BACKGROUND The optimal duration of anticoagulation therapy for patients with cancer and acute low-risk pulmonary embolism (PE) is clinically relevant, but evidence is lacking. Prolonged anticoagulation therapy could have a potential benefit for prevention of thrombotic events; however, it could also increase the risk of bleeding. METHODS In a multicenter, open-label, adjudicator-blinded, randomized clinical trial at 32 institutions in Japan, we randomly assigned patients with cancer and acute low-risk PE of the simplified version of the Pulmonary Embolism Severity Index score of 1, in a 1:1 ratio, to receive either an 18-month or a 6-month rivaroxaban treatment. The primary end point was recurrent venous thromboembolism (VTE) at 18 months. The major secondary end point was major bleeding at 18 months according to the criteria of the International Society on Thrombosis and Hemostasis. The primary hypothesis was that an 18-month treatment was superior to a 6-month treatment in terms of the primary end point. RESULTS From February 2021 to March 2023, 179 patients were randomized, and after the exclusion of one patient who withdrew consent, 178 were included in the intention-to-treat population: 89 patients in the 18-month rivaroxaban group and 89 in the 6-month rivaroxaban group. The mean age was 65.7 years; 47% of the patients were men, and 12% had symptoms of PE at baseline. The primary end point of recurrent VTE occurred in 5 of the 89 patients (5.6%) in the 18-month rivaroxaban group and in 17 of the 89 (19.1%) in the 6-month rivaroxaban group (odds ratio, 0.25 [95% CI, 0.09-0.72]; P=0.01). Among 22 recurrent VTE, 5 patients presented with a symptomatic recurrent VTE; recurrent PE occurred in 11 patients, including 2 with main and 4 with lobar PEs; and recurrent deep vein thrombosis was seen in 11 patients, including 3 with proximal deep vein thromboses. The major secondary end point of major bleeding occurred in 7 of the 89 patients (7.8 %) in the 18-month rivaroxaban group and in 5 of the 89 patients (5.6%) in the 6-month rivaroxaban group (odds ratio, 1.43 [95% CI, 0.44-4.70]; P=0.55). CONCLUSIONS In patients with cancer and acute low-risk PE of the simplified version of the Pulmonary Embolism Severity Index score of 1, the 18-month rivaroxaban treatment was superior to the 6-month rivaroxaban treatment with respect to recurrent VTE events.

中文翻译：

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癌症和急性低危肺栓塞患者利伐沙班 18 个月与 6 个月：一项开放标签、多中心、随机临床试验（ONCO PE 试验）。


背景 癌症合并急性低危肺栓塞 （PE） 患者抗凝治疗的最佳持续时间具有临床相关性，但缺乏证据。长期抗凝治疗可能对预防血栓形成事件有潜在益处;但是，它也可能增加出血的风险。方法 在日本 32 个机构进行的一项多中心、开放标签、裁判者盲法、随机临床试验中，我们以 1：1 的比例随机分配肺栓塞严重程度指数评分简化版 1 分的癌症和急性低危 PE 患者接受 18 个月或 6 个月的利伐沙班治疗。主要终点是 18 个月时的复发性静脉血栓栓塞 （VTE）。根据国际血栓形成和止血学会的标准，主要次要终点是 18 个月时的大出血。主要假设是 18 个月的治疗在主要终点方面优于 6 个月的治疗。结果 从 2021 年 2 月到 2023年3月，随机分配了 179 例患者，在排除了 1 例撤回同意的患者后，意向治疗人群中纳入了 178 例患者：18 个月利伐沙班组 89 例患者，6 个月利伐沙班组 89 例患者。平均年龄为 65.7 岁;47% 的患者为男性，12% 的患者在基线时有 PE 症状。复发性 VTE 的主要终点发生在 18 个月利伐沙班组的 89 例患者中有 5 例 （5.6%），6 个月利伐沙班组 89 例患者中有 17 例 （19.1%） 发生（比值比，0.25 [95% CI，0.09-0.72];P=0.01）。 在 22 例复发性 VTE 中，5 例患者表现为有症状的复发性 VTE;复发性 PE 发生于 11 例患者，其中 2 例为主性 PE，4 例为肺叶 PE;11 例患者出现复发性深静脉血栓形成，其中 3 例近端深静脉血栓形成。18 个月利伐沙班组 89 例患者中有 7 例 （7.8%） 发生大出血的主要继发性终点，6 个月利伐沙班组 89 例患者中有 5 例 （5.6%） 发生（比值比，1.43 [95% CI，0.44-4.70];P=0.55）。结论 在肺栓塞严重程度指数评分简化版 1 的癌症和急性低危 PE 患者中，18 个月的利伐沙班治疗在复发性 VTE 事件方面优于 6 个月的利伐沙班治疗。