scholarly journals Comparative Effectiveness and Safety of Extended Anticoagulant Therapy Among Medicare Beneficiaries with Venous Thromboembolism

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 178-178
Author(s):  
Haesuk Park ◽  
Hye-Rim Kang ◽  
Pei-Lin Huang ◽  
Wei-Hsuan Lo-Ciganic ◽  
Eric A Dietrich ◽  
...  

Abstract Introduction: Approximately 30% of patients with venous thromboembolism (VTE) experience a recurrence within 10 years of the initial event with their recurrence risk peaking during the first 6-12 months. Two large randomized clinical trials AMPLIFY-EXT and PADIS-PE reported that extended treatment with apixaban and warfarin beyond 6 months of initial treatment reduced recurrent VTE without increasing the rate of major bleeding compared to placebo, respectively. Little is known about real-world effectiveness and safety of extended oral anticoagulation beyond 6 months of initial treatment for Medicare beneficiaries with VTE, despite the fact that VTE disproportionately affects the elderly. We assessed the effectiveness and safety of extended use of apixaban and warfarin beyond 6 months of initial treatment for prevention of recurrent VTE and adverse major bleeding events among Medicare beneficiaries with newly diagnosed VTE. Methods: A retrospective cohort study using 2014-2018 Medicare data (5% samples in 2014-2016 and 15% samples of Medicare beneficiaries in 2017-2018) was conducted for patients aged ≥18 years with a diagnosis of deep vein thrombosis or pulmonary embolism ascertained from inpatient claims. Patients were included if they initiated anticoagulants within 30 days of their first VTE diagnosis, completed 6 months of therapy defined as ≥83% proportion days covered with oral anticoagulants during the initial 6-month period, and received extended treatment with either apixaban or warfarin or no extended therapy. We compared the risks of recurrent VTE and major bleeding between apixaban, warfarin, and no treatment groups. To adjust for differences in baseline characteristics and clinical factors (e.g., HAS-BLED score, active cancer, and provoked VTE) between groups, we used the stabilized inverse probability treatment weighting (IPTW) method. Follow-up continued until the occurrence of the first event, switch to the comparator, disenrollment, death, or end of the study period. Multivariable Cox proportional hazards modeling with IPTW was used to obtain adjusted hazard ratios (aHR) and 95% confidence intervals (95%CI). Results: The study cohort (mean age=74 ±12 years, 40% male, 76% White) consisted of 2,315 users of extended apixaban treatment (83% with 5 mg twice a day and 17% with 2.5 mg twice a day; mean duration=6.2 months), 2,757 users of extended warfarin treatment (mean duration=8.2 months), and 2,328 patients with no extended treatment following completion of an initial 6 months of anticoagulant treatment. The incidence rates of recurrent VTE were 0.42, 1.73, and 1.72 per 100 person-years, and those of major bleeding were 2.28, 3.62, and 1.43 per 100 person-years in the apixaban, warfarin, and no treatment groups, respectively (Table 1). Compared to no extended treatment, the use of apixaban was associated with an 80% decreased risk of recurrent VTE (aHR=0.19, 95%CI=0.06-0.55) without increasing the risk of major bleeding (aHR=1.19, 95%CI=0.65-2.19); the use of warfarin did not lower the risk of recurrent VTE (aHR=0.75, 95%CI=0.42-1.37) but increased the risk of major bleeding (aHR=1.92, 95%CI=1.13-3.25). Compared to the use of warfarin, the use of apixaban was associated with a decreased risk of recurrent VTE (aHR=0.26, 95% CI=0.09-0.76) and no difference in major bleeding risk (aHR=0.61, 95%CI=0.36-1.06). These findings remained consistent in subgroup (e.g., patients with provoked vs. unprovoked VTE, patients with active cancer vs. those without, and patients with chronic kidney diseases vs. those without) and sensitivity analyses (e.g., ≥92% proportion days covered with oral anticoagulants during the initial 6-month period). Conclusions: Compared to no extended therapy, extended anticoagulation with apixaban was associated with a reduced risk of recurrent VTE without increasing the risk of major bleeding, whereas warfarin did not lower risk of recurrent VTE but increased the risk of major bleeding among Medicare beneficiaries with VTE. In the head-to-head comparison, the use of apixaban was more effective than warfarin in preventing recurrent VTE, without increasing the risk of major bleeding events. Our findings suggest that apixaban is an effective and safer option for extended treatment of VTE when compared to warfarin or no treatment among Medicare beneficiaries with VTE. Figure 1 Figure 1. Disclosures Park: BMS/Pfizer Alliance American Thrombosis Investigator Initiated Research Program: Research Funding. Kang: BMS/Pfizer Alliance American Thrombosis InvestigatorInitiated Research Program: Research Funding. Huang: BMS/Pfizer Alliance American Thrombosis Investigator Initiated Research Program: Research Funding. Lo-Ciganic: MERCK: Research Funding; BMS/Pfizer Alliance American Thrombosis Investigator Initiated Research Program: Research Funding. Dietrich: BMS/Pfizer Alliance American Thrombosis Investigator Initiated Research Program: Research Funding. Murphy: North American Thrombosis Foundation: Honoraria. DeRemer: BMS/Pfizer Alliance American Thrombosis Investigator Initiated Research Program: Research Funding; Portola Pharmaceuticals: Current equity holder in publicly-traded company; BMS advisory board attendee: Honoraria.

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 4059-4059
Author(s):  
Hye-Rim Kang ◽  
Bobby L Jones ◽  
Wei-Hsuan Lo-Ciganic ◽  
Christina E DeRemer ◽  
Eric A Dietrich ◽  
...  

