Thrombosis and Hemostasis

Transcription

1 Thrombosis and Hemostasis Wendy Lim, MD, MSc, FRCPC Associate Professor, Department of Medicine McMaster University, Hamilton, ON

2 Overview To review the important developments in venous thromboembolism (VTE) in 2013 To highlight the key data in these areas to be presented at ASH To provide a Canadian perspective on these developments and the impact on clinical practice

3 Key News in 2013: New (novel) oral anticoagulants (NOACs) Direct thrombin inhibitors Dabigatran (Pradaxa ) P: 110 mg 1-4 h postop, 220 mg od T: 110 mg or 150 mg bid Direct Factor Xa inhibitors Rivaroxaban (Xarelto ) P: 10 mg od T: 15 mg bid x 3/52, 20 mg od (VTE), 20 mg or 15 mg od (AF) Apixaban (Eliquis ) P: 2.5 mg bid; T: 5 mg bid Edoxaban (Lixiana ) P = prophylaxis in orthopedic surgery; T= treatment dose

4 Standard antithrombotic drug development progress Orthopedic prophylaxis VTE treatment Atrial fibrillation Extended VTE treatment Medical prophylaxis Acute coronary syndromes Mechanical heart valves

5 Dabigatran RE-ALIGN Phase II dose-validation study of 2 groups: #1 AVR or MVR in past 7 days; #2- valve replacement >3 months, randomly assigned 2:1 to dabigatran or warfarin Dabigatran 150, 220 or 300 mg bid (based on renal function), dose adjusted to trough plasma level >50 ng/ml vs. warfarin INR 2-3 or Primary end point trough plasma level of dabigatran Results Premature termination after 252 patients enrolled Excess TE and bleeding in dabigatran group As treated analysis: Dose adjustment/discontinuation of dabigatran in 52/162 (32%) Ischemic stroke in 9/168 (5%) dabigatran vs. 0/84 (0%) in warfarin Major bleeding in 7/168 (4%) vs. 2/84 (2%); all pericardial Eikelboom et al. N Engl J Med 2013;369:

6 Dabigatran for mechanical heart valves The use of dabigatran in patients with mechanical heart valves was associated with increased rates of thromboembolic and bleeding complications, as compared with warfarin, thus showing no benefit and an excess risk Eikelboom et al. N Engl J Med 2013;369:

7 Dabigatran RE-SONATE Two double-blind randomized trials Dabigatran 150 mg bid vs. warfarin (active-control study) Dabigatran 150 mg bid vs. placebo (placebo-control study) ASH 2012 Results Patients completed 6-18 months AC prior to enrolment Active control, dabigatran vs. warfarin Recurrent VTE: 26/1430 (1.8%) vs. 18/1426 (1.3%) HR 1.44, , p=0.01 for noninferiority Major bleeding: 13 (0.9%) vs. 25 (1.8%) HR 0.52, Schulman et al. N Engl J Med 2013;368:709-18

8 Dabigatran Results Completed at least 3 mo AC Placebo control (dabigatran vs. placebo) Recurrent VTE: 3/681 (0.4%) vs. 37/662 (5.6%) HR 0.08, , p<0.001 Major bleeding: 2 (0.3%) vs. 0 Major or clinically relevant bleeding: 36 (5.3%) vs. 12 (1.8%) HR 2.92 ( ) Dabigatran was effective in the extended treatment of VTE and carried a lower risk of major or CRB than warfarin but a higher risk than placebo Schulman et al. N Engl J Med 2013;368:709-18

9 Rivaroxaban MAGELLAN Randomized double-blind trial, 8101 hospitalized patients with acute medical illness Placebo SC x 10 d + Rivaroxaban 10 mg od x 35 d vs. Enoxaparin 40 mg od x 10 d + Placebo PO x 35 d (±4 days for all treatments) Results: Efficacy: asymptomatic proximal or symptomatic VTE up to day 10 and 35 Major + clinically relevant nonmajor bleeding Cohen et al. N Engl J Med 2013;368:513-23

10 Rivaroxaban Safety outcome: Major + clinically relevant nonmajor bleeding In acutely ill medical patients, rivaroxaban was noninferior to enoxaparin for standard-duration thromboprophylaxis. Extended-duration rivaroxaban reduced the risk of VTE. Rivaroxaban was associated with an increased risk of bleeding Cohen et al. N Engl J Med 2013;368:513-23

11 Apixaban AMPLIFY Randomized double-blind trial, 5395 patients with acute VTE Apixaban 10 mg bid x 7 d then 5 mg bid x 6 mo vs. Enoxaparin + warfarin A fixed-dose regimen of apixaban alone was noninferior to conventional therapy for the treatment of acute VTE and was associated with significantly less bleeding Agnelli et al. N Engl J Med 2013;369:

