The optimal duration of anticoagulation after a first episode of unprovoked deep-vein thrombosis is uncertain. We aimed to assess the benefits and risks of an additional 18 months of treatment with warfarin versus placebo, after an initial 6 months of anticoagulation for a first unprovoked proximal deep-vein thrombosis. We conducted a multicenter, randomized, double-blind, controlled trial comparing an additional 18 months of warfarin with placebo in patients with a unprovoked proximal deep-vein thrombosis initially treated for 6 months (treatment period: 18 months; follow up after treatment period: 24 months). The primary outcome was the composite of recurrent venous thromboembolism or major bleeding at 18 months. Secondary outcomes were the composite at 42 months, as well as each component of the composite, and death unrelated to pulmonary embolism or major bleeding, at 18 and 42 months. All outcomes were centrally adjudicated. A total of 104 patients, enrolled between July 2007 and October 2013 were analyzed on an intention-to-treat basis; no patient was lost to follow-up. During the 18-month treatment period, the primary outcome occurred in none of the 50 patients in the warfarin group and in 16 out of 54 patients (cumulative risk, 29.6%) in the placebo group (hazard ratio, 0.03; 95% confidence interval: 0.01 to 0.09; P<0.001). During the entire 42-month study period, the composite outcome occurred in 14 patients (cumulative risk, 36.8%) in the warfarin group and 17 patients (cumulative risk, 31.5%) in the placebo group (hazard ratio, 0.72; 95% confidence interval: 0.35-1.46). In conclusion, after a first unprovoked proximal deep-vein thrombosis initially treated for 6 months, an additional 18 months of warfarin therapy reduced the composite of recurrent venous thrombosis and major bleeding compared to placebo. However, this benefit was not maintained after stopping anticoagulation. Clinical registration: this trial was registered at www.clinicaltrials.gov as #NCT00740493.
<b>BACKGROUND: </b>Although many patients with venous thromboembolism require extended treatment, it is uncertain whether it is better to use full- or lower-intensity anticoagulation therapy or aspirin.<b>METHODS: </b>In this randomized, double-blind, phase 3 study, we assigned 3396 patients with venous thromboembolism to receive either once-daily rivaroxaban (at doses of 20 mg or 10 mg) or 100 mg of aspirin. All the study patients had completed 6 to 12 months of anticoagulation therapy and were in equipoise regarding the need for continued anticoagulation. Study drugs were administered for up to 12 months. The primary efficacy outcome was symptomatic recurrent fatal or nonfatal venous thromboembolism, and the principal safety outcome was major bleeding.<b>RESULTS: </b>A total of 3365 patients were included in the intention-to-treat analyses (median treatment duration, 351 days). The primary efficacy outcome occurred in 17 of 1107 patients (1.5%) receiving 20 mg of rivaroxaban and in 13 of 1127 patients (1.2%) receiving 10 mg of rivaroxaban, as compared with 50 of 1131 patients (4.4%) receiving aspirin (hazard ratio for 20 mg of rivaroxaban vs. aspirin, 0.34; 95% confidence interval [CI], 0.20 to 0.59; hazard ratio for 10 mg of rivaroxaban vs. aspirin, 0.26; 95% CI, 0.14 to 0.47; P<0.001 for both comparisons). Rates of major bleeding were 0.5% in the group receiving 20 mg of rivaroxaban, 0.4% in the group receiving 10 mg of rivaroxaban, and 0.3% in the aspirin group; the rates of clinically relevant nonmajor bleeding were 2.7%, 2.0%, and 1.8%, respectively. The incidence of adverse events was similar in all three groups.<b>CONCLUSIONS: </b>Among patients with venous thromboembolism in equipoise for continued anticoagulation, the risk of a recurrent event was significantly lower with rivaroxaban at either a treatment dose (20 mg) or a prophylactic dose (10 mg) than with aspirin, without a significant increase in bleeding rates. (Funded by Bayer Pharmaceuticals; EINSTEIN CHOICE ClinicalTrials.gov number, NCT02064439 .).