Abstract Introduction: The optimal duration of extended oral anticoagulant treatment for patients with venous thromboembolism (VTE) beyond the initial 3 to 6 months of the treatment remains undetermined. Group-based trajectory modeling (GBTM) is a data-driven method that can categorize patients with similar longitudinal adherence patterns over time into distinct subgroups. This study identified distinct patient subgroups with similar adherence trajectories of extended treatment of direct-acting oral anticoagulants (DOACs), and then examined the association between adherence trajectories and the risk of recurrent VTE and major bleeding among patients with VTE. Methods: We identified patients ≥18 years with a diagnosis of deep vein thrombosis (DVT) or pulmonary embolism (PE) from inpatient claims using 2013-2019 Truven Commercial and Medicare Supplemental database. Patients were included if they initiated anticoagulants within 30 days of their first VTE diagnosis, completed 6 months of therapy-defined as ≥83% proportion days covered (PDC) with oral anticoagulants during the initial 6-month treatment period, and had extended treatment with any DOACs or no extended therapy. Based on the monthly PDC as the DOAC adherence measure, we used GBTM to identify DOAC adherence trajectories during 6 months of the extended treatment. The final trajectory model was chosen by assessing the Bayesian information criteria, Nagin's criteria, and having at least 10% of patients in each trajectory group for improving clinical utility. We compared recurrent VTE and major bleeding among adherence trajectory subgroups. Patients were followed up from the initiation of the extended treatment until the occurrence of the study outcomes, discontinuation of DOACs, switching to warfarin, end of study period, or end of enrollment, whichever occurred first. Cox proportional hazard modeling with inverse probability treatment weighting (IPTW) was used to obtain hazard ratios (HR) and 95% confidence intervals (95% CI). Results: The study cohort (mean age=58.7 years and 51.1% males) consisted of 10,960 patients with extended treatment of DOACs (4,294 apixaban, 6,409 rivaroxaban, 238 dabigatran, and 19 edoxaban users) with a mean treatment duration of 7.7 months and 5,133 patients with no extended treatment following completion of an initial 6 months of anticoagulant treatment. The final GBTM models identified four distinct adherence trajectories for extended therapy including (1) patients with consistent adherence (group 1, 40.7%), (2) patients with gradually declining adherence (group 2, 14.3%), (3) patients with rapidly declining adherence (group 3, 13.1%), and (4) patients with no extended treatment (reference group, 31.9%) (Figure 1). The incidence rates of recurrent VTE were 18.6, 46.9, 84.1, and 160.7 per 10,000 person-years, and those of major bleeding were 61.0, 125.1, 168.3, and 48.7 per 10,000 person-years in group 1, group 2, group 3, and the reference group, respectively. After IPTW, demographics and clinical characteristics (e.g., HAS-BLED bleeding risk score, provoked VTE) were comparable across the four trajectory groups with <0.1 of the standardized mean difference for each pairwise comparison. Compared to the reference group, group 1 (HR=0.09, 95% CI=0.05-0.17) and group 2 (HR=0.16, 95% CI=0.04-0.58) had decreased risk of recurrent VTE without increasing risk of major bleeding (HR=1.26, 95% CI=0.76-2.10 in group 1, HR=2.28, 95% CI=0.96-5.36 in group 2). There was no difference in the risk of recurrent VTE (HR=0.32, 95% CI=0.09-1.16) in group 3 but they had an increased risk of major bleeding (HR=2.69, 95% CI=1.00-7.23). The findings were consistent across different types of DOACs, suggesting a class effect of DOACs as extended therapy. Conclusions: We identified 4 distinct trajectories of DOAC adherence during the 6 months of extended therapy among patients who completed 6 months of initial treatment. Compared to no extended treatment, persistent use of DOACs during extended treatment was associated with a lower risk of recurrent VTE without increasing major bleeding risk, whereas a rapid decline in adherence was associated with an increased risk of major bleeding with no difference in the risk of recurrence. Our findings provide evidence on the benefits of continuing and being adherent to extended anticoagulant treatment in patients with VTE without increasing the risk of major bleeding. Figure 1 Figure 1. Disclosures Kang: BMS/Pfizer Alliance American Thrombosis Investigator Initiated Research Program: Research Funding. Jones: BMS/Pfizer Alliance American Thrombosis Investigator Initiated Research Program: Research Funding. Lo-Ciganic: BMS/Pfizer Alliance American Thrombosis Investigator Initiated Research Program: Research Funding; MERCK: Research Funding. DeRemer: BMS advisory board attendee: Honoraria; Portola Pharmaceuticals: Current equity holder in publicly-traded company; BMS/Pfizer Alliance American Thrombosis Investigator Initiated Research Program: Research Funding. Dietrich: BMS/Pfizer Alliance American Thrombosis Investigator Initiated Research Program: Research Funding. Huang: BMS/Pfizer Alliance American Thrombosis Investigator Initiated Research Program: Research Funding. Murphy: North American Thrombosis Foundation: Honoraria. Park: BMS/Pfizer Alliance American Thrombosis Investigator Initiated Research Program: Research Funding.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1104-1104 ◽  
Author(s):  
Scott T Tagawa ◽  
Ilene c Weitz ◽  
Casey L. O'Connell ◽  
Leanne Rochanda ◽  
Mckenna Archer ◽  
...  