12 Apixaban AMPLIFY-EXT (ASH 2012) Randomized double-blind trial, 2486 patients who completed 6-12 months anticoagulation for VTE with clinical equipoise regarding ongoing/d/c AC Apixaban 2.5 and 5 mg bid vs. Placebo x 12 months Extended anticoagulation with apixaban at either a treatment dose (5 mg) or prophylactic dose (2.5 mg) reduced the risk of recurrent venous thrombombolism without increasing the rate of major bleeding Agnelli et al. N Engl J Med 2013;369:

13 Edoxaban Hokusai-VTE Randomized double-blind non-inferiority trial, 8240 patients with acute VTE Edoxaban 60 mg od vs. warfarin (INR 2-3) x 3-12 months Edoxaban 30 mg od if CrCl ml/min or weight <60 kg All received enoxaparin or UFH x 5 days preceding treatment Edoxaban administered once daily after initial treatment with heparin was noninferior to high-quality standard therapy and caused significantly less bleeding in a broad spectrum of patients with VTE, including those with severe PE Buller et al. N Engl J Med 2013;369:

14 Edoxaban ENGAGE AF-TIMI 48 Randomized double-blind double-dummy trial comparing 2 doses of edoxaban vs. warfarin in 21,105 patients with mod-high risk AF (CHADS 2 2) Edoxaban 30 mg or 60 mg od vs. warfarin (INR 2-3) Edoxaban dose halved if CrCl ml/min or weight <60 kg Both once-daily regimens of edoxaban were noninferior to warfarin with respect to the prevention of stroke or systemic embolism and were associated with significantly lower rates of bleeding and death from cardiovascular causes Giugliano et al. N Engl J Med. Published online Nov 19, 2013

15 Health Canada approved indications No new Health Canada approved indications in 2013: DVT prevention in total hip or total knee surgery Dabigatran (Pradaxa ) and Rivaroxaban (Xarelto ) 2008 Apixaban (Eliquis ) March 2012 Prevention of stroke/systemic embolism in patients with atrial fibrillation Dabigatran (Pradaxa ) November 2010 Rivaroxaban (Xarelto ) January 2012 Apixaban (Eliquis ) December 2012 DVT treatment (without symptomatic PE) Rivaroxaban (Xarelto ) February 2012

16 Key News Out of ASH: NOACs and cancer Current recommended treatment of VTE in cancer patients is LMWH NOACs are increasingly used for VTE treatment Great interest in whether NOACs can be used in cancer patients Cancer patients have generally been excluded from trials evaluating NOACs; no specific trials addressing this question

17 Key News Out of ASH: NOACs and cancer Edoxaban for long-term treatment of venous thromboembolism in cancer patients (Raskob et al.) Oral Session 332 (Antithrombotic therapy), Monday December 9, 2013, 7:00 AM Influence of active cancer on the efficacy and safety of dabigatran versus warfarin for the treatment of acute venous thromboembolism: A pooled analysis from RE- Cover and RE-Cover II (Schulman et al.) Oral Session 332 (Antithrombotic therapy: Basic Research and Cancer Trials), Monday December 9, 2013, 5:45 PM

18 Edoxaban for long-term treatment of venous thromboembolism in cancer patients (Hokusai-VTE) Raskob GE et al. Antithrombotic Therapy: Clinical Trials (Oral) Monday December 9, 2013 Randomized, double-blind, non-inferiority trial Edoxaban 60 (30) mg od vs. warfarin (heparin preceding) N=8,292 patients with acute symptomatic proximal DVT and/ or PE Excluded patients with active cancer in whom long-term LMWH was anticipated, but patients with history of cancer or active cancer and LMWH was not planned (availability, MD judgment or patient preference) were included N=771 (9.3%) cancer patients (208 active; 563 history) Median duration of treatment (E vs. W): 267 vs. 266 days

19 Edoxaban for long-term treatment of venous thromboembolism in cancer patients (Hokusai-VTE) Raskob GE et al. Antithrombotic Therapy: Clinical Trials (Oral) Monday December 9, 2013 Patients with active cancer Edoxaban Warfarin Hazard Ratio (95% CI) Recurrent VTE 4/109 (3.7%) 7/99 (7.1%) 0.55 ( ) Clinically relevant bleeding (major + non-major) All cancer patients 20/109 (18.3%); 5 major 25/99 (25.3%); 3 major 0.72 ( ) Recurrent VTE 14/378 (3.7%) 28/393 (7.1%) 0.53 ( ) Clinically relevant bleeding (major + non-major) Patients without cancer 47 (12.4%); 10 major 74 (18.8%); 13 major 0.64 ( ) Recurrent VTE 103/3658 (2.8%) 99/3629 (2.7%) 1.03 ( , p=0.004 for non-inferiority) Clinically relevant bleeding (major + non-major) 280/3658 (7.7%); 39 major 330/3629 (9.1%); 48 major 0.83 ( , p=0.022)

