New Generation of Anticoagulant Drugs In Cardiovascular Diseases
Athanasios J. Manolis
Director of Cardiology Dept, Asklepeion General Hospital, Athens Greece.
Congress set aside $ 1.1 billion last year for head-to-head testing of drugs and treatment to determine which work best and for which type of patient
AF is the Most Common Cardiac Arrhythmia AF affects 1 in 25 adults >60 years1 1 in 10 adults >80 years1 6.8 million patients with AF in EU and US*1,2
EU
4.5 million
US
2.3 million 0
1
2
3
4
5
* EU 2001, US 2006, both cited in 2006 guidelines 1. Go AS et al. JAMA 2001;285:2370-2375 2. Fuster V et al. J Am Coll Cardiol 2006;38:1231-1265
Risk Factor for the Development of AF
Age adjusted odds ratio
38-year follow-up of the Framingham study 4 3 2 1 0
Cigarettes
Diabetes ECG LVH Hypertension
Risk factors
BMI
Alcohol
AF Increases Risk Along the Cardiovascular Continuum
Remodelling
Ventricular dilation
MI
Heart failure
Atherosclerosis and LVH
Risk factors (diabetes, hypertension)
Atrial Fibrillation1,2
End-stage microvascular and heart disease
Death
LVH = Left Ventricular Hypertrophy; RAAS = Renin-Angiotensin-Aldosterone System. 1. Benjamin EJ et al. JAMA 1994;271:840-844; 2. Krahn AD et al. Am J Med 1995;98:476-484; 3. Nakashima H et al. Circulation 2000;101:2612-2617; 4. Tsai CT et al. Circulation 2004;109:1640-1646
ESH/ESC Guidelines and Search for Subclinical Organ Damage 2003 2003 GLs GLs
LVH (Echo) CA thickening / plaques MA
↑ SCr (> 1.4-1.5 mg/dl) EKG †
Routine
2007 2007 GLs GLs
12/12/12 03.28 p. 11760 M
Recommended
↑ SCr (> 1.4-1.5 mg/dl) ↓ eCrCl / GFR MA EKG †
Search for multiorgan OD OD assessed before and during T
LVH (Echo) Concentric LVH LA enlargement CA thickening / plaques Ankle/Brachial ratio Arterial stiffening (PWV)*
* Depending on availability / also shown by high SBP / low DBP
What is Atrial Fibrillation?
In AF, Control of the Heart Rhythm is Taken Away from the Sinus Node Sinus Rhythm
Atrial Fibrillation
Sinus node
Abnormal electrical pathways Normal electrical pathways
Multiple co-existing wavelets cause rapid and irregular atrial activity (400-600 bpm) Veenhuyzen et al. CMAJ sept 28, 2004;171(7)
The Conclusive Sign of AF is the Absence of P Waves on an ECG On the ECG, rapid oscillations, or fibrillatory waves that vary in amplitude, shape, and timing, replace consistent P waves There is an irregular ventricular response that is rapid when conduction is intact
Sinus Rhythm R
R-R Interval
T
P Q
S
P wave
Atrial Fibrillation
ACC/AHA/ESC 2006 guidelines J Am Coll Cardiol 2006;48:854-906
AF is a Progressive Disease
Relative Importance
AF Duration
Trigger dependent (Initiation)
Substrate dependent (Maintenance)
Paroxysmal Persistent Permanent Khan IA Int J Card. 2003;87:301-302
Over Time AF Causes Atrial Remodelling Contractile remodelling Electrical remodelling -
Shortening of atrial refractory periods Occurs rapidly (within several days) and contributes to the increased stability of AF
Shortened refractory period
-
-
Structural remodelling -
-80 mV
Reduced atrial contractility Sets the stage for thrombus formation May lead to atrial dilation further altering electrophysiologic properties Occurs rapidly
-
Histologic changes Left atrium and left atrial appendage enlargement Decrease in cardiac output Occurs after a period of weeks to months
Van Gelder et al. Europace 2006;8:943-949
Cardiac Output Decreases and the Risk of Thromboembolism Increases
Atrial stasis
Loss of atrial contraction (atrial systole)
Loss of atrial systole compromises ventricular filling Ventricle only ejects its contents
Rapid and irregular ventricular rate
Coronary flow is diastolic Diastole shortens due to tachycardia
Risk of thromboembolism Mainly in the left atrial appendage Decrease in ventricular filling: about 20% Decrease in cardiac output
Oxygen consumption increases Supply decreases
ACC/AHA/ESC 2006 guidelines J Am Coll Cardiol 2006;48:854-906
What are the consequences of AF?
AF is an Independent Risk Factor for Stroke AF patients have a near 5-fold increased risk of stroke1 1 in every 6 strokes occurs in a patient with AF2 Ischemic stroke associated with AF is typically more severe than stroke due to other etiologies3 Stroke risk persists even in asymptomatic AF4 1. Wolf et al. Stroke 1991;22:983-988 2. Fuster V et al. Circulation 2006;114:e257-e354 3. Dulli DA et al. Neuroepidemiology 2003;22:118-123 4. Page RL et al. Circulation 2003;107:1141-1145
AF Increases the Risk of Stroke Recurrence and Post-Stroke Mortality Framingham
1-year stroke recurrence
AF patients
Non-AF patients
23%
8%
p<0.001
30-day post stroke mortality
25%
14%
OR 1.84 (95% CI, 1.04 to 3.27)
1-year post stroke mortality
63%
34%
p<0.001
Lin HJ et al. Stroke 1996;27:1760-1764
What are the current treatment strategies for AF?