Abstract Abstract 1104 Background: Venous thromboembolism (VTE) is a major complication in cancer patients. The traditional treatment algorithm for VTE of UF or LMW heparin followed warfarin is associated with a higher risk of recurrent VTE and bleeding in cancer patients. A recent randomized trial has demonstrated that initial treatment and secondary prophylaxis with LMWH is associated with a lower VTE recurrence when compared to secondary prophylaxis with warfarin. We initiated a single arm Phase 2 IRB approved study to evaluate the efficacy and safety of once daily tinzaparin for the initial treatment and extended prophylaxis (6 months) of VTE in cancer patients. Included in this study was a prospective analysis of plasma biomarkers to assess whether any biomarkers could predict treatment failure or be predictive of patient survival. Methods: Patients (pts)with objectively confirmed symptomatic deep vein thrombosis (DVT), pulmonary embolism (PE) or unexpected PE detected on staging CT scans by the criteria of OConnell et al. (JCO 24:4928, 2006) were eligible for this study, if they had an ECOG score <2 and an estimated 6 month survival. After informed consent, treatment was initiated with tinzaparin 175 U/Kg for 6 months. Planned enrollment was 100 pts. Pts who completed the 6 month study could continue on treatment for an additional 6 months if clinically appropriate. All pts who received at least one injection of tinzaparin were evaluable for efficacy and safety. Study endpoints were objectively confirmed DVT, PE or major bleeding events. Serial blood samples were obtained prior to treatment, at 1 wk, 1 month, 3 months and 6 months. Biomarkers to be studied included D-dimer (D-D), Thrombin-antithrombin complex (TAT), interleukin 6 and 8 (Il-6, Il-8) and plasma tissue factor. Only pts in whom the pretreatment, I week and 1 month blood samples were collected were included in the biomarker analysis. Results: At time of this submission 91 pts were treated on study. Of 91 pts enrolled 39 (42.9%) have completed the 6 months and 5 (5.5%) remain on active treatment. Eight (8.8%) pts withdrew from study for hospice care and one pt was withdrawn due to poor compliance. Forty-two (46%) pts died before 6 months. Ten (11%) pts continued on treatment after 6 months and one pt transitioned to warfarin treatment. Treatment endpoints included 8 (8.8%) pts with recurrent VTE (5 DVT, 3 PE); 2 occurred within the first 4 wks on treatment and the 6 events before month 3. No recurrent VTE occurred after 12wks. Three pts (3%) had major bleeding events. There were no fatal thrombotic or bleeding events. All deaths were considered due to progressive cancer, although the possible fatal VTE in pts who died at home or in hospice could not be excluded. There were 76 (83.5%) pts were evaluable for the biomarker study. Biomarker data failed to show a correlation between the level of D-D, TAT or Il-6 and patient survival from the time of their thrombotic event. However, in pts who developed recurrent VTE after 1 month, the D-D level at month 1 was higher than the pretreatment in 4/6 (66.7%) patients compared to 8/70 (11.4%) pts with no recurrence in whom month 1 samples were obtained. Conclusion: In this prospective study of tinzaparin for initial treatment and secondary prophylaxis of cancer-associated VTE, treatment appeared both safe and efficacious. Our recurrent VTE event rate of 8.8% compares favorably with the 8% recurrent VTE reported in the pts treated with dalteparin. The 3% of patients who had major bleeding events also compares favorably with the CLOT trial. Survival was difficult to predict at the time of enrollment since 46% failed to survive the 6 months. Biomarker data failed to predict survival, but patients who recurred after the first month were more likely to have month 1 D-D levels greater than pretreatment. The reason for the failure of tinzaparin treatment to effectively suppress thrombin generation in these patients remains unexplained. Disclosures: Tagawa: Leo Pharmaceutical: Research Funding; Celgene: Research Funding. Liebman:Leo Pharmaceutical: Research Funding; Celgene: Research Funding.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 423-423 ◽  
Author(s):  
Margarita Kushnir ◽  
Yun Choi ◽  
Ruth Eisenberg ◽  
Devika Rao ◽  
Seda Tolu ◽  
...  

Abstract Background: Studies of acute venous thromboembolism (VTE) and non-valvular atrial fibrillation (AF) have shown comparable therapeutic efficacy and similar or lower bleeding risk for direct oral anticoagulants (DOACs) compared to warfarin. Because the representation of morbidly obese patients (BMI ≥40 kg/m2) in pivotal clinical trials has been minimal, efficacy and safety of DOACs in this population are unclear. Our goal was to investigate whether direct oral factor Xa inhibitors, apixaban and rivaroxaban, are as effective and safe as warfarin in morbidly obese (BMI ≥40) patients. Methods: Using our institutional database, we identified all adult patients at Montefiore Medical Center with BMI ≥40 who were started on anticoagulation with apixaban, rivaroxaban or warfarin, for either AF or VTE, between March 1, 2013 and March 1, 2017. We reviewed charts to obtain detailed information on patient demographics and to document clinical outcomes of recurrent VTE, ischemic stroke (CVA) and bleeding from the first prescription date to the earliest of a thrombotic event, discontinuation of medication, death, or June 30, 2017. VTE and CVA episodes were confirmed by imaging (compression sonography, CT scans, ventilation/perfusion scans, MRIs). Bleeding events were classified according to criteria from the Control of Anticoagulation Subcommittee of the International Society on Thrombosis and Haemostasis. Analyses were stratified by anticoagulation indication. Chi-squared tests or Fisher's exact tests were used to assess statistical significance of the differences in VTE, CVA and bleeding rates between anticoagulant cohorts. Differences in times from first prescription date to VTE, CVA and bleeding were analyzed with Kaplan-Meier curves, Log-rank tests, and Cox proportional hazards models. Data were adjusted for age, CHA2DS2-VASc, and Charlson scores. Subgroup analyses were performed for patients with BMI ≥50 kg/m2. Results: Data on 795 patients were collected. In 366 patients with a history of VTE, the rates of recurrent VTE were low and comparable among the apixaban, rivaroxaban and warfarin cohorts [1/47 (2.1%), 3/152 (2%), and 2/167 (1.2%), respectively, p=0.74]. In the subgroup of individuals with BMI ≥50 kg/m2 (n=92), none of the 40 DOAC patients had recurrent VTE. The rates of clinically relevant bleeding, including major bleeding, among VTE patients, were comparable between the three cohorts. Among the 429 patients with AF, stroke rates were also low and similar among anticoagulant cohorts [1/103 (1%) for apixaban, 4/174 (2.3%) for rivaroxaban, and 2/152 (1.3%) for warfarin, p=0.71]. CVAs were similarly rare in patients with BMI ≥50 (1/19 patients on apixaban, 0/37 on rivaroxaban and 1/44 patients on warfarin). In the AF sample, there was no statistically significant difference in the rate of bleeding, including major bleeding, among the 3 cohorts. In an analysis with combined DOAC cohort (apixaban + rivaroxaban vs. warfarin), the recurrent VTE and stroke rates were still low and comparable. There were more major bleeding events in AF patients on warfarin than the combined DOAC cohort (7.9% vs. 2.9%, p=0.02), a finding that became non-significant when adjusted for age, CHA2DS2-VASc, and Charlson scores (p=0.06). The rates of bleeding, including major bleeding, were comparable among the three anticoagulants in both VTE and AF patients with BMI ≥50. Conclusions: Our study is the largest study examining morbidly obese patients on DOACS and provides further evidence of comparable efficacy and safety of the direct oral anti-Xa inhibitors, compared to warfarin, in morbidly obese patients with AF and VTE. Disclosures Kushnir: Janssen: Research Funding. Billett:Bayer: Consultancy; Janssen: Research Funding.


