOTHESIS: We hypothesized that dronedarone and sotalol, two commonly prescribed VW class III AADs with class II properties, have different safety and efficacy effects in patients with nonpermanent AF. METHODS: A systematic literature review was conducted searching MEDLINE®, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) up to June 15, 2021 (NCT05279833). Clinical trials and observational studies that evaluated safety and efficacy of dronedarone or sotalol in adults with AF were included. Bayesian random-effects network meta-analysis (NMA) was used to quantify comparative safety and efficacy. Where feasible, we performed sensitivity analyses by including only randomized controlled trials (RCTs). RESULTS: Of 3581 records identified through database searches, 37 unique studies (23 RCTs, 13 observational studies, and 1 nonrandomized trial) were included in the NMA. Dronedarone was associated with a statistically significantly lower risk of all-cause death versus sotalol (hazard ratio [HR] = 0.38 [95% credible interval, CrI: 0.19, 0.74]). The association was numerically similar in the sensitivity analysis (HR = 0.46 [95% CrI: 0.21, 1.02]). AF recurrence and cardiovascular death results were not significantly different between dronedarone and sotalol in all-studies and sensitivity analyses. CONCLUSION: The NMA findings indicate that, across all clinical trials and observational studies included, dronedarone compared with sotalol was associated with a lower risk of all-cause death, but with no difference in AF recurrence.

FDA approved drugs with antiviral activity against SARS-CoV-2: From structure-based repurposing to host-specific mechanisms.

The continuing heavy toll of the COVID-19 pandemic necessitates development of therapeutic options. We adopted structure-based drug repurposing to screen FDA-approved drugs for inhibitory effects against main protease enzyme (Mpro) substrate-binding pocket of SARS-CoV-2 for non-covalent and covalent binding. Top candidates were screened against infectious SARS-CoV-2 in a cell-based viral replication assay. Promising candidates included atovaquone, mebendazole, ouabain, dronedarone, and entacapone, although atovaquone and mebendazole were the only two candidates with IC50s that fall within their therapeutic plasma concentration. Additionally, we performed Mpro assays on the top hits, which demonstrated inhibition of Mpro by dronedarone (IC50 18 µM), mebendazole (IC50 19 µM) and entacapone (IC50 9 µM). Atovaquone showed only modest Mpro inhibition, and thus we explored other potential mechanisms. Although atovaquone is Dihydroorotate dehydrogenase (DHODH) inhibitor, we did not observe inhibition of DHODH at the respective SARS-CoV-2 IC50. Metabolomic profiling of atovaquone treated cells showed dysregulation of purine metabolism pathway metabolite, where ecto-5'-nucleotidase (NT5E) was downregulated by atovaquone at concentrations equivalent to its antiviral IC50. Atovaquone and mebendazole are promising candidates with SARS-CoV-2 antiviral activity. While mebendazole does appear to target Mpro, atovaquone may inhibit SARS-CoV-2 viral replication by targeting host purine metabolism.

A value-based budget impact model for dronedarone compared with other rhythm control strategies.

Aim: The budgetary consequences of increasing dronedarone utilization for treatment of atrial fibrillation were evaluated from a US payer perspective. Materials & methods: A budget impact model over a 5-year time horizon was developed, including drug-related costs and risks for long-term clinical outcomes (LTCOs). Treatments included antiarrhythmic drugs (AADs; dronedarone, amiodarone, sotalol, propafenone, dofetilide, flecainide), rate control medications, and ablation. Direct comparisons and temporal and non-temporal combination scenarios investigating treatment order were analyzed as costs per patient per month (PPPM). Results: By projected year 5, costs PPPM for dronedarone versus other AADs decreased by $37.69 due to fewer LTCOs, treatment with dronedarone versus ablation or rate control medications + ablation resulted in cost savings ($359.94 and $370.54, respectively), and AADs placed before ablation decreased PPPM costs by $242 compared with ablation before AADs. Conclusion Increased dronedarone utilization demonstrated incremental cost reductions over time.