Atrial fibrillation is easy to find, but evidence on how best to treat it isn’t
Current Treatment Strategies for AF Prevention of thrombo-embolism
Rate control Rhythm control
ACC/AHA/ESC 2006 guidelines J Am Coll Cardiol 2006;48:854-906
Effect of hypertension on anticoagulated patients with atrial fibrillation Rates of stroke/SEE rate in SPORTIF III and V by quartiles of individual patient mean SBP values (84.0-122.6, 122.7-131.3, 131.4-140.7, and 140.8-191.7mmHg)
Event rate (%PY)
3 2.52 2.26 2
1.77
1.52
1.47
1.47 1.06
1.06 1
0
SPORTIF III-V Ximelagatran Q1Q2Q3Q4
Warfarin Q1Q2Q3Q4 Lip G. et al., Eur Heart J 2007
AF Increases Risk Along the Cardiovascular Continuum
Remodelling
Ventricular dilation
MI
Heart failure
Atherosclerosis and LVH
Risk factors (diabetes, hypertension)
Atrial Fibrillation1,2
End-stage microvascular and heart disease
Death
RAAS can impact the progression of AF and inhibition of RAAS can have some beneficial effects3,4 LVH = Left Ventricular Hypertrophy; RAAS = Renin-Angiotensin-Aldosterone System. 1. Benjamin EJ et al. JAMA 1994;271:840-844; 2. Krahn AD et al. Am J Med 1995;98:476-484; 3. Nakashima H et al. Circulation 2000;101:2612-2617; 4. Tsai CT et al. Circulation 2004;109:1640-1646
Meta-analysis: Inhibition of renin-angiotensin system prevents new-onset atrial fibrillation 95% CI
RR
Lower Limit
Upper Limit
% Weight
CAPPP
0.87
0.68
1.11
23.6
STOP-2
1.12
0.95
1.32
26.4
LIFE
0.66
0.54
0.81
25.2
VALUE
1.20
0.97
1.48
24.8
Pooled RR
0.94
0.72
1.23
GISSI-3
0.92
0.83
1.01
60
TRACE
0.52
0.31
0.87
40
Pooled RR
0.73
0.43
1.26
Val-HeFT
0.67
0.54
0.83
38.7
SOLVD
0.22
0.12
0.43
21.9
CHARM
0.82
0.68
1.00
39.4
Pooled RR
0.57
0.37
0.89
Hypertension trials
Post-myocardial infarction trials
Heart failure trials
Kishlay A. et al., Am. Hear J 2006; 152:217-22.
How Did RAS Blockers Reduce the Risk of Stroke “Beyond Blood Pressure”? Cardiac remodeling/ enlargement
Reduced ECG–LVH
Vascular remodeling
Inhibited atherosclerosis formation Reduced carotid artery hypertrophy Reduced gluteal artery hypertrophy
Endothelial dysfunction
Improved endothelial function
Prothrombotic state
Inhibition of platelet aggregation Reduced proaggregatory factors
Anti-thrombotic Therapy is Essential for Reducing Risk of Stroke Current clinical practice recommends that anticoagulation should be continued for life in patients at high risk of thrombo-embolism or with risk factors for atrial fibrillation recurrence The CHADS2 (Cardiac Failure, Hypertension, Age, Diabetes, Stroke [Doubled]) is a points based system for predicting risk of stroke in AF, based on key risk factors and serves as a guideline for anticoagulation treatment Prior stroke or TIA Age >75 years Hypertension Diabetes mellitus
2 points 1 point 1 point 1 point
CHADS2 Stroke Risk Stratification Scheme For Patients With Nonvalvular AF Risk Factors
Score
C
Recent congestive heart failure
1
H
Hypertension
1
A
Age ≥ 75 y
1
D
Diabetes mellitus
1
S2
History of stroke or transient ischemic attack
2
Stroke Rate %
20
18.2
15
12.5
10 5
1.9
2.8
4.0
5.9
2
3
Relationship between CHADS2 score and annual risk of stroke
8.5
0 0
1
4
CHADS2 Score
5
6
Stroke Risk Assessment in AF: CHA2DS2-VASC* Stroke Risk Factors
Score
Congestive heart failure / LV dysfunction
1
Hypertension
1
Age ≥75 yrs
2
Diabetes mellitus
1
Stroke / TIA / TE
2
Vascular disease
1
(prior MI, PAD, or aortic plaque) Age 65-74
1
Sex category (i.e., female sex)
1
AF-related stroke is preventable 2/3 of strokes due to AF are preventable with appropriate anticoagulant therapy with a vitamin-K-antagonist (INR 2-3)1 Anticoagulation with a vitaminK-antagonist (VKA) is recommended for patients with more than 1 moderate risk factor (age,HBP, CHF or LVD, Diabetes)
Effect of VKA compared to placebo Stroke
Death
67%
26%
A meta-analysis of 29 trials in 28,044 patients showed that adjusted-dose warfarin results in a reduction in ischaemic stroke and in all-cause mortality 1 1. Hart RG et al. Ann Intern Med. 2007;146:857-867 2. Fuster V, et al. JACC. 2006; 48: 854-
Oral VKAs Advantages of warfarin
Disadvantages of warfarin
Used for more than 60 years
Requires frequent monitoring to keep in therapeutic range
Well studied Fairly effective if INR kept in therapeutic range Well-known and defined drug and food interactions
Multiple medication adjustments often required Significant interactions with multiple medications and foods Patient reluctance
Relatively inexpensive Easy to reverse
Bad reputation among healthcare providers
Underuse of oral anticoagulants in AF: A Systematic Review Underuse of oral anticoagulants for high-risk atrial fibrillation patients was found in most of the 54 studies (19982008) reporting both patient stroke risk and patients treated. Over two thirds of studies of atrial fibrillation patients with prior stroke or transient ischemic attack reported treatment levels of under 60% of eligible patients. Most studies based on CHADS2 score reported oral anticoagulant treatment levels of high-risk subjects below 70%.