Blood ◽  
2017 ◽  
Vol 130 (Suppl_1) ◽  
pp. LBA-6-LBA-6
Author(s):  
Gary E. Raskob ◽  
Nick Van Es ◽  
Peter Verhamme ◽  
Marc Carrier ◽  
Marcello Di Nisio ◽  
...  

Abstract On behalf of the Hokusai VTE Cancer Investigators The treatment of cancer-associated venous thromboembolism (VTE) is challenging because these patients are at increased risk of both recurrent VTE and major bleeding. Low-molecular-weight heparin (LMWH) treatment is standard care for these patients, but requires daily subcutaneous injections. Guidelines recommend LMWH treatment for 6 months, but the risk-benefit beyond this time is uncertain. Direct oral anticoagulants are used for the treatment of VTE in patients without cancer, but their role in patients with cancer- associated VTE is uncertain. In this randomized, open-label non-inferiority trial, cancer patients with acute symptomatic or incidental VTE were assigned to receive LMWH for a minimum of 5 days followed by the oral factor Xa inhibitor edoxaban at a dose of 60 mg once daily (or 30 mg once daily in patients with a creatinine clearance of 30 to 50 ml per minute or a body weight below 60 kg), or subcutaneous dalteparin 200 units per kg once daily for one month followed by 150 units per kg thereafter. Patients received these regimens for up to 12 months. The primary outcome was the composite of the first recurrent VTE or major bleeding event during follow-up for 12 months. Secondary outcomes included recurrent VTE and major bleeding analyzed separately, and survival free of recurrent VTE or major bleeding. The study hypothesis was that edoxaban would be noninferior to dalteparin for the primary outcome with an upper 95% confidence interval [CI] for the hazard ratio below 1.5, and a two-sided alpha of 0.05. All outcomes were independently adjudicated by a committee without knowledge of treatment allocation. This committee also assessed the clinical severity of major bleeding events using categorical criteria defined a priori (categories 1 to 4). From July 2015 through December 2016 a total of 1050 patients were enrolled at 114 centers in 13 countries; 525 were randomized to edoxaban and 525 to dalteparin. At entry, pulmonary embolism with or without deep-vein thrombosis was present in 657 patients (63%) while the remainder had isolated deep-vein thrombosis. Of the 1050 patents, 706 (67%) had symptomatic VTE and the rest were incidental. Active cancer at entry was present in 97% of the patients and 53% had metastatic disease. 1046 patients were included in the modified-intention-to-treat analysis. The primary outcome occurred in 67 of 522 patients (12.8%) in the edoxaban group compared with 71 of 524 patients (13.5%) in the dalteparin group (hazard ratio with edoxaban, 0.97; 95% CI, 0.70 to 1.36; P = 0.0056 for noninferiority) for a risk difference (edoxaban minus dalteparin) of - 0.7% (95% CI, - 4.8 to 3.4). The difference in risk for recurrent VTE was -3.8 % (95% CI, -7.1 to -0.4), whereas the corresponding difference in risk for major bleeding was 3.1% (95% CI, 0.5 to 5.7). The frequencies of severe major bleeding events (categories 3 and 4) were similar during treatment with edoxaban or dalteparin (12 patients in each group respectively). Survival at 12 months free of recurrent VTE and major bleeding in the edoxaban and dalteparin groups was similar (55.0% and 56.5% respectively). Oral edoxaban for up to 12 months is noninferior to subcutaneous dalteparin for the treatment of cancer-associated VTE. Disclosures Raskob: BMS: Consultancy, Honoraria; Eli Lilly: Consultancy; Janssen: Consultancy; Johnson and Johnson: Consultancy; Pfizer: Consultancy, Honoraria; Portola: Consultancy; Boehringer-Ingelheim: Consultancy; Medscape: Honoraria; Bayer Healthcare: Consultancy; Daiichi Sankyo: Consultancy, Honoraria. Van Es:Daiichi Sankyo: Honoraria; Pfizer: Honoraria. Verhamme:Daiichi Sankyo: Consultancy, Honoraria, Research Funding; Bayer Healthcare: Consultancy, Honoraria, Research Funding; BMS: Consultancy, Honoraria; Boehringer Ingelheim: Consultancy, Research Funding; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Portola: Consultancy; Medscape: Honoraria; Leo: Honoraria, Research Funding; Sanofi Aventis: Research Funding; Medtronic: Honoraria, Membership on an entity's Board of Directors or advisory committees. Carrier:Daiichi Sankyo: Consultancy, Honoraria; BMS: Consultancy, Research Funding; Leo: Consultancy, Research Funding; Pfizer: Consultancy, Honoraria. Di Nisio:Daiichi: Consultancy, Honoraria. Garcia:Daiichi Sankyo: Honoraria, Research Funding; BMS: Consultancy; Boehringer Ingelheim: Consultancy; Janssen: Consultancy, Research Funding; Pfizer: Consultancy, Honoraria; Medscape: Honoraria; Incyte: Consultancy, Honoraria, Research Funding. Grosso:Daiichi Sankyo: Employment. Kakkar:Daiichi Sankyo: Consultancy, Honoraria; Bayer Healthcare: Consultancy, Research Funding; Boehringer Ingelheim: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Sanofi SA: Consultancy, Honoraria; Verseon: Consultancy, Honoraria. Kovacs:Daiichi Sankyo: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; Bayer: Honoraria; Bristol Myers Squibb: Research Funding. Mercuri:Daiichi Sankyo: Employment, Patents & Royalties: pending properties of edoxaban . Meyer:BMS Pfizer: Research Funding; Leo: Other: travel support; Stago: Other: travel support. Segers:Ionis: Research Funding; Daiichi Sankyo: Research Funding; Janssen: Research Funding. Shi:Daiichi Sankyo: Employment. Wang:Daiichi Sankyo: Honoraria. Yeo:Daiichi Sankyo: Honoraria, Research Funding; Bayer Healthcare: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Boehringer Ingelheim: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Leo: Consultancy, Honoraria. Zhang:Daiichi Sankyo: Employment. Zwicker:Daiichi Sankyo: Honoraria; Quercegen Pharma: Research Funding; Parexel: Consultancy. Weitz:Daiichi-Sankyo: Consultancy, Honoraria; Ionis Pharmaceuticals: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Novartis Pharmaceuticals: Consultancy, Honoraria; Merck & Co., Inc.: Consultancy, Honoraria; Pfizer, Inc.: Consultancy, Honoraria; Portola Pharmaceuticals: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria; Medscape: Consultancy, Honoraria; Boehringer Ingelheim: Consultancy; Bayer HealthCare Pharmaceuticals: Consultancy, Honoraria. Büller:Daiichi Sankyo: Consultancy, Honoraria; Bayer: Consultancy, Honoraria; BMS: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Boehringer Ingelheim: Consultancy, Honoraria; Portola: Consultancy; Medscape: Honoraria; Eli Lilly: Consultancy; Sanofi Aventis: Consultancy; Ionis: Consultancy.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 2439-2439 ◽  
Author(s):  
Margarita Kushnir ◽  
Radhika Gali ◽  
Mariam Alexander ◽  
Henny Heisler H. Billett