Cardiovascular outcomes in patients with atrial fibrillation concomitantly treated with antiarrhythmic drugs and non-vitamin k antagonist oral anticoagulants.

AIMS: Limited data compared antiarrhythmic drugs (AADs) with concomitant non-vitamin K antagonist oral anticoagulants in atrial fibrillation patients, hence the aim of the study. METHODS AND RESULTS: National health insurance database were retrieved during 2012-17 for study. We excluded patients not taking AADs, bradycardia, heart block, heart failure admission, mitral stenosis, prosthetic valve, incomplete demographic data, and follow-up <3 months. Outcomes were compared in Protocol 1, dronedarone vs. non-dronedarone; Protocol 2, dronedarone vs. amiodarone; and Protocol 3, dronedarone vs. propafenone. Outcomes were acute myocardial infarction (AMI), ischaemic stroke/systemic embolism, intracranial haemorrhage (ICH), major bleeding, cardiovascular death, all-cause mortality, and major adverse cardiovascular event (MACE) (including AMI, ischaemic stroke, and cardiovascular death). In Protocol 1, 2298 dronedarone users and 6984 non-dronedarone users (amiodarone = 4844; propafenone = 1914; flecainide = 75; sotalol = 61) were analysed. Dronedarone was associated with lower ICH (HR = 0.61, 95% CI = 0.38-0.99, P = 0.0436), cardiovascular death (HR = 0.24, 95% CI = 0.16-0.37, P < 0.0001), all-cause mortality (HR = 0.33, 95% CI = 0.27-0.42, P < 0.0001), and MACE (HR = 0.56, 95% CI = 0.45-0.70, P < 0.0001). In Protocol 2, 2231 dronedarone users and 6693 amiodarone users were analysed. Dronedarone was associated with significantly lower ICH (HR = 0.53, 95%=CI 0.33-0.84, P = 0.0078), cardiovascular death (HR = 0.20, 95% CI = 0.13-0.31, P < 0.0001), all-cause mortality (HR 0.27, 95% CI 0.22-0.34, P < 0.0001), and MACE (HR = 0.53, 95% CI = 0.43-0.66, P < 0.0001), compared with amiodarone. In Protocol 3, 812 dronedarone users and 2436 propafenone users were analysed. There were no differences between two drugs for primary and secondary outcomes. CONCLUSION: The use of dronedarone with NOACs was associated with cardiovascular benefits in an Asian population, compared with non-dronedarone AADs and amiodarone.

Effect of dronedarone vs. placebo on atrial fibrillation progression: a post hoc analysis from ATHENA trial.

AIMS: This post hoc analysis of the ATHENA trial (NCT00174785) assessed the effect of dronedarone on the estimated burden of atrial fibrillation (AF)/atrial flutter (AFL) progression to presumed permanent AF/AFL, and regression to sinus rhythm (SR), compared with placebo. METHODS AND RESULTS: The burden of AF/AFL was estimated by a modified Rosendaal method using available electrocardiograms (ECG). Cumulative incidence of permanent AF/AFL (defined as ≥6 months of AF/AFL until end of study) or permanent SR (defined as ≥6 months of SR until end of study) were calculated using Kaplan-Meier estimates. A log-rank test was used to assess statistical significance. Hazard ratios (HRs) with corresponding 95% confidence intervals (CIs) were estimated using a Cox model, adjusted for treatment group. Of the 4439 patients included in this analysis, 2208 received dronedarone, and 2231 placebo. Baseline and clinical characteristics were well balanced between groups. Overall, 304 (13.8%) dronedarone-treated patients progressed to permanent AF/AFL compared with 455 (20.4%) treated with placebo (P < 0.0001). Compared with those receiving placebo, patients receiving dronedarone had a lower cumulative incidence of permanent AF/AFL (log-rank P < 0.001; HR: 0.65; 95% CI: 0.56-0.75), a higher cumulative incidence of permanent SR (log-rank P < 0.001; HR: 1.19; 95% CI: 1.09-1.29), and a lower estimated AF/AFL burden over time (P < 0.01 from Day 14 to Month 21). CONCLUSION: These results suggest that dronedarone could be a useful antiarrhythmic drug for early rhythm control due to less AF/AFL progression and more regression to SR vs. placebo, potentially reflecting reverse remodeling. CLINICAL TRIAL REGISTRATION: NCT00174785.