Ogilvie I et al Am J Med 2010;123:638
Key features of a “new contender” in the prevention of CV events in AF
Freedom from coagulation monitoring Simpler kinetic profile More rapid onset and offset Reduced or absent drug-drug and drug-food interactions More “user-friendly” than Warfarin
Alternative to warfarin in patients with AF Treatment Clopidogrel+ASA
Limitations > Effective vs. ASA alone but <
Warfarin (ACTIVE-W study)
Idraparinux s.c. once weekly
> Effective vs. Warfarin but >> risk of bleeding (AMADEUS Study)
Oral Ximelagatran
= Warfarin for efficacy and safety but hepatotoxicity (SPORTIF Studies)
Targets of different antithrombotic drugs Indirect inhibition
Direct inhibition (block the face of coagulation propagation)
Fondaparinux Idraparinux AT III
-
Xa
-
-
Enoxaparin
Apixaban Rivaroxaban Otapixaban Edoxaban
AT III UFH AT III
-
II III
Thrombin inhibitors (prevent fibrin formation and block throbin mediiated activation of other anticoagulant factors)
-
Bivalirudin Dabigatran
Atrial Fibrillation Phase 3 Study Timelines Dabigatran
Rivaroxaban
Edoxaban
RE-LY RELYABLE
ROCKET AHA 11/10
ENGAGE-AF TIMI 48
2009
2010
2011
AVERROES estimated completion April 2010
ARISTOTLE Estimated completion November 2010
Apixaban .
Antithrombotic Prophylaxis in AF NEW PERSPECTIVES Oral Factor Xa inhibitors Parenteral Factor Xa inhibitors (modified idraparinux) New oral direct thrombin inhibitors (other than ximelagatran)
New Oral Direct FXa Inhibitors Under Investigation for Stroke Prevention in Atrial Fibrillation
Rivaroxaban
Bayer
Phase III
Apixaban
Bristol-Myers Squibb
Phase III
Edoxaban
Daiichi Sankyo
Phase III
YM 150
Astellas Pharma
Planned
LY 517717
Lilly
Planned
PRT 054021
Portola
Planned
ROCKET AF Trial Atrial Fibrillation
Rivaroxaban
Randomize Double blind / Double Dummy (n ~ 14,000)
Risk Factors • CHF At least 2 • Hypertension required • Age ≥ 75 • Diabetes OR • Stroke, TIA, or Systemic embolus
Warfarin
INR target - 2.5 (2.0-3.0 inclusive)
20 mg daily 15 mg for Cr Cl 30-49
Monthly monitoring and adherence to standard of care guidelines
Primary Endpoint: Stroke or non-CNS systemic embolism Statistics: non-inferiority, >95% power, 2.3% warfarin event rate
Primary Efficacy Outcome Stroke and non-CNS Embolism Cumulative event rate (%)
6 5
Rivaroxaban
Warfarin
1.71
2.16
Event Rate
Warfarin
4
Rivaroxaban
3
HR (95% CI): 0.79 (0.66, 0.96)
2
P-value Non-Inferiority: <0.001
1 0
0
No. at risk: Rivaroxaban 6958 Warfarin 7004
120
240
360
480
600
720
840
Days from Randomization 6211 6327
5786 5911
5468 5542
4406 4461
Event Rates are per 100 patient-years Based on Protocol Compliant on Treatment Population
3407 3478
2472 2539
1496 1538
634 655
960
Primary Efficacy Outcome
Stroke and non-CNS Embolism Rivaroxaban
Warfarin
Event Rate
Event Rate
HR (95% CI)
P-value
