Department of Internal and Cardiovascular Medicine-Stroke Unit, University of Perugia, Perugia, Italy.
N Engl J Med. 2013 Feb 21;368(8):699-708. doi: 10.1056/NEJMoa1207541. Epub 2012 Dec 8.
Apixaban, an oral factor Xa inhibitor that can be administered in a simple, fixed-dose regimen, may be an option for the extended treatment of venous thromboembolism.
In this randomized, double-blind study, we compared two doses of apixaban (2.5 mg and 5 mg, twice daily) with placebo in patients with venous thromboembolism who had completed 6 to 12 months of anticoagulation therapy and for whom there was clinical equipoise regarding the continuation or cessation of anticoagulation therapy. The study drugs were administered for 12 months.
A total of 2486 patients underwent randomization, of whom 2482 were included in the intention-to-treat analyses. Symptomatic recurrent venous thromboembolism or death from venous thromboembolism occurred in 73 of the 829 patients (8.8%) who were receiving placebo, as compared with 14 of the 840 patients (1.7%) who were receiving 2.5 mg of apixaban (a difference of 7.2 percentage points; 95% confidence interval [CI], 5.0 to 9.3) and 14 of the 813 patients (1.7%) who were receiving 5 mg of apixaban (a difference of 7.0 percentage points; 95% CI, 4.9 to 9.1) (P<0.001 for both comparisons). The rates of major bleeding were 0.5% in the placebo group, 0.2% in the 2.5-mg apixaban group, and 0.1% in the 5-mg apixaban group. The rates of clinically relevant nonmajor bleeding were 2.3% in the placebo group, 3.0% in the 2.5-mg apixaban group, and 4.2% in the 5-mg apixaban group. The rate of death from any cause was 1.7% in the placebo group, as compared with 0.8% in the 2.5-mg apixaban group and 0.5% in the 5-mg apixaban group.
Extended anticoagulation with apixaban at either a treatment dose (5 mg) or a thromboprophylactic dose (2.5 mg) reduced the risk of recurrent venous thromboembolism without increasing the rate of major bleeding. (Funded by Bristol-Myers Squibb and Pfizer; AMPLIFY-EXT ClinicalTrials.gov number, NCT00633893.).
阿哌沙班是一种可口服的 Xa 因子抑制剂，可采用简单的固定剂量方案给药，可能是静脉血栓栓塞症延长治疗的选择。
在这项随机、双盲研究中，我们比较了阿哌沙班（2.5mg 和 5mg，每日两次）两种剂量与安慰剂在完成 6-12 个月抗凝治疗的静脉血栓栓塞患者中的疗效，对于继续或停止抗凝治疗存在临床平衡。研究药物治疗 12 个月。
共有 2486 名患者接受了随机分组，其中 2482 名患者被纳入意向治疗分析。在接受安慰剂的 829 名患者中，有 73 名（8.8%）发生症状性复发性静脉血栓栓塞或静脉血栓栓塞死亡，而接受 2.5mg 阿哌沙班的 840 名患者中有 14 名（1.7%）（差异为 7.2 个百分点；95%置信区间[CI]，5.0 至 9.3）和接受 5mg 阿哌沙班的 813 名患者中有 14 名（1.7%）（差异为 7.0 个百分点；95%置信区间[CI]，4.9 至 9.1）（均<0.001）。安慰剂组大出血发生率为 0.5%，2.5mg 阿哌沙班组为 0.2%，5mg 阿哌沙班组为 0.1%。临床相关非大出血发生率安慰剂组为 2.3%，2.5mg 阿哌沙班组为 3.0%，5mg 阿哌沙班组为 4.2%。安慰剂组因任何原因导致的死亡率为 1.7%，而 2.5mg 阿哌沙班组为 0.8%，5mg 阿哌沙班组为 0.5%。
阿哌沙班的抗凝治疗剂量（5mg）或预防剂量（2.5mg）可降低复发性静脉血栓栓塞的风险，而不增加大出血的发生率。（由 Bristol-Myers Squibb 和 Pfizer 资助；AMPLIFY-EXT 临床试验.gov 编号，NCT00633893）。