BACKGROUND: Choosing short-term (3-6 months) or indefinite anticoagulation after a first unprovoked venous thromboembolic event (VTE) is a common and difficult clinical decision. The long-term absolute risk of recurrent VTE after a first unprovoked VTE, in all patients and sub-groups, is not well established, hindering decision making.
METHODS: We conducted a multi-center multi-national prospective cohort study in first unprovoked VTE patients to establish the long-term risk of recurrent VTE after short-term anticoagulation in first unprovoked VTE patients (and sub-groups).We followed patients for symptomatic suspected VTE off of OAT. Suspected recurrent VTE was investigated with reference to baseline imaging and then independently and blindly adjudicated.
FINDINGS: We recruited 663 participants between October, 2001 and March 2006 with the last follow-up in April 2014. During a mean 5.0 years of follow-up, 165/663 suspected VTE (in 408 patients) were adjudicated as recurrent VTE resulting in an annualized risk of recurrent VTE of 5.0% (95% CI: 4.2-5.8%) with a cumulative risk of 29.6% at 8 years. Men had a 7.6% (95% CI: 6.3-9.2%) annual risk of recurrent VTE. High risk women (2 or more HERDOO2 points; see text) had an annual risk of recurrent VTE of 5.9% (95% CI: 4.2-8.1%). Low risk women (1 or 0 HERDOO2 points) had 1.1% (95% CI: 0.6-2.0%) annual risk of recurrent VTE with a cumulative risk of 8.7% at 8 years.
INTERPRETATION: Men and high risk women with unprovoked VTE should be considered for long-term anticoagulant therapy given a high risk of recurrent VTE after long-term follow-up. Women with a low HERDOO2 score may be able to safely discontinue anticoagulants.
FUNDING: This study was funded by the Canadian Institutes of Health Research (Grant # MOP 64319) and Heart and Stroke Foundation of Ontario (Grant # NA 6771). Registered at www.clinicaltrials.gov identifier: NCT00261014.
Essentials Long-term recurrence risk of venous thromboembolism (VTE) is uncertain. We performed a prospective cohort study of 839 patients with first unprovoked VTE. VTE recurrence risk is high, particularly in men with proximal thrombosis or pulmonary embolism. Sex and VTE site determine the recurrence risk and should be considered for patient counseling.
SUMMARY: Background The long-term recurrence risk (ltRR) of venous thromboembolism (VTE) is uncertain. Objective To assess the ltRR of patients with first unprovoked VTE. Patients/methods Patients were classified into three categories: distal deep vein thrombosis (DVT), proximal DVT or pulmonary embolism (PE), that is, PE associated with DVT or isolated PE. Patients with major thrombophilia or antithrombotic therapy were excluded. The endpoint was recurrent symptomatic VTE. Results A total of 839 patients were followed for a median of 7.7 years. VTE recurred in 263 patients (31%). After 10 and 20 years, the cumulative ltRR was 32% (95% confidence interval [CI], 29-36) and 44% (95% CI, 38-49) with 3.9 (95% CI, 3.3-4.6) and 3.3 (95% CI, 2.7-4.0) events per 100 patient-years, respectively. The adjusted hazard ratio was 2.1 (95% CI, 1.4-3.2) and 2.1 (95% CI, 1.4-3.2) for patients with proximal DVT or PE compared with patients with distal DVT and was 2.1 (95% CI, 1.6-2.9) for men compared with women. At 10 years, 4.7 (95% CI, 3.8-5.8) events per 100 patient-years occurred in men with proximal DVT or PE, 2.4 (95% CI, 1.2-4.4) in men with distal DVT, 1.9 (95% CI, 1.2-2.8) in women with proximal DVT or PE and 0.9 (95% CI, 0.2-1.9) in women with distal DVT. Conclusion The ltRR of patients with first unprovoked VTE is high and dependent upon sex and VTE site.