On Treatment
1.70
2.15
0.79 (0.65,0.95)
0.015
ITT
2.12
2.42
0.88 (0.74,1.03)
0.117
N= 14,143
N= 14,171
Rivaroxaban better
Warfarin better
Event Rates are per 100 patient-years Based on Safety on Treatment or Intention-to-Treat thru Site Notification populations
Key Secondary Efficacy Outcomes Rivaroxaban
Warfarin
Event Rate
Event Rate
HR (95% CI)
P-value
Vascular Death, Stroke, Embolism
3.11
3.63
0.86 (0.74, 0.99)
0.034
Stroke Type Hemorrhagic Ischemic Unknown Type
0.26 1.34 0.06
0.44 1.42 0.10
0.59 (0.37, 0.93) 0.94 (0.75, 1.17) 0.65 (0.25, 1.67)
0.024 0.581 0.366
Non-CNS Embolism
0.04
0.19
0.23 (0.09, 0.61)
0.003
Myocardial Infarction
0.91
1.12
0.81 (0.63, 1.06)
0.121
All Cause Mortality Vascular Non-vascular Unknown Cause
1.87 1.53 0.19 0.15
2.21 1.71 0.30 0.20
0.85 (0.70, 1.02) 0.89 (0.73, 1.10) 0.63 (0.36, 1.08) 0.75 (0.40, 1.41)
0.073 0.289 0.094 0.370
Event Rates are per 100 patient-years Based on Safety on Treatment Population
Primary Safety Outcomes Rivaroxaban
Warfarin
Event Rate or N (Rate)
Event Rate or N (Rate)
HR (95% CI)
P-value
3.60 2.77 1.65 0.82 0.24
3.45 2.26 1.32 1.18 0.48
1.04 (0.90, 1.20) 1.22 (1.03, 1.44) 1.25 (1.01, 1.55) 0.69 (0.53, 0.91) 0.50 (0.31, 0.79)
0.576 0.019 0.044 0.007 0.003
55 (0.49)
84 (0.74)
0.67 (0.47, 0.94)
0.019
Intraparenchymal
37 (0.33)
56 (0.49)
0.67 (0.44, 1.02)
0.060
Intraventricular
2 (0.02)
4 (0.04)
Subdural
14 (0.13)
27 (0.27)
0.53 (0.28, 1.00)
0.051
Subarachnoid
4 (0.04)
1 (0.01)
Major >2 g/dL Hgb drop Transfusion (> 2 units) Critical organ bleeding Bleeding causing death Intracranial Hemorrhage
Event Rates are per 100 patient-years Based on Safety on Treatment Population
Summary Efficacy: Rivaroxaban was non-inferior to warfarin for prevention of stroke and non-CNS embolism. Rivaroxaban was superior to warfarin while patients were taking study drug. By intention-to-treat, rivaroxaban was non-inferior to warfarin but did not achieve superiority. Safety: Similar rates of bleeding and adverse events. Less ICH and fatal bleeding with rivaroxaban. Conclusion: Rivaroxaban is a proven alternative to warfarin for moderate or high risk patients with AF.
APIXABAN Phase 3 Clinical Trial vs Warfarin to Prevent Stroke or Embolism in AF Pts ARISTOTLE ≈ 1.8 years
Patient characteristics
• Atrial fibrillation ∀≥1 additional risk factor for stroke
Apixaban 2.5 mg bid or 5 mg bid
N=15,000
noi t azi mo dna R
• Aged ≥18 years
Warfarin 2 mg qd, target INR 2.0-3.0
Primary outcome measures: Time to first occurrence of confirmed stroke or systemic embolism Time to major bleeding in treatment or follow-up AF = atrial fibrillation; INR = international normalized ratio. National Institutes of Health Clinical Trials.gov. www.clinicaltrials.gov/ct2/show/NCT00412984?term=apixaban&rank=4. Accessed January 16, 2008.
