<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 .).
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: Les patients qui ont eu un premier épisode de thrombose veineuse non provoquée ont un risque élevé de récidive après anticoagulants sont abandonnées. L'aspirine peut être efficace pour prévenir une récidive de la maladie thromboembolique veineuse.
MÉTHODES: Nous avons assigné au hasard 822 patients ayant terminé le traitement initial de l'anticoagulant après un premier épisode de thrombose veineuse non provoquée de recevoir l'aspirine, à une dose de 100 mg par jour, ou un placebo pendant 4 ans. Le critère principal était la récurrence de la maladie thromboembolique veineuse.
RÉSULTATS: Au cours d'une période de suivi médiane de 37,2 mois thromboembolie veineuse sont réapparus chez 73 des 411 patients du groupe placebo et chez 57 des 411 attribué à l'aspirine (un taux de 6,5% par an contre 4,8% par an; hazard ratio avec aspirine, 0,74, intervalle de confiance à 95% [IC], 0,52 à 1,05, p = 0,09). L'aspirine réduit le taux des deux résultats composites secondaires pré-spécifiés: le taux de thrombo-embolie veineuse, infarctus du myocarde, accident vasculaire cérébral ou cardiovasculaire décès était réduit de 34% (soit un taux de 8,0% par an avec placebo contre 5,2% par an avec de l'aspirine; rapport de risque avec de l'aspirine, 0,66, IC 95%, 0,48 à 0,92, p = 0,01) et le taux de thrombo-embolie veineuse, infarctus du myocarde, accident vasculaire cérébral, hémorragie majeure ou décès toutes causes confondues a été réduite de 33% (hazard ratio: 0,67 , IC 0,49 à ,91 95%, p = 0,01). Il n'y avait aucune différence entre les groupes significative dans les taux de majeurs ou cliniquement pertinente épisodes de saignement nonmajor (taux de 0,6% par an avec placebo contre 1,1% par an avec de l'aspirine, P = 0,22) ou d'événements indésirables graves.
CONCLUSIONS: Dans cette étude, l'aspirine, par rapport au placebo, n'a pas réduit significativement le taux de récidive de la maladie thromboembolique veineuse, mais a entraîné une réduction significative du taux d'accidents vasculaires majeurs, avec l'amélioration de bénéfice clinique net. Ces résultats corroborent preuve antérieure d'un bénéfice thérapeutique de l'aspirine quand il est administré à des patients après le traitement initial de l'anticoagulant pour un premier épisode de thrombose veineuse provocation. (Financé par Santé nationale et du Conseil de recherches médicales [Australie] et d'autres; Australian New Zealand essais cliniques numéro d'enregistrement, ACTRN12605000004662.).
CONTEXTE: Environ 20% des patients atteints de la maladie thromboembolique veineuse non provoquée ont une récidive dans les 2 ans après l'arrêt du traitement anticoagulant oral. Extension anticoagulation empêche les récidives, mais est associée à une augmentation des saignements. Le bénéfice de l'aspirine pour la prévention de la thromboembolie veineuse récurrente est inconnue.
Méthodes: Dans cette étude multicentrique, initiée par l'enquêteur, étude en double aveugle, les patients avec maladie thromboembolique veineuse première provocation qui avait terminé 6 à 18 mois de traitement par anticoagulants oraux ont été assignés au hasard à l'aspirine, 100 mg par jour, ou un placebo pendant 2 ans, avec la possibilité d'étendre le traitement à l'étude. Le critère principal d'efficacité était récurrence de la maladie thromboembolique veineuse et saignements majeurs était le critère principal de tolérance.
RÉSULTATS: thromboembolie veineuse récidivé dans 28 des 205 patients qui ont reçu de l'aspirine et dans 43 des 197 patients ayant reçu le placebo (6,6% vs 11,2% par an; hazard ratio 0,58, intervalle de confiance à 95% [IC], 0,36 au 0,93 ) (période d'étude médiane de 24,6 mois). Pendant une période médiane de traitement de 23,9 mois, 23 patients prenant de l'aspirine et 39 sous placebo avaient une récidive (5,9% contre 11,0% l'an; hazard ratio 0,55, IC 95%, 0,33 à 0,92). Un patient dans chaque groupe de traitement a eu un épisode hémorragique majeur. Les événements indésirables étaient similaires dans les deux groupes.
CONCLUSIONS: L'aspirine réduit le risque de récidive lorsqu'il est administré à des patients ayant la maladie thromboembolique veineuse non provoquée qui avaient abandonné le traitement anticoagulant, sans augmentation apparente du risque de saignement majeur. (Financé par l'Université de Pérouse et d'autres;. WARFASA nombre ClinicalTrials.gov, NCT00222677).
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.
METHODS:
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.
RESULTS:
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.
CONCLUSIONS:
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 .).