Background: Over 200,000 people underwent weight loss surgery in the United States in 2017. The absorption of numerous drugs has been shown to be altered in patients after bariatric procedures, as gastrointestinal absorptive surface, food volume, and gastric pH all affect bioavailability. Dosing of warfarin, which is commonly used for the treatment of venous thromboembolism (VTE), often needs to be adjusted, based on INR, after bariatric surgery. Since direct oral anticoagulants (DOACs), which are rapidly replacing warfarin as standard anticoagulant therapy, are not monitored, there is concern regarding their efficacy and safety in patients who have had bariatric surgery, particularly rivaroxaban, which is absorbed primarily in the stomach and must be taken with food at therapeutic doses. One study found that 9 out of 9 apixaban patients (but only 2 of 7 rivaroxaban patients) had levels that fell within the expected range after bariatric surgery. Effects of bariatric surgery on DOACs may be further complicated by baseline obesity and subsequent weight loss of the patients. The goal of our current study is to determine whether DOACs are safe and effective in preventing recurrent VTE in patients who have undergone bariatric surgery. Methods: Using our institutional database, we identified all adult patients (age ≥18 years) with a history of bariatric surgery (gastric banding, sleeve gastrectomy, and Roux-en-Y gastric bypass) who were started on anticoagulation with apixaban or rivaroxaban for VTE, between July 1, 2013 and June 30, 2018. We performed retrospective chart review to obtain information on patient demographics, BMI and type of bariatric surgery. We documented clinical outcomes of recurrent VTE and bleeding from the first prescription date to the earliest of a thrombotic event, discontinuation of medication, death, or the end of study period, June 30, 2018. VTE events were confirmed by a review of imaging studies (compression ultrasonography, ventilation/perfusions scans, and CT scans). Bleeding events were included if they met criteria for clinically relevant non-major bleeding and/or major bleeding according to the Subcommittee on Control of Anticoagulation of the Scientific and Standardization Committee of the International Society on Thrombosis and Haemostasis. Safety outcomes included major bleeding (MB) and clinically relevant non-major bleeding (CRNMB). We also compared VTE recurrence and bleeding rates between the post-bariatric surgery patients and patients with BMI >40 from our prior study. Chi- squared tests were used to assess statistical significance of the differences in recurrent VTE and bleeding rates between anticoagulant cohorts. Results: Data on 102 patients were collected: 42 patients on apixaban and 60 patients on rivaroxaban. Our population was predominantly female (82.4%) with a mean age of 48.5 years and a median BMI of 35.7 at initiation of anticoagulation. Gastric bypass was the most common bariatric procedure (51%), followed by sleeve gastrectomy (37.3%), and gastric banding (11.8%). There were no recurrent VTE events in the apixaban cohort with a median follow-up duration of 137 days. Among patients on rivaroxaban, with a median follow-up of 232 days, there was one recurrent VTE (1.7%) in a patient with a BMI of 54 at the time of event. When we compared VTE recurrence rates of our combined DOAC cohort (apixaban + rivaroxaban) between our general morbidly obese population, from a prior study at our institution, and post-bariatric surgery patients, there was no statistically significant difference (2.0% vs. 1.0%, respectively, p=0.5). In bariatric surgery patients, one CRNMB event was recorded in apixaban group (2.4%) while 4 major bleeding events occurred on rivaroxaban (6.7%), p=0.3. There was no significant difference in the rate of composite MB and CRNMB between the general obesity and bariatric surgery patients (8.0% vs. 4.9%, respectively, p=0.3). Conclusions: In a review of post-bariatric surgery patients on anticoagulation for VTE, we found low rates of recurrent VTE for patients on DOACs. Although we had a relatively small sample size, the incidence of VTE recurrence was not higher in this cohort than was found in our previously published study of general obesity population. Prospective studies are needed to further investigate the efficacy and safety of direct oral anticoagulants in patients after bariatric surgery. Table. Disclosures Kushnir: Janssen Pharmaceuticals: Research Funding. Billett:Janssen: Research Funding.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 2528-2528 ◽  
Author(s):  
Alym Abdulla ◽  
Wendy Davis ◽  
Namali Ratnaweera ◽  
Brooke Scott ◽  
Agnes Yuet Ying Lee

