Ensitrelvir for Covid-19 Postexposure Prophylaxis in Household Contacts.

Previously, no antiviral agents were approved for postexposure prophylaxis in household contacts of patients with Covid-19.

此前，没有抗病毒药物被批准用于Covid-19患者的家庭接触者的暴露后预防。

Methods

In this double-blind, randomized, placebo-controlledtrial, we randomly assigned persons who were SARS-CoV-2-negative on local diagnostic testing but were household contacts of a patient with Covid-19 (the index patient) to receive either ensitrelvir (375 mg on day 1 and 125 mg daily on days 2 through 5) or placebo within 72 hours after symptom onset in the index patient.

在这项双盲、随机、安慰剂对照试验中，我们将那些在本地诊断测试中SARS-CoV-2呈阴性但与COVID-19患者（指数患者）有家庭接触的人随机分配，接受恩西特韦（第1天375毫克，第2天至第5天每天125毫克）或安慰剂治疗，在指数患者症状发作后72小时内开始服用。

The primary end point was Covid-19 (defined by a central laboratory-confirmed positive reverse-transcriptase-polymerase-chain-reaction assay and the presence of ≥1 of 14 prespecified Covid-19 symptoms lasting ≥48 hours) by day 10 in a household contact in the modified intention-to-treatpopulation (all the participants who underwent randomization, had a central laboratory-confirmed negative RT-PCR test for SARS-CoV-2 at baseline, and received at least one dose of the trial drug or placebo).

主要终点是通过在家庭接触者中定义的COVID-19（由中心实验室确认的阳性逆转录酶-聚合酶链反应检测和存在≥14种预设COVID-19症状中的至少一种，持续≥48小时），在修改意向治疗人群中到第10天为止（所有参与随机分组、在基线时有中心实验室确认的SARS-CoV-2阴性RT-PCR测试，并至少接受了一剂试验药物或安慰剂的参与者）。

Results

The modified intention-to-treatpopulation included 1030 participants in the ensitrelvir group and 1011 in the placebo group.

改良意向治疗人群包括1030名接受ensitrelvir治疗的参与者和1011名接受安慰剂治