BACKGROUND: There are few data on the relative efficacy and safety of direct oral anticoagulants, such as edoxaban, compared with vitamin K antagonists during extended therapy for venous thromboembolism. This analysis evaluates the risk-benefit of extended treatment for up to 12 months with edoxaban compared with warfarin among patients enrolled in the Hokusai-VTE study who continued therapy beyond 3 months.
METHODS: The Hokusai-VTE trial (NCT00986154) was a randomised, double-blind, event driven non-inferiority trial in 8292 patients comparing edoxaban with warfarin in the treatment of patients with acute venous thromboembolism. All patients were treated for at least 3 months and treatment was continued for up to 12 months. The outcomes at 12 months were documented in all patients irrespective of treatment duration. 3633 patients treated with edoxaban and 3594 treated with warfarin who completed 3 months of treatment were eligible for this analysis. The primary efficacy outcome was the incidence of adjudicated symptomatic recurrent venous thromboembolism evaluated for each of the time intervals of 3 months, greater than 3 months to 6 months, greater than 6 months to less than 12 months, and at 12 months, as well as the cumulative incidence occurring between 3 and 12 months. The principal safety outcome was the incidence of clinically relevant bleeding (composite of major or clinically relevant non-major bleeding). Both on-treatment and intention-to-treat analyses were done.
FINDINGS: In the on-treatment analysis, the incidence of recurrent venous thromboembolism at 3 months was 1·1% (0·8-1·4; 44 of 4118 patients) in the edoxaban-treated group versus 1·2% (0·9-1·6; 51 of 4122) in the warfarin-treated group; between greater than 3 months and 6 months, 0·7% (0·3-1·5; eight of 1076) versus 0·5% (0·2-1·1; five of 1084); between greater than 6 months and less than 12 months, 0·2% (0·0-0·8; two of 896) versus 0·8% (0·03-1·7; seven of 851); and at 12 months, <0·1% (0·0-0·3; one of 1661) versus 0·1% (0·0-0·4; two of 1659). In the on-treatment analysis, the cumulative incidence of recurrent venous thromboembolism between 3 and 12 months was 0·3% (95% CI 0·2-1·5; 11 of 3633 patients) in the edoxaban-treated group and 0·4% (0·2-1·7; 14 of 3594) in the warfarin-treated group (HR 0·78, 95% CI 0·36-1·72). The cumulative incidence of clinically relevant bleeding (major or non-major) between 3 and 12 months was 3·9% (95% CI 3·3-4·6; 143 of 3633 patients) in the edoxaban-treated group and 4·1% (3·5-4·8; 147 of 3594 patients) in the warfarin-treated group (HR 0·97, 95% CI 0·77-1·22); cumulative incidence of major bleeding was 0·3% (95% CI 0·2-0·5; 11 of 3633 patients) in the edoxaban-treated group and 0·7% (0·4-1·0; 24 of 3594 patients) in the warfarin-treated group (HR 0·45, 95% CI 0·22-0·92). Similar results were obtained in the intention-to-treat analysis.
INTERPRETATION: Extended treatment with edoxaban is effective and associated with less major bleeding than warfarin. Edoxaban once daily provides an attractive alternative to warfarin for patients with venous thromboembolism who require extended treatment for prevention of recurrent venous thromboembolism.
FUNDING: Daiichi Sankyo.