ENGAGE-AF-TIMI 48 (Study for Evaluation of DU-176b (Edoxaban) vs Warfarin in Subjects with AF)
n~16,500
AF on ECG < 12 mos Intended oral A/C CHADS2 Score > 2
R Low Exposure Strategy DU-176b 30 mg QD (n=5500)
Randomization Strata: 1. CHADS2 2-3 vs 4-6 2. Drug clearance
High Exposure Strategy DU-176b 60 mg QD (n=5500)
Median Duration of Followup 24 months 1º EP = Stroke or SEE (Noninferiority Boundary HR 1.38) 2º EP = Stroke or SEE or All-Cause Mortality Safety EP’s = Major Bleeding, Hepatic Function
Active Control Warfarin (n=5500)
BOREALIS-AF: Trial design Double-blind Ongoing
R
# CHADS2 ≥ 2
Idrabiotaparinux Subcutaneous, 3 mg once weekly for 7 weeks, then adjusted based on age and renal function
Primary outcome measures
Efficacy: all stroke and systemic embolism
Safety: clinically relevant bleeding
3-6 months observational period
Patients with atrial fibrillation + an indication for anticoagulation
Warfarin (INR 2.0–3.0)
Anti-Thrombotic Prophylaxis in AF NEW PERSPECTIVES Oral Factor Xa inhibitors Parenteral Factor Xa inhibitors (modified idraparinux) New oral direct thrombin inhibitors (other than ximelagatran)
RE-LY® – study design Atrial fibrillation with ≥ 1 risk factor Absence of contraindications
R Warfarin 1 mg, 3 mg, 5 mg (INR 2.0-3.0) N=6000
Dabigatran etexilate 110 mg bid N=6000
Dabigatran etexilate 150 mg bid N=6000
Primary objective: To establish the non-inferiority of dabigatran etexilate to warfarin Minimum 1 year follow-up, maximum of 3 years and mean of 2 years of follow-up Ezekowitz MD, et al. Am Heart J 2009;157:805-10. Connolly SJ., et al. NEJM published online on Aug 30th 2009. DOI 10.1056/NEJMoa0905561
RE-LY® – outcome measures Primary efficacy endpoint
Secondary efficacy endpoints
All stroke (ischaemic + haemorrhagic) and systemic embolism
All stroke (ischaemic + haemorrhagic) Systemic embolism All death Pulmonary embolism Acute MI Vascular death (incl. deaths from bleeding)
Safety criteria include Bleeding events (major and minor) Intracranial haemorrhage Cerebral haemorrhage Subdural haematoma Subarachnoid haemorrhage Elevations in liver enzymes or hepatic dysfunction
Connolly SJ., et al. NEJM published online on Aug 30th 2009. DOI 10.1056/NEJMoa0905561
RE-LY Study: Time to first stroke / SSE RR 0.91 (95% CI: 0.74–1.11) p<0.001 (NI) p=0.34 (Sup)
Cumulative hazard rates
0.05 0.04
RRR 34%
Warfarin Dabigatran etexilate 110 mg Dabigatran etexilate 150 mg
0.03
RR 0.66 (95% CI: 0.53–0.82) p<0.001 (NI) p<0.001 (Sup)
0.02
0.01
0.00 0
0.5
1.0
1.5
2.0
2.5
Years RR, relative risk; CI, confidence interval; NI, non-inferior; Sup, superior Connolly SJ., et al. NEJM published online on Aug 30th 2009. DOI 10.1056/NEJMoa0905561
RE-LY Study: Hemorrhagic stroke RR 0.31 (95% CI: 0.17–0.56) p<0.001 (sup)
50
RR 0.26 (95% CI: 0.14–0.49) p<0.001 (sup)
45
40
RRR 74%
RRR 69%
0.38%
30
st nev ef o r eb mu N
20 10
14
12
0.12%
0.10%
0 D110 mg BID
D150 mg BID
Warfarin
6,015
6,076
6,022
RE-LY® – summary results 110 mg dose versus warfarin Comparable rates of stroke/systemic embolism Statistically significant reduction in hemorrhagic stroke Statistically significant reduction in major bleeding rates Significant reduction in total bleeds, life threatening bleeds and intracranial bleeds 150 mg dose v. warfarin Statistically significant reduction in stroke/systemic embolism Statistically significant reduction in hemorrhagic stroke Statistically significant reduction in vascular mortality Comparable rates of major bleeding rates Significant reduction in total bleeds, life threatening bleeds and intracranial bleeds
Connolly SJ., et al. NEJM published online on Aug 30th 2009. DOI 10.1056/NEJMoa0905561
Bleeding Risk Assessment in AF: HAS-BLED Bleeding Risk Score Letter
Clinical Characteristic*
Points Awarded
H
Hypertension
1
A
Abnormal renal and liver function (1 point each )
S
Stroke
1
B
Bleeding
1
L
Labile INRS
1
E
Elderly
1
D
Drugs or alcohol
1 or 2
1 or 2 Maximum 9 points
Ideal candidates for the use of Dabigatran among patients with AF
Warfarin-naïve Hard to maintain the therapeutic range Previous bleeding complication with Warfarin Multiple medications (high risk of interactions)
Open issues in the RE-LY study Short follow-up (safety requires longer observations) Small but significant excess of MI in high dose of Dabigatran vs. Warfarin The risk/benefit of combining Warfarin with antiplatelet agents (only 20% of study patients) Safety and efficacy in patients with renal failure (<30 ml/min excluded from study) No known antidote or reversal agent for Dabigatran
Dabigatran: FDA approval
FDA advisory panel in September voted 9-0 to recommend that dabigatran be approved FDA approved October 20,2010 Doses approved: 150 mg twice daily 75 mg twice daily (severe renal impairment)
Canadian Cardiovascular Guidelines for AF Based on its safety and efficacy profile, dabigatran is preferred over warfarin. Overall, the 150 mg dose of dabigatran is preferred over the 110 mg dose. For patients at low risk of stroke (CHADS2 score=1), treatment should include either warfarin or dabigatran. However, based on individual risk/benefit considerations, aspirin is a resonable alternative. For patients at moderate to high risk of stroke (CHADS2 >2), treatment should include either warfarin or dabigatran October 26,2010
How can we make a strong recommendation from one trial?