Abstract Background Venous thromboembolism (VTE) is a major cause of morbidity and mortality in patients with cancer. Despite therapeutic anticoagulation, the risks of recurrent VTE and major bleeding are approximately 10% and 5%, respectively, during the first 6 months of treatment. Overall mortality ranges from 25% to 40%, depending on the study population. Knowing the case fatality rates of these outcomes is also important for weighing the relative risks and benefits of anticoagulation in patients with cancer-associated VTE but these rates have not been reported previously. Objective To determine the incidence of recurrent VTE and major bleeding events and to calculate the case fatality rates of these outcomes in patients undergoing anticoagulation for cancer-associated VTE. Methods An electronic search of MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials from January 1980 to May 2018 was performed. English language publications (observational studies and randomized controlled trials [RCTs]) that reported on patients with active cancer and VTE who received anticoagulation with low molecular weight heparin (LMWH), vitamin K antagonist (VKA), or a direct oral anticoagulant (DOAC) for at least 3 months were retrieved for review. In addition, a hand search of references of review articles was done to complement the electronic literature search. Studies that provided information on recurrent VTE, major bleeding events, mortality, and causes of death were included in analyses. Retrospective studies and prospective cohorts with fewer than 50 patients were excluded. Two reviewers independently screened for study eligibility and extracted data onto standardized forms. Study outcomes were recurrent VTE, major bleeding and death. Pooled proportions with 95% confidence intervals (CI) were calculated according to anticoagulant treatment and study design. Results The search identified 7327 studies of which 29 studies (15 prospective cohort studies and 14 randomized controlled trials) were included. Data from 8000 cancer patients followed for a total of 4786 patient-years (range 3 to 36 months) were summarized. The rate of recurrent VTE and fatal recurrent VTE were 15.7% (95% CI, 14.4% to 17.1%) and 2.5% (95% CI, 2.0% to 3.0%) per patient-year of follow-up, respectively, with a case fatality rate of 15.8% (95% CI, 12.7% to 18.8%). A sub-analysis revealed case fatality rates for recurrent VTE to be 16.3% (95% CI, 12.2% to 20.4%) for LMWH, 20.4% (95% CI, 14.0% to 26.8%) for VKA, and 10.8% (95% CI, 3.2% to 18.3%) for DOAC therapies. The rate of major bleeding and fatal major bleeding events were 6.4% (95% CI, 5.5% to 7.3%) and 1.2% (95% CI, 0.8% to 1.6%) per patient-year of follow-up, respectively, with a case fatality rate of 12.3% (95% CI, 8.7% to 15.9%). A sub-analysis revealed case fatality rates for major bleeding events to be 14.9% (95% CI, 9.6% to 20.2%), 27.9% (95% CI, 14.5% to 41.3%), and 1.9% (95% CI, 0% to 5.5%) for LMWH, VKA, and DOAC therapies, respectively. Among RCTs, case fatality for recurrent VTE was 17.3% (95% CI, 13.5% to 21.2%) and for major bleeding was 10.8% (95% CI, 3.2% to 18.3%). Among prospective cohort studies, respective case fatality rates were 12.8% (95% CI, 8.0% to 17.5%) and 15.3% (95% CI, 8.6% to 22.0%). Studies were heterogeneous in the duration of follow up and their reporting of the causes of death and definition of fatal PE. Conclusion The incidences of recurrent VTE and major bleed events are high in patients with cancer-associated VTE on anticoagulant therapy. Case fatality from recurrent thrombosis is higher than the case fatality from major bleeding. Differences among various anticoagulants likely reflect patient selection bias and heterogeneity of studies. Disclosures Lee: BMS: Research Funding; Bayer: Consultancy, Honoraria; LEO Pharma: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Servier: Honoraria.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1234-1234
Author(s):  
Joseph R. Shaw ◽  
Tinghua Zhang ◽  
Gregoire Le Gal ◽  
James Douketis ◽  
Marc Carrier

Abstract Background: Atrial fibrillation (AF) is a common disorder that will affect up to 5.6 million patients in the U.S. by 2050. Both direct oral anticoagulants (DOACs) and vitamin K antagonists (VKAs), typically warfarin, are used for stroke prevention in AF and such patients frequently undergo invasive procedures requiring anticoagulant interruption. Temporary interruption of anticoagulants can be associated with significant morbidity and mortality in the form of thromboembolic and bleeding complications. DOACs have a short half-life and fast onset of action, thereby facilitating their perioperative management as compared to VKAs. Despite important differences in perioperative management and pharmacokinetics between DOACs and VKAs, there is a paucity of data comparing perioperative outcomes in DOAC and VKA-treated patients. Methods: We undertook a single-center, retrospective chart review that compared consecutive DOAC- or warfarin-treated patients with AF who underwent perioperative anticoagulant interruption for invasive procedures between January 2017 and March 2018. Perioperative warfarin interruption was done as per CHEST guidelines (Douketis et al. Chest 141,2 Suppl). Perioperative bridging with low-molecular-weight heparin was only used for patients with CHADS2 scores of 5-6 or in patients with stroke within the past 6 months. Perioperative interruption of DOACs was done as per Thrombosis Canada guidelines, with anticoagulation held for 3 half-lives prior to low bleeding risk procedures and 5 half-lives for high bleeding risk procedures. Primary outcomes included the 30-day post-operative thromboembolic and major bleeding rates. Secondary outcomes included the 30-day clinically relevant non-major bleeding (CRNMB) andl mortality rates. Major bleeding and CRNMB were defined according to ISTH definitions. Procedural bleeding risk was defined as per Schulman et al (Circulation 2015; 132(3)). Outcome events were independently adjudicated by two investigators. Outcomes from patients on DOACs and VKAs were compared. Demographic data was analyzed on a per-patient basis, p-values were calculated using independent T-Test, Chi-Square/Fisher's Exact Test where appropriate. Outcome data was analyzed on a per-interruption basis. P-values for unadjusted and adjusted comparisons were calculated using generalized estimating equations (GEE) to account for correlation between multiple procedures on the same patients. Results: 325 DOAC patients and 199 warfarin patients underwent 351 and 221 periprocedural interruptions, respectively. Warfarin patients had a significantly higher mean age, CHADS2 score, and proportion with renal dysfunction (Table 1). There was no statistically significant difference in 30-day post-operative rates of thromboembolism, CRNMB, and overall mortality, but warfarin patients had a significantly higher rate of major bleeding (Table 2). This latter result remained statistically significant following multivariate logistic regression correction for age, CHADS2 score and level of renal dysfunction. All bleeding events occurred post-procedure, with major bleeding events occurring from post-operative day 1 to post-operative day 25. None of the warfarin patients with major bleeding received perioperative bridging; the mean international normalized ratio (INR) at the time of major bleeding was 3.3. Most major bleeding events (7/8) in the VKA arm were surgical, with a single non-surgical major-bleed (spontaneous ICH on post-operative day 15 following urological surgery). Conclusions: The perioperative interruption of warfarin was associated with a higher 30-day rate of major bleeding as compared with DOAC interruption. Re-initiation of warfarin should be done judiciously following high bleeding risk procedures, and close INR monitoring may be warranted. Disclosures Shaw: Portola Pharmaceuticals: Research Funding. Douketis:Janssen: Consultancy; Pfizer: Other: Advisory Board; Boehringer-Ingelheim: Consultancy, Other: Advisory Board, Research Funding; Portola: Other: Advisory Board; The Medicines Company: Other: Advisory Board; Daiichi-Sankyo: Other: Advisory Board; Biotie: Other: Advisory Board; Bayer: Other: Advisory Board; Sanofi: Consultancy, Other: Advisory Board; BMS: Other: Advisory Board; Astra-Zeneca: Other: Advisory Board. Carrier:Bayer: Honoraria; Pfizer: Honoraria; BMS: Honoraria, Research Funding; Leo Pharma: Research Funding.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1237-1237 ◽  
Author(s):  
Deborah Y. Park ◽  
Shyam K. Poudel ◽  
Xuefei Jia ◽  
Mailey Lynn Wilks ◽  
Vicki Pinkava ◽  
...  