Patients with unprovoked venous thromboembolism (VTE) are at high risk for recurrence. Although rivaroxaban is effective for extended VTE treatment at a dose of 20 mg once daily, use of the 10 mg dose may further improve its benefit-to-risk ratio. Low-dose aspirin also reduces rates of recurrent VTE, but has not been compared with anticoagulant therapy. The EINSTEIN CHOICE study is a multicentre, randomised, double-blind, active-controlled, event-driven study comparing the efficacy and safety of two once daily doses of rivaroxaban (20 and 10 mg) with aspirin (100 mg daily) for the prevention of recurrent VTE in patients who completed 6-12 months of anticoagulant therapy for their index acute VTE event. All treatments will be given for 12 months. The primary efficacy objective is to determine whether both doses of rivaroxaban are superior to aspirin for the prevention of symptomatic recurrent VTE, while the principal safety outcome is the incidence of major bleeding. The trial is anticipated to enrol 2,850 patients from 230 sites in 31 countries over a period of 27 months. In conclusion, the EINSTEIN CHOICE study will provide new insights into the optimal antithrombotic strategy for extended VTE treatment by comparing two doses of rivaroxaban with aspirin (clinicaltrials.gov NCT02064439).
<b>Importance: </b>The optimal duration of anticoagulation after a first episode of unprovoked pulmonary embolism is uncertain.<b>OBJECTIVES: </b>To determine the benefits and harms of an additional 18-month treatment with warfarin vs placebo, after an initial 6-month nonrandomized treatment period on a vitamin K antagonist.<b>Design, Setting, and Participants: </b>Randomized, double-blind trial (treatment period, 18 months; median follow-up, 24 months); 371 adult patients who had experienced a first episode of symptomatic unprovoked pulmonary embolism (ie, with no major risk factor for thrombosis) and had been treated initially for 6 uninterrupted months with a vitamin K antagonist were randomized and followed up between July 2007 and September 2014 in 14 French centers.<b>INTERVENTIONS: </b>Warfarin or placebo for 18 months.<b>Main Outcomes and Measures: </b>The primary outcome was the composite of recurrent venous thromboembolism or major bleeding at 18 months after randomization. Secondary outcomes were the composite at 42 months (treatment period plus 24-month follow-up), as well as each component of the composite, and death unrelated to pulmonary embolism or major bleeding, at 18 and 42 months.<b>RESULTS: </b>After randomization, 4 patients were lost to follow-up, all after month 18, and 1 withdrew due to an adverse event. During the 18-month treatment period, the primary outcome occurred in 6 of 184 patients (3.3%) in the warfarin group and in 25 of 187 (13.5%) in the placebo group (hazard ratio [HR], 0.22; 95% CI, 0.09-0.55; P = .001). Recurrent venous thromboembolism occurred in 3 patients in the warfarin group and 25 patients in the placebo group (HR, 0.15; 95% CI, 0.05-0.43); major bleeding occurred in 4 patients in the warfarin group and in 1 patient in the placebo group (HR, 3.96; 95% CI, 0.44 to 35.89). During the 42-month entire study period (including the study treatment and follow-up periods), the composite outcome occurred in 33 patients (20.8%) in the warfarin group and in 42 (24.0%) in the placebo group (HR, 0.75; 95% CI, 0.47-1.18). Rates of recurrent venous thromboembolism, major bleeding, and unrelated death did not differ between groups.<b>Conclusions and Relevance: </b>Among patients with a first episode of unprovoked pulmonary embolism who received 6 months of anticoagulant treatment, an additional 18 months of treatment with warfarin reduced the composite outcome of recurrent venous thrombosis and major bleeding compared with placebo. However, benefit was not maintained after discontinuation of anticoagulation therapy.<b>Trial Registration: </b>clinicaltrials.gov Identifier: NCT00740883.
This is a multicenter, randomized, double-blind, event-driven, superiority study for efficacy.
Patients with confirmed symptomatic DVT (Deep Vein Thrombosis) or PE (Pulmonary embolism) who completed 6 or 12 months of treatment of anticoagulation are eligible for this trial
CONTEXTE: L'apixaban, un inhibiteur oral du facteur Xa qui peuvent être administrés selon un schéma simple, à dose fixe, peut être une option pour le traitement prolongé de la thromboembolie veineuse.