That single trial includes more patients than all the trials with warfarin combined (18.000 patients)
Comprehensive Management of AF Should Address its Multiple Impacts In addition to stroke prevention and reduction of AF burden*, successful management of AF should also aim at further reducing hospitalisations as well as CV morbidity and mortality
Prevention of thromboembolism
Reduction of AF burden* ↑ QoL ↓ Symptoms
Reduction in the risk of CV events and hospitalisations
Reduction in mortality
Current Treatment Strategies for AF
Prevention of thromboembolism
Rate control Rhythm control
The Aim of Rhythm Control is to Restore Sinus Rhythm and Maintain it
Restore sinus rhythm
Maintain sinus rhythm
Anti-arrhythmic drugs (AADs) Electrical cardioversion
Successful rhythm control has physiological advantages over rate control: Produces better control of symptoms than rate control Can also improve left ventricular function and exercise capacity, even compared to AF patients with controlled ventricular rate Lip et al. Lancet 2007;370:604 -18
Structural Differences Between Dronedarone and Amiodarone
Zimetbaum PJ, et al. N Engl J Med 2009;360(18):1811-13.
Dronedarone
Amiodarone
Bioavailability
Increased to 15% with food
50%
Volume of Distribution
~12L/kg
~60L/kg
Protein Binding
>98%
~96%
Metabolism
Primarily CYP3A4
CYP3A4 and CYP2D6
Elimination half life
~13-19h
~58 days
Excretion
Feces: 84% Renal: 6%
Hepatically
Dose Adjustment in Renal Impairment?
None
None
Dose Adjustment in Hepatic Impairment?
Moderate: None Limited data. Severe: Contraindicated Monitoring recommended
Schafer JA, et al. Cardiovasc Ther 2010
Dronedarone has Multiple Properties Extensive anti-arrhythmic efficacy at atrial and ventricular level1, 2 Rate controlling effects1 Vasodilatory effects2 Anti-adrenergic effects3 Blood pressure lowering properties4 1 Gautier P, et al. J Cardiovasc Pharmacol. 2003;41(2):191-202. 2 Hodeige D, et al. European Journal of Pharmacology 1995;279:25-32. 3 Guiraudou P, et al. European Journal of Pharmacology 2004;496:119-127. 4 Hohnloser SH et al. N Engl J Med 2009;360:668-78.
Dronedarone – Warnings
• Dronedarone increases serum creatinine levels ~0.1 mg/dl increase Inhibits tubular secretion of creatinine No effect on GFR Rapid onset, plateaus after 7 days, reversible upon drug discontinuation
Multaq [package insert]. Bridgewater, NJ: Sanofi Aventis; 2009
DAFNE Dronedarone 400mg bid Significantly Prolonged Time to First AF Recurrence
Proportion of patients in sinus rhythm
Patients with persistent AF were randomly allocated to 800, 1200, 1600 mg daily doses of dronedarone or placebo. The main analysis was conducted on 199/270 patients, who entered the maintenance phase following pharmacological cardioversion or, if unsuccessful, DC cardioversion. 1.0 Placebo DR 800mg DR 1200mg DR 1600mg
0.9 0.8 0.7
55% RRR 800mg vs placebo (p=0.001)
0.6 0.5 0.4 0.3 0.2 0.1 0.0 0
30
60
90
120
150
180
Days
Touboul P, et al. Eur Heart J. 2003;24:1481-7 .
EURIDIS and ADONIS Objective EURIDIS and ADONIS investigated whether dronedarone is superior to placebo on top of standard therapy* for maintaining sinus rhythm after electrical, pharmacologic, or spontaneous conversion from atrial fibrillation or atrial flutter
* Standard therapy may have included rate control agents (beta-blockers, and/or Ca-antagonists and/or digoxin) and/or antithrombotic therapy (oral anticoagulation and/or long-term antiplatelet therapy) and/or other cardiovascular therapy such as ACE inhibitors and statins
Singh BN, et al. N Engl J Med. 2007;357:987-99.
Dronedarone for Maintenance of Sinus Rhythm in Atrial Fibrillation or Flutter 828 patients at least 21 years of age with at least one episode of atrial fibrillation in the preceding 3 months, in sinus rhythm for at least 1 hour before randomization. receiving dronedarone 400 mg twice daily and 409 receiving placebo FU 12 months
Hohnloser, M.D., for the EURIDIS and ADONIS Investigators, NEJM 2007
ANDROMEDA 1000 patients who were hospitalized with symptomatic heart failure and severe LV systolic dysfunction randomized to receive 400 mg of dronedarone twice a day or placebo. The primary end point was the composite of death from any cause or hospitalization for heart failure
HR in the dronedarone group, 1.38; 95% CI, 0.92 to 2.09; p = 0.12
HR in the dronedarone group, 2.13; 95% CI, 1.07 to 4.25; p = 0.03
Conclusions: In patients with severe heart failure and left ventricular systolic dysfunction, treatment with dronedarone was associated with increased early mortality related to the worsening of heart failure. N Engl J Med 2008
ATHENA-Results 40
p<0.001 p<0.001
%
Dronedarone
30
Placebo p<0.001
20
10 p=0.18 p=0.03 p=0.01
0 Primary endpoint
First hospitalization for CV causes
First hospitalization for AF
Death from any cause
Death from CV causes
Death from cardiac arrhythmias
Hohnloser et al for the ATHENA Investigators, N Engl J Med 2009
Analysis of Stroke in ATHENA: A Placebo-Controlled Double-Blind, Parallel-Arm Trial to Assess the Efficacy of Dronedarone 400 mg BID for the Prevention of Cardiovascular Hospitalization or Death From Any Cause in Patients With Atrial Fibrillation / Atrial Flutter
“Conclusions—In this post hoc analysis, a reduction in stroke was observed in patients with atrial fibrillation who were receiving usual care, which included antithrombotic therapy and heart rate control, who were randomized to dronedarone. Further studies to investigate the effect of dronedarone and other antiarrhythmic agents on stroke are indicated”
Connolly et al, Circulation 2009
A Short-Term, Randomized, Double-Blind, Parallel-Group Study to Evaluate the Efficacy and Safety of Dronedarone versus Amiodarone in Patients with Persistent Atrial Fibrillation:
The DIONYSOS Study Five hundred and four amiodarone-naıve patients were randomized to receive dronedarone 400 mg bid (n = 249) or amiodarone 600 mg qd for 28 days then 200 mg qd (n = 255) for at least 6 months. Primary composite endpoint was recurrence of AF (including unsuccessful electrical cardioversion, no spontaneous conversion and no electrical cardioversion) or premature study discontinuation. Main safety endpoint (MSE) was occurrence of thyroid-, hepatic-, pulmonary-, neurologic-, skin-, eye-, or gastrointestinal-specific events, or premature study drug discontinuation following an adverse event. J Cardiovasc Electrophysiol, Vol. 21, pp. 597-605, June 2010
DIONYSOS-RESULTS Amiodarone 80.0% 70.0% 60.0% 50.0% 40.0% 30.0% 20.0% 10.0% 0.0%
Dronedarone
* 73.9% 63.5% 55.3% 42.0%
13.3%
Composite 1 Endpoint
o
First Recurrence
10.4%
Premature Drug D/C
§ Primary composite endpoint: Time to first AF Recurrence or Premature Drug Discontinuation at 12 months
J Cardiovasc Electrophysiol, Vol. 21, pp. 597-605, June 2010
ADVERSE EVENT Adverse Event
Dronedarone
Amiodarone
P Value
Primary Safety Endpoint GI
33.9%
44.5%
p=0.13
13.3%
7.1%
Thyroid
1.2%
7.8%
p<0.001
Neurologic
1.2%
9.4%
p<0.001
Ocular and hepatic events were similar between groups. No cases of pulmonary fibrosis in either group. § Primary Safety Endpoint: First occurrence of a thyroid, hepatic, pulmonary, neurologic, skin, ocular, or GI related event, or any adverse event requiring drug discontinuation “Conclusion: In this short-term study, dronedarone was less effective than amiodarone in decreasing AF recurrence, but had a better safety profile, specifically with regard to thyroid and neurologic events and a lack of interaction with oral anticoagulants.” J Cardiovasc Electrophysiol, Vol. 21, pp. 597-605, June 2010
Comparative Efficacy of Dronedarone and Amiodarone for the Maintenance of Sinus Rhythm in Patients with Atrial Fibrillation - a systematic overview of all randomized controlled trials in which the authors evaluated dronedarone or amiodarone for the prevention of AF. The effect of amiodarone versus dronedarone was summarized by the use of indirect comparison meta-analysis and normal logistic meta-regression models.
Piccini et et al, al, JJ Am Am Coll Piccini Coll Cardiol Cardiol2009 2009
Comparative Efficacy of Dronedarone and Amiodarone for the Maintenance of Sinus Rhythm in Patients with Atrial Fibrillation ”…A normal logistic regression model incorporating all trial evidence found amiodarone superior to dronedarone (OR: 0.49; 95% CI: 0.37 to 0.63; p 0.001) for the prevention of recurrent AF. In contrast, these models also found a trend toward greater all-cause mortality (OR: 1.61; 95% CI: 0.97 to 2.68; p 0.066) and greater overall adverse events requiring drug discontinuation with amiodarone versus dronedarone (OR: 1.81; 95% CI: 1.33 to 2.46; p 0.001).
”Conclusion: Dronedarone is less effective than amiodarone for the maintenance of sinus rhythm, but has fewer adverse effects. For every 1,000 patients treated with dronedarone instead of amiodarone, we estimate approximately 228 more recurrences of AF in exchange for 9.6 fewer deaths and 62 fewer adverse events requiring discontinuation of drug.” Piccini et al, J Am Coll Cardiol 2009
Dronedarone: FDA Approval: July 2009 • Indicated to reduce the risk of CV hospitalization in patients with paroxysmal or persistent atrial fibrillation (AF) or atrial flutter (AFL). Dose: 400mg po BID • Patients: In sinus rhythm or who will be cardioverted Recent episode of AF/AFL CV risk factors Age > 70yrs Hypertension Diabetes Prior CVA Left Atrial Diameter > 55 mm EF < 40%
Potential Role for Amiodarone and Dronedarone in AF
*Dronedarone as a reasonable alternative for patients intolerant of first-line treatment.
Adapted from Singh et al, JACC 2010
Conclusions Dronedarone exhibits both rhythm and rate control properties and has been proven to significantly prolong time to AF recurrence and decrease ventricular rate Dronedarone demonstrates a low risk of pro-arrhythmia, cardiac and extra-cardiac toxicity, with favourable tolerability
However, ANDROMEDA results preclude its use in patients with unstable heart failure, such as patients with Class IV heart failure or recent hospitalization for decompensation of heart failure
Dronedarone is easy-to-use because of its fixed-dosing regimen, outpatient initiation and minimal monitoring requirements Dronedarone is the only anti-arrhythmic drug proven to reduce CV hospitalisation or mortality in AF patients, excluding those with unstable heart failure, whilst also prolonging time to AF recurrence and providing rate control - all achieved with a favourable safety profile
Warfarin, Aspirin, or Both after MI (WARIS) Distribution of Separate Events According to Treatment Group* Event
Aspirin (n=1206)
Warfarin (n=1216)
Aspirin Plus Warfarin (n=1208)
Rate Ratio P Value (95% CI)
No. of events
Reinfarction
117
Thromboembolic stroke
32
17
17
Death
92
96
95
90
69
*CI denotes confidence interval, and NS not significant †The rate ratio is for aspirin plus warfarin as compared with aspirin ‡The rate ratio is for warfarin as compared with aspirin
0.56 (0.41-0.78)†
<.001
0.74 (0.55-0.98)‡
.03
0.52(0.28-0.98)†
.03
0.52(0.28-0.97)‡
.03
.82
A Phase II RE-DEEM Overview Randomized, double-blind, placebo-controlled, dose escalation study ST elevation or non-ST elevation ACS with ≥1 additional risk factor for CV complications, on aspirin & clopidogrel at randomization
Randomization within 14 days
Placebo BID N=373
Dabigatran 50 mg BID N=372
Dabigatran 75 mg BID N=371
Dabigatran 110 mg BID N=411
Dabigatran 150 mg BID N=351
Study treatment for 6 months
Primary outcome: Secondary (efficacy):
Major * + clinically relevant minor bleeds Coagulation activity (D-dimer) Clinical endpoints (death, MI, stroke)
RE-DEEM Primary Outcome - Bleeding ITT= Intention to treat; OT=On treatment (within 3 days before the event) 9
Clinically relevant minor
8
Major (ISTH) P<.001 linear trend N=1861
7
%
6
24
5
23
23
23
6
4
4
O T
ITT
4 3 2
7
1 0
10 7
2 ITT
Placebo
O T
15 9
14 8
3
2
ITT
O T
Dabigatran 50
ITT
OT
Dabigatran 75
ITT
Dabigatran 110
O T
Dabigatran 150
APPRAISE
RE-DEEM
ISTH Major or CR Minor Bleeding Dual Antiplatelet Group
ISTH Major or CR Minor Bleeding Dual Antiplatelet
ATLAS TIMI Major + Minor + Req Medical Attention Dual Antiplatelet Group
12%
10%
8%
6%
4%
2%
0% Placebo
Apixaban 2.5 BID 5 BID
Placebo D50 D75 D110 D150
Placebo
Rivaroxaban 2.5 BID 5 BID
RE-DEEM Clinical Endpoint- Secondary Outcome Composite of CV Death, Nonfatal MI, Stroke 9
Stroke
8
%
7
Nonfatal MI
6
CV death 1
5 4 3 3
2
4
4
9
8
2
1
1 8
9
8
8 7 8
6
9
O T
Placebo
ITT
O T
5 ITT
OT
8
4
4
4
8
0 ITT
8
ITT
2 O T
ITT
O T
Dabigatran 50 Dabigatran 75 Dabigatran 110 Dabigatran 150
Consequences of AF
Hospitalizations: Most common arrhythmia requiring hospitalization 2-3 risk for hospitalization
Mortality: 2x risk independent of comorbid CV disease Sudden death in heart failure and HCM
Thromboembolism: Stroke: 4.5x risk Microemboli: reduced cognitive function Prothrombotic state
Reduced QoL: Palpitations, dyspnea, fatigue, exercise tolerance
Impaired Hemodynamics: Loss of atrial kick Irregular ventricular contractions Heart failure Tachycardia-induced cardiomyopathy
Sinus Rhythm Strategy: Who Are Appropriate Candidates? Highly
symptomatic with AF
First episode Reversible cause Young age Symptomatic despite rate control Rate-related cardiomyopathy LV dysfunction / CHF Diastolic dysfunction with symptoms HCM or aortic stenosis Prior embolic stroke or TIA
New Pharmacologic Agents for AF Multi-ion channel blockers: Dronedarone Budiodarone
Atrial-selective AADs: I Kur -, Ito and I KACh blocker Atrial-selective Na channel blocker Histamine (5-HT4) receptor antagonist
Other ion channel blockers Other mechanisms Upstream therapies: Statins ACEI / ARB Omega -3 fatty acids Anti-inflammatory drugs