20 Edoxaban for long-term treatment of venous thromboembolism in cancer patients (Hokusai-VTE) Raskob GE et al. Antithrombotic Therapy: Clinical Trials (Oral) Monday December 9, 2013 Edoxaban is as effective, and possibly more effective, than warfarin in cancer patients with VTE. In such patients, bleeding is appreciable during anticoagulant therapy, and may potentially be reduced by edoxaban therapy. Additional studies of edoxaban for initial and long-term therapy of VTE in cancer patients are indicated, with LMWH as the comparitor, and including lower doses of edoxaban to determine if bleeding can be further reduced without loss of efficacy

21 Influence of active cancer on the efficacy and safety of dabigatran versus warfarin for the treatment of acute venous thromboembolism: A pooled analysis from RE-Cover and RE-Cover II Schulman S et al. Antithrombotic Therapy: Basic Research & Cancer Trials (Oral) Monday December 9, 2013 Dabigatran 150 mg bid was non-inferior to warfarin (INR 2-3) in patients with acute VTE with regards to recurrent VTE and major bleeding Prespecified subgroup analysis in patients with/without active cancer Active cancer: Diagnosis or treatment of cancer within 5 years before enrolment or recurrent or metastatic cancer Recurrent VTE or VTE related death (D vs. W) 68/2553 (2.7%) vs. 62/2554 (2/4%); HR 1.09 (0.77, 1.54) Cancer associated with increased likelihood of VTE or VTErelated death Major bleeding less frequent with D vs. W

22 Influence of active cancer on the efficacy and safety of dabigatran versus warfarin for the treatment of acute venous thromboembolism: A pooled analysis from RE-Cover and RE-Cover II Schulman S et al. Antithrombotic Therapy: Basic Research & Cancer Trials (Oral) Monday December 9, 2013 There was a significantly higher frequency of recurrent VTE or VTE-related mortality among patients who had cancer, but the efficacy of dabigatran vs. warfarin was similar irrespective of cancer status. The incidence of bleeding events was similar or numerically lower with dabigatran than with warfarin across cancer subgroups

23 Key News Out of ASH: Refining the diagnosis of PE Age-adjusted D-dimer cut-off levels to rule out pulmonary embolism: A prospective outcome study (Righini M et al.) Late-breaking abstracts LBA-4, Tuesday December 10, 2013, 7:30 9:00 AM

24 Age-adjusted D-dimer cut-off levels to rule out pulmonary embolism: A prospective outcome study Righini et al. Late-breaking abstracts LBA-4, Tuesday December 10, 2013 Negative D-dimer and low pre-test probability (using prediction rules) can rule out diagnosis of PE without need for imaging tests ~1/3 outpatients fall into this category D-dimer levels increase with age Age-adjusted D-dimer cut-off value = patient s age x 10 in patients aged >50 years, in ug/l Multicentre prospective management outcome study Patients presenting to ER with suspected PE assessed using clinical PTP, D-dimer and CTPA Patients with D-dimer between usual threshold of 500 ug/l and their age-adjusted cut-off no CTPA, no treatment and followed x 3 months

25 Age-adjusted D-dimer cut-off levels to rule out pulmonary embolism: A prospective outcome study Righini et al. Late-breaking abstracts LBA-4, Tuesday December 10, 2013 N=3377 patients, mean age 62 years, 57% female Proportion of confirmed PE 18% Non-high clinical probability N=2927 D-dimer <500 ug/l N=832 (28.4%) D-dimer 500-AACT N=345 (11.8%) Received AC for another indication N=18 Patients followed N=327 Death N=7 Underwent VTE testing N=7 Failure rate 1/327 (0.3%, %) Negative testing N=6 Positive testing N=1

26 Age-adjusted D-dimer cut-off levels to rule out pulmonary embolism: A prospective outcome study Righini et al. Late-breaking abstracts LBA-4, Tuesday December 10, pts >75 years 697 (88.3%) had non-high clinical probability Proportion of patients with negative D-dimer using age-adjusted cutoff : 211/697 (30.3%); none had VTE in follow-up D-dimer <500 ug/l N=50 (7.2%) Non-high clinical probability N=697 D-dimer 500-AACT N=161 (23.1%) Age-adjusted D-dimer cut-off can be used in clinical practice in the ER in patients with suspected PE Combined with clinical PTP, it increases the number of patients in whom PE can be excluded without imaging, particularly among elderly patients D-dimer > 500 ug/l but under age-adjusted cut-off safely excludes diagnosis of PE with 3 month VTE risk similar to patients with D- dimer <500 ug/l or after negative pulmonary angiography

27 Canadian Perspective There are an increasing number of anticoagulant options for prophylaxis post joint replacement, stroke prevention in atrial fibrillation and for treatment of VTE in Canada Selection of optimal NOAC Managing NOAC bleeding complications NOACs may be used for extended duration of anticoagulation and offer decreased recurrence with low bleeding rates Use of NOACs in cancer patients looks promising Diagnosis of PE in ER may be more efficient and reduce exposure to imaging tests

28 Thank you! Enjoy New Orleans and ASH 2013