Development and verification of a physiologically based pharmacokinetic model of dronedarone and its active metabolite N-desbutyldronedarone: Application to prospective simulation of complex drug-drug interaction with rivaroxaban.

AIMS: Despite potential enzyme- and transporter-mediated drug-drug interactions (DDIs) between dronedarone and rivaroxaban in atrial fibrillation (AF) patients, pharmacokinetic/pharmacodynamic data remain limited to guide clinical practice. We aimed to develop, verify and validate a physiologically based pharmacokinetic (PBPK) model of dronedarone and its major metabolite, N-desbutyldronedarone (NDBD), to prospectively interrogate this clinically relevant DDI in healthy and mild renal impairment populations. METHODS: The middle-out development of our PBPK model combined literature-derived or in-house in vitro data, predicted in silico data and in vivo clinical data. Model verification was performed for intravenous and oral (single and multiple) dosing regimens. Model validation for the accurate prediction of cytochrome P450 (CYP)3A4- and P-glycoprotein-mediated DDI utilized simvastatin and digoxin as respective victim drugs. Rivaroxaban-specific inhibitory parameters of dronedarone and/or NDBD against CYP3A4, CYP2J2, OAT3 and P-glycoprotein were incorporated into the PBPK-DDI model for prospective dronedarone-rivaroxaban DDI simulation. RESULTS: Dronedarone and NDBD PK following clinically relevant doses of 400 mg dronedarone across single and multiple oral dosing were accurately simulated by incorporating effect of auto-inactivation on dose nonlinearities. Following successful model validation, nondose-adjusted rivaroxaban-dronedarone DDI in healthy and mild renal impairment populations revealed simulated rivaroxaban area under the plasma concentration-time curve up to 24 h fold change greater than dose exposure equivalence (0.70-1.43) at 1.65 and 1.84, respectively. Correspondingly, respective major bleeding risk was 4.24 and 4.70% compared with threshold of 4.5% representing contraindicated rivaroxaban-ketoconazole DDI. CONCLUSION: Our PBPK-DDI model predicted clinically significant dronedarone-rivaroxaban DDI in both healthy and mild renal impairment subjects. Greater benefit vs. risk could be achieved with rivaroxaban dose reductions to at least 15 mg in mild renal impairment subjects on concomitant dronedarone and rivaroxaban.

Novel methodology for the evaluation of symptoms reported by patients with newly diagnosed atrial fibrillation: Application of natural language processing to electronic medical records data.

INTRODUCTION: Understanding symptom patterns in atrial fibrillation (AF) can help in disease management. We report on the application of natural language processing (NLP) to electronic medical records (EMRs) to capture symptom reports in patients with newly diagnosed (incident) AF. METHODS AND RESULTS: This observational retrospective study included adult patients with an index diagnosis of incident AF during January 1, 2016 through June 30, 2018, in the Optum datasets. The baseline and follow-up periods were 1 year before/after the index date, respectively. The primary objective was identification of the following predefined symptom reports: dyspnea or shortness of breath; syncope, presyncope, lightheadedness, or dizziness; chest pain; fatigue; and palpitations. In an exploratory analysis, the incidence rates of symptom reports and cardiovascular hospitalization were assessed in propensity-matched patient cohorts with incident AF receiving first-line dronedarone or sotalol. Among 30 447 patients with an index AF diagnosis, the NLP algorithm identified at least 1 predefined symptom in 9734 (31.9%) patients. The incidence rate of symptom reports was highest at 0-3 months post-diagnosis and lower at >3-6 and >6-12 months (pre-defined timepoints). Across all time periods, the most common symptoms were dyspnea or shortness of breath, followed by syncope, presyncope, lightheadedness, or dizziness. Similar temporal patterns of symptom reports were observed among patients with prescriptions for dronedarone or sotalol as first-line treatment. CONCLUSION: This study illustrates that NLP can be applied to EMR data to characterize symptom reports in patients with incident AF, and the potential for these methods to inform comparative effectiveness.