Méthodes: Dans cette étude randomisée, en double aveugle, nous avons comparé deux doses de apixaban (2,5 mg et 5 mg, deux fois par jour) à un placebo chez des patients présentant la maladie thromboembolique veineuse qui avaient terminé 6 à 12 mois de traitement anticoagulant et pour lesquels il était clinique équilibre quant à la poursuite ou l'arrêt du traitement anticoagulant. Les médicaments de l'étude ont été administrés pendant 12 mois.
Résultats: Un total de 2486 patients ont subi la randomisation, dont 2482 ont été inclus dans l'analyse en intention de traiter. Thromboembolie veineuse symptomatique récurrente ou la mort de thromboembolie veineuse ont eu lieu dans 73 des 829 patients (8,8%) qui recevaient un placebo, par rapport à 14 des 840 patients (1,7%) qui recevaient 2,5 mg d'apixaban (une différence de 7,2 pourcentage points, intervalle de confiance à 95% [IC]: 5,0 à 9,3) et 14 des 813 patients (1,7%) qui recevaient 5 mg d'apixaban (une différence de 7,0 points de pourcentage; CI, 04.09 à 09.01 95%) (P < 0,001 pour les deux comparaisons). Les taux de saignements majeurs étaient de 0,5% dans le groupe placebo, 0,2% dans le groupe apixaban 2,5 mg et de 0,1% dans le groupe apixaban 5 mg. Les taux de saignements de nonmajor cliniquement pertinente de 2,3% dans le groupe placebo, 3,0% dans le groupe apixaban 2,5 mg et de 4,2% dans le groupe apixaban 5 mg. Le taux de décès toutes causes confondues était de 1,7% dans le groupe placebo, contre 0,8% dans la 2.5 mg groupe apixaban et de 0,5% dans le groupe apixaban 5 mg.
CONCLUSIONS: anticoagulation prolongée avec l'apixaban à une dose de traitement (5 mg) ou une dose thromboprophylactique (2,5 mg) réduit le risque de thromboembolie veineuse récurrente, sans augmenter le taux de saignements majeurs. (Financé par Bristol-Myers Squibb et Pfizer; AMPLIFY-EXT nombre ClinicalTrials.gov, NCT00633893.).
The optimal duration of anticoagulation after a first episode of unprovoked deep-vein thrombosis is uncertain. We aimed to assess the benefits and risks of an additional 18 months of treatment with warfarin versus placebo, after an initial 6 months of anticoagulation for a first unprovoked proximal deep-vein thrombosis. We conducted a multicenter, randomized, double-blind, controlled trial comparing an additional 18 months of warfarin with placebo in patients with a unprovoked proximal deep-vein thrombosis initially treated for 6 months (treatment period: 18 months; follow up after treatment period: 24 months). The primary outcome was the composite of recurrent venous thromboembolism or major bleeding at 18 months. Secondary outcomes were the composite at 42 months, as well as each component of the composite, and death unrelated to pulmonary embolism or major bleeding, at 18 and 42 months. All outcomes were centrally adjudicated. A total of 104 patients, enrolled between July 2007 and October 2013 were analyzed on an intention-to-treat basis; no patient was lost to follow-up. During the 18-month treatment period, the primary outcome occurred in none of the 50 patients in the warfarin group and in 16 out of 54 patients (cumulative risk, 29.6%) in the placebo group (hazard ratio, 0.03; 95% confidence interval: 0.01 to 0.09; P<0.001). During the entire 42-month study period, the composite outcome occurred in 14 patients (cumulative risk, 36.8%) in the warfarin group and 17 patients (cumulative risk, 31.5%) in the placebo group (hazard ratio, 0.72; 95% confidence interval: 0.35-1.46). In conclusion, after a first unprovoked proximal deep-vein thrombosis initially treated for 6 months, an additional 18 months of warfarin therapy reduced the composite of recurrent venous thrombosis and major bleeding compared to placebo. However, this benefit was not maintained after stopping anticoagulation. Clinical registration: this trial was registered at www.clinicaltrials.gov as #NCT00740493.