Abstract Background: Emerging data suggest that treatment of cancer-associated venous thromboembolism (VTE) with direct oral anticoagulants (DOACs) results in lower recurrence rate compared to low molecular weight heparins (LMWHs) at 6 months but with concern for increase in bleeding risks. The objective of this study was to determine occurrence of major bleeding as well as recurrent VTE events on treatment with DOACs or LMWHs in a cohort study. Methods: The cancer-associated thrombosis (CAT) clinic is a centralized service for care of cancer patients with suspected deep venous thrombosis (DVT) and/or pulmonary embolism (PE) established at the Tausig Cancer Institute of the Cleveland Clinic. We conducted a prospective cohort study of patients referred to this clinic between 8/2014 through 1/2018. The demographics, cancer types, VTE characteristics, treatment courses, and outcomes (VTE recurrence, major or clinically relevant nonmajor [CRNM] bleeding) were recorded for these patients. Standards of treatment at the CAT clinic shifted in late 2017 from use of LMWH, enoxaparin, to a DOAC, rivaroxaban for cancer-associated VTE. Current exclusion criteria for rivaroxaban use include recent active bleeding, GFR < 30 mL/min, severe hepatic impairment, thrombocytopenia (platelet count < 50,000), and/or expected malabsorption at the level of stomach or small bowel. For cancer patients considered at higher risk of bleeding, including patients with luminal gastrointestinal cancers with an intact primary; cancers at risk of bleeding from genitourinary tract, bladder or nephrostomy tubes; or patients with active mucosal abnormalities such as duodenal ulcers, gastritis/esophagitis or colitis, treatment with LMWHs is preferred. Major or CRNM bleeding was determined according to definitions outlined by the International Society on Thrombosis and Haemostasis. Results: The study population included 258 patients with acute VTE. Of these, 239 patients had DVT (93%), 34 had PE (14%), 15 had both (6.2%), and 3 had visceral vein thromboses (1.2%). The patients were 53% male with a median age of 65 ± 16 years. The most common cancer types were hematologic malignancies (19.5%, n = 50), primary brain tumors (11.2%, n = 29), lung (8.5%, n = 22), breast (7.0%, n = 18), and pancreatic cancers (6.6%, n = 17). Enoxaparin monotherapy was prescribed for 72.1% (n = 179 of 248) of patients. Other treatments included rivaroxaban (17.3%, n = 43), apixaban (0.8%, n = 2), warfarin (2.8%, n = 7), dalteparin (0.4%, n = 1), or no anticoagulation (3.2%, n = 8). Major bleeding occurred in 5% (n = 12 of 241) of patients treated with anticoagulation at 6 months of the initial event, including 5.0% (n = 9 of 179) of patients on enoxaparin and 4.7% (n = 2 of 43) of patients on rivaroxaban, and these differences were not significant (p > 0.95) (Figure 1). CRNM bleeding was observed in 16.2% (n = 29 of 179) of patients on enoxaparin and 11.6% (n = 5 of 43) of patients on rivaroxaban. The common cancer types for patients with major bleeding events included primary brain tumors (n = 4), genitourinary cancers (n = 2) and gastrointestinal cancers (n = 2) (Table 1). The 1-year incident rate of recurrent VTE was 11% for patients treated with enoxaparin and 9% for those treated with DOACs, and 2-year rate was 13% and 11%, respectively (Figure 2). Overall, there was no significant difference in the VTE recurrence rate calculated by the competing risk model between patients on enoxaparin compared to rivaroxaban (p = 0.19). Conclusions: Bleeding events of patients treated with enoxaparin was comparable to rivaroxaban for both major and CRNM bleeding events in this carefully selected real-world population. Patients receiving rivaroxaban reported a statistically insignificant but lower rate of recurrent VTE compared to those receiving enoxaparin. These findings support a recent change in ISTH guidance recommending rivaroxaban or edoxaban as initial treatment of cancer-associated VTE in selected patients. Disclosures Khorana: Sanofi: Consultancy; Bayer: Consultancy; Janssen: Consultancy; Pfizer: Consultancy.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 1135-1135
Author(s):  
Martin Gebel ◽  
Martin Prins ◽  
Anthonie WA Lensing

Abstract Background Several observational studies in patients at high risk of arterial vascular disease have shown that statin use is associated with a decreased risk of venous thromboembolism (VTE). A recent meta-analysis showed that the odds ratio for a first venous thromboembolic event for statin users was 0.89 (95% confidence interval [CI], 0.78–1.01) compared with non-users (Rahmini K, et al. PLoS Med 2012;9: e1001310 doi:10.1371/journal.pmed.1001310). Objective To evaluate the risk of recurrent VTE in patients with VTE treated with an anticoagulant (rivaroxaban or enoxaparin/vitamin K antagonist [VKA]) in relation to the concomitant use of statin therapy in the EINSTEIN-DVT and EINSTEIN-PE studies. Measurements Incidence densities of symptomatic recurrent VTE and major bleeding were expressed per 100 patient-years of exposure (or not) to statins. A Cox proportional hazards model was employed, with statin use as a time-dependent variable, for each treatment group (rivaroxaban vs enoxaparin/VKA) and adjusted for aspirin use, age, body mass index, cardiac disorders, gender, and creatinine clearance at baseline. Results A total of 1509 (18%) of the 8240 patients included in EINSTEIN-DVT and EINSTEIN-PE used statins during the course of the studies. Statin users were more likely to have cardiovascular disorders (31% vs 10%) and also used aspirin more often (26% vs 5%). During statin/rivaroxaban treatment, recurrent VTE occurred with an incidence of 2.0 per 100 patient-years versus 3.6 during non-statin-use (adjusted hazard ratio [HR], 0.62; 95% CI, 0.29–1.32). During statin/enoxaparin/VKA use, recurrent VTE occurred at an incidence of 3.2 per 100 patient-years versus 4.0 during non-statin-use (adjusted HR, 0.89; 95% CI, 0.47–1.69). Major bleeding during statin/rivaroxaban treatment occurred at an incidence of 2.2 per 100 patient-years versus 1.6 during non-statin-use (adjusted HR, 0.92; 95% CI, 0.43–1.98). During statin/enoxaparin/VKA treatment, the rate of major bleeding was 3.7 per 100 patient-years compared with 3.0 during non-statin-use (adjusted HR, 0.69; 95% CI, 0.36–1.32). Due to the adjustments in the Cox regression model the direction of these hazard ratios are in contrast to the crude comparison of rates by patient-years. This is largely because, in general, statin users are older and most of the major bleeding events in statin users occur in the ≥60 years age group. Limitations The study comprised a post-hoc analysis of data collected in two randomized clinical trials. Because the analyses were not a comparison of randomized groups, residual confounding is possible. Conclusions A modest, but not statistically significant, reduction in recurrent VTE was observed with statin use in patients treated for VTE. This reduction was similar in patients receiving enoxaparin/VKA or rivaroxaban therapy. Disclosures: Gebel: Bayer HealthCare AG: Employment, Equity Ownership. Prins:Bayer HealthCare: Consultancy, Honoraria, Research Funding; Boehringer Ingelheim: Consultancy, Honoraria, Research Funding; sanofi-aventis: Consultancy, Honoraria, Research Funding; GlaxoSmithKline: Consultancy, Honoraria, Research Funding; Daiichi Sankyo: Consultancy, Honoraria, Research Funding; LeoPharma: Consultancy, Honoraria, Research Funding; ThromboGenics: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria, Research Funding. Lensing:Bayer HealthCare: Employment.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 426-426 ◽  
Author(s):  
Yan Xu ◽  
Tara Gomes ◽  
Philip S. Wells ◽  
Ana Johnson ◽  
Michelle Sholzberg

Abstract Background: Major bleeding is the most serious complication of oral anticoagulation. Consensus criteria to define major bleeding have been established by the International Society for Thrombosis and Haemostasis (ISTH), Bleeding Academic Research Consortium (BARC) and Thrombolysis in Myocardial Infarction (TIMI). Significant variability exists across these definitions, and their agreement for identifying oral anticoagulant (OAC) related major bleeding is unknown. Furthermore, the association between each definition and mortality in cases of OAC bleeding has not been evaluated. We therefore, sought to evaluate the agreement of cases identified as major bleeding by the ISTH, BARC and TIMI definitions, and to assess associated in-hospital (emergency department or inpatient) and 30-day mortality of cases identified by these criteria. Methods: We used an existing dataset of individuals ≥66 years in Ontario, Canada, who presented to one of five tertiary care institutions with OAC related bleeding across three cities from 2010-2015. Detailed clinical data on consecutive episodes of OAC-associated bleeding were linked to population-based databases held at the Institute for Clinical Evaluative Sciences. We calculated Cohen's κ for agreement between the three major bleeding definitions, and used Pearson's χ2 to determine any differences in in-hospital and 30-day mortality for cases defined as major bleeding by ISTH, BARC and TIMI criteria. Results: We included 2,002 cases of OAC related bleeding in the analysis (460 on direct oral anticoagulants, 1,542 on warfarin). ISTH, BARC and TIMI major bleeding definitions were met in 75%, 77% and 29% of cases, respectively. 18% of cases did not meet criteria for major bleeding by any definition. Age, sex, CHA2DS2-VASc and HAS-BLED score, as well as proportion of chronic kidney disease were similar across ISTH-, BARC- and TIMI-defined cases. Over 9 in 10 cases of TIMI-defined major bleeding events involved an intracranial hemorrhage (94.4%), compared to 37% and 36% of cases identified by ISTH or BARC definitions respectively (p<0.001 across three groups). Agreement in case identification between ISTH and BARC was substantial (agreement 89%; Cohen's κ=0.69). On the other hand, agreement between TIMI and both ISTH (agreement 54%; Cohen's κ =0.24) and BARC (agreement 52%; Cohen's κ=0.21) were poor. The association between in-hospital mortality and TIMI-defined major bleeding was higher (29%) than that for ISTH and BARC (17% for both; p<0.001 for TIMI vs. ISTH and TIMI vs. BARC). The association with 30-day mortality showed a similar trend (30%, 18% and 18% for TIMI-, ISTH- and BARC- defined major bleeding events respectively; p<0.001 for TIMI vs. ISTH and TIMI vs. BARC). 6% of cases that were not categorized as major bleeding by ISTH or BARC definitions died within 30 days of hospital presentation, and this was 10% for cases not meeting criteria for TIMI major bleeding (10%, p=0.036 by Pearson's χ2). Conclusions: Among patients with OAC-associated bleeding, major bleeding events identified by ISTH and BARC criteria showed good agreement and similar prognostic utility. Meanwhile, TIMI criteria identified patients with higher clinical risk and subsequent mortality. Patients presenting with OAC-associated bleeding who did not fulfill ISTH or BARC major bleeding criteria had considerable risk of 30-day mortality and was even higher among those not meeting the TIMI criteria. Our findings suggest the need to refine current major bleeding definitions to identify additional patients at risk of death. Disclosures Wells: Bayer: Honoraria; BMS: Honoraria, Research Funding; Sanofi: Honoraria; Janssen: Honoraria. Sholzberg:Amgen: Research Funding; CSL Behring: Research Funding; Octapharma: Research Funding; Shire: Research Funding.


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