Efficacy and Safety of Sustained-Release Metoprolol With Dronedarone After Radiofrequency Ablation of Paroxysmal Atrial Fibrillation: A Propensity Matched Analysis.

The high early recurrence (ER) rate after radiofrequency catheter ablation (RFCA) seriously affects the prognosis of patients with atrial fibrillation (AF), and there are still controversies regarding the best preventive drugs for postoperative recurrence. A single-center retrospective study was conducted on patients with paroxysmal atrial fibrillation (PAF) who received metoprolol sustained-release tablets combined with dronedarone (observation group) and dronedarone alone (control group) after the first RFCA. A matching cohort was established using a 1:1 propensity score matching method to compare the incidence of ER, cardiac function, inflammation level, quality of life (QoL), and antiarrhythmic drugs (AADs)-related adverse reactions between groups. A total of 56 pairs of patients were successfully matched. The incidence of ER in the observation group was significantly lower than that in the control group (32% vs 14%, p = 0.033); the left atrial diameter in the observation group was significantly lower than that in the control group on Day 90 after RFCA (38 ±4 vs 40 ± 5, p = 0.021), and the QoL of the observation group was significantly improved on the thirtieth and ninetieth days after RFCA compared with the control group (72 ± 5 vs 69 ± 9, p = 0.031; 73 ± 4 vs 70 ± 9, p = 0.025). Multifactorial Cox analysis showed that diabetes mellitus, left atrial diameter >45 mm, ventricular rate >110 beats/min, and postoperative AADs were independent risk factors for ER in patients with PAF. The incidence of sinus bradycardia in the observation group was significantly higher than that in the control group (18% vs 3.6%, p = 0.029), but there was no statistical difference in the overall incidence of AADs-related adverse reactions between groups. Compared with dronedarone alone, dronedarone combined with metoprolol sustained-release tablets can significantly reduce ER after RFCA in patients with PAF and improve cardiac function and QoL, without increasing the AADs-related adverse reactions.

Effect of Dronedarone in the Treatment of Atrial Fibrillation in the Asian Population: Post Hoc Analysis of the ATHENA Trial.

PURPOSE: Limited data are available on the impact of dronedarone treatment in Asian patients with atrial fibrillation (AF) or atrial flutter (AFL). This post hoc analysis evaluated the efficacy and safety of dronedarone compared with placebo in populations from Asian and non-Asian regions randomized in the ATHENA trial (A Placebo-Controlled, Double-blind, Parallel Arm Trial to Assess the Efficacy of Dronedarone 400 mg BID for the Prevention of CV Hospitalization or Death From Any Cause in Patients With AF/AFL). METHODS: Time to first hospitalization for cardiovascular events or death from any cause (primary outcome) and time to first AF/AFL event recurrence (secondary outcome) were analyzed by Kaplan-Meier curves and Cox proportional hazards regression. FINDINGS: The risk of experiencing the primary composite outcome was significantly lower in the dronedarone-treated patients in both the Asian (hazard ratio = 0.541; 95% CI, 0.320-0.914]) and non-Asian (hazard ratio = 0.768; 95% CI, 0.696-0.848) populations than in the placebo-treated patients. The median time to the first AF/AFL event recurrence was longer in the dronedarone-treated population than in the placebo-treated populations: 183 vs 92 days (P = 0.165) in the Asian population and 534 vs 196 days (P < 0.001) in the non-Asian population. Treatment-emergent adverse events in Asian (81.2% vs 78.4%) and non-Asian (71.4% vs 68.7%) populations and serious treatment-emergent adverse events in Asian (14.3% vs 15.7%) and non-Asian (20.3% vs 21.5%) patients were comparable in patients taking dronedarone compared with those taking placebo. IMPLICATION: Efficacy and tolerability of dronedarone were consistent in the Asian population compared with the non-Asian population in the ATHENA trial. These finding may aid Asian health care professionals to select the appropriate first-line treatment for Asian patients with AF/AFL.

Predicting drug-drug interactions with physiologically based pharmacokinetic/pharmacodynamic modelling and optimal dosing of apixaban and rivaroxaban with dronedarone co-administration.

BACKGROUND: The concurrent administration of dronedarone and oral anti-coagulants is common because both are used in managing atrial fibrillation (AF). Dronedarone is a moderate inhibitor of the cytochrome P450 3A4 (CYP3A4) enzyme and P-glycoprotein (P-gp). Apixaban and rivaroxaban are P-gp and CYP3A4 substrates. This study aims to investigate the impact of exposure and bleeding risk of apixaban or rivaroxaban when co-administered with dronedarone using physiologically based pharmacokinetic/pharmacodynamic analysis. METHODS: Modeling and simulation were conducted using Simcyp® Simulator. The parameters required for dronedarone modeling were collected from the literature. The developed dronedarone physiologically based pharmacokinetic (PBPK) model was verified using reported drug-drug interactions (DDIs) between dronedarone and CYP3A4 and P-gp substrates. The model was applied to evaluate the DDI potential of dronedarone on the exposure of apixaban 5 mg every 12 h or rivaroxaban 20 mg every 24 h in geriatric and renally impaired populations. DDIs precipitating major bleeding risks were assessed using exposure-response analyses derived from literature. RESULTS: The model accurately described the pharmacokinetics of orally administered dronedarone in healthy subjects and accurately predicted DDIs between dronedarone and four CYP3A4 and P-gp substrates with fold errors <1.5. Dronedarone co-administration led to a 1.29 (90 % confidence interval (CI): 1.14-1.50) to 1.31 (90 % CI: 1.12-1.46)-fold increase in the area under concentration-time curve for rivaroxaban and 1.33 (90 % CI: 1.15-1.68) to 1.46 (90 % CI: 1.24-1.92)-fold increase for apixaban. The PD model indicated that dronedarone co-administration might potentiate the mean major bleeding risk of apixaban with a 1.45 to 1.95-fold increase. However, the mean major bleeding risk of rivaroxaban was increased by <1.5-fold in patients with normal or impaired renal function. CONCLUSIONS: Dronedarone co-administration increased the exposure of rivaroxaban and apixaban and might potentiate major bleeding risks. Reduced apixaban and rivaroxaban dosing regimens are recommended when dronedarone is co-administered to patients with AF.

Clove Oil Endorsed Transdermal Flux of Dronedarone Hydrochloride Loaded Bilosomal Nanogel: Factorial Design, In vitro Evaluation and Ex vivo Permeation.

The goal of this study was to develop a bilosomal gel formulation to enhance transdermal permeability of dronedarone hyrdrochloride (DRN) which suffers from poor oral absorption and limited bioavailability. To overcome this obstacle, bilosomes were successfully prepared using 23 full-factorial design. Span®40, cholesterol, sodium deoxycholate (bile salt), clove oil (permeability enhancer), and either Tween® 60 or Tween® 80 (edge activator) were used in bilosome preparation by ethanol injection method. In this design, independent variables were X1, edge activator type; X2, edge activator amount (mg); and X3, permeability enhancer concentration (% w/v). Optimal formula (B2) of the highest desirability of (0.776) demonstrated minimum vesicle size (VS) of 312.4 ± 24.42 nm, maximum absolute value of zeta potential (ZP) - 36.17 ± 2.57 mV, maximum entrapment efficiency (EE %) of 80.95 ± 3.01%, maximum deformability Index (DI) of 8.24 ± 1.26 g and maximum drug flux after 12 h (J12) of 21.23 ± 1.54 µg/cm2 h upon ex vivo permeation study. After 12 h, 70.29 ± 6.46% of DRN was released from B2. TEM identification of B2 showed spherical shaped nanosized vesicles which were physically stable for 3 months at different temperatures. B2 was incorporated into carboxymethylcellulose gel base for easiness of dermal application. B2 gel demonstrated good physical properties, non-Newtonian psuedoplastic flow, and enhanced release (57.0 ± 8.68% of DRN compared to only 13.3 ± 1.2% released from drug suspension after 12 h) and enhanced skin permeation.

Functional Analysis of Wild-Type and 27 CYP3A4 Variants on Dronedarone Metabolism In vitro.

BACKGROUND: Cytochrome P450 (P450) is the largest family of enzymatic proteins in the human liver, and its features have been studied in physiology, medicine, biotechnology, and phytoremediation. OBJECTIVE: The aim of this study was to assess the catalytic activities of 28 human CYP3A4 alleles by using dronedarone as a probe drug in vitro, including 7 novel alleles recently found in the Han Chinese population. METHODS: We expressed 28 CYP3A4 alleles in insect microsomes and incubated them with 1-100 µM of dronedarone at 37 °C for 40 minutes to obtain the metabolites of N-debutyl-dronedarone. RESULTS: Compared with the wild type of CYP3A4, the 27 defective alleles can be classified into four categories. Three alleles had no detectable enzyme activity leading to a lack of kinetic parameters of N-debutyl-dronedarone; the other three alleles slightly despaired when it comes to intrinsic clearance values compared with the features of the wild type. Sixteen alleles exhibited 35.91%~79.70% relative values (in comparison to the wild-type) and could be defined as the "moderate decrease group". The rest of the alleles showed a considerable decrease in intrinsic clearance values, ranging from 11.88%~23.34%. Therefore they were classified as a "significantly decreased group". More specifically, 18 CYP3A4 alleles exhibited a substrate inhibition trend toward dronedarone when the concentration rises to 20 µM. CONCLUSION: The outcomes of this novel study on the metabolism of dronedarone by CYP3A4 alleles can be used as experimental data support for the individualized use of this modern drug.

Impact of dronedarone on patients with atrial fibrillation and diabetes: A sub-analysis of the ATHENA and EURIDIS/ADONIS studies.

AIM: This post hoc analysis evaluated efficacy and safety of dronedarone in atrial fibrillation (AF) and atrial flutter (AFL) patients with/without diabetes. METHODS: Patients were categorized according to baseline diabetes status. Time-to-event analyses were performed using Kaplan-Meier method. Hazard-ratios were assessed using Cox models. RESULTS: 945/4628 (dronedarone = 482; placebo = 463) patients in ATHENA and 215/1237 (dronedarone = 148; placebo = 67) patients in EURIDIS/ADONIS studies had diabetes. In ATHENA, there were higher rates of CV hospitalization/death in patients with diabetes (39.5%) than without diabetes (34.7%). Incidence of first CV hospitalization/death was lower in patients with diabetes treated with dronedarone (35.1%) than placebo (44.1%), and time to this event was longer in those treated with dronedarone than placebo (log-rank p = 0.005). Median AF/AFL recurrence time was longer in patients treated with dronedarone than placebo in patients with diabetes (ATHENA: 722 vs 527 days, log-rank p = 0.004; EURIDIS/ADONIS: 100 vs 23 days, log-rank p = 0.15) or without diabetes (ATHENA: 741 vs 492 days, log-rank p < 0.0001; EURIDIS/ADONIS: 120 vs 59 days, log-rank p = 0.0002). Occurrence of any treatment-related adverse events with dronedarone was similar for patients with/without diabetes and was comparable to placebo. CONCLUSIONS: Dronedarone reduced incidence of CV hospitalization/death, AF/AFL recurrence and increased time to these events in AF/AFL patients with/without diabetes. TRIAL REGISTRATION: Not applicable, as it was a post hoc analysis. This article is based on previously conducted studies (ATHENA: NCT00174785, EURIDIS: NCT00259428, and ADONIS: NCT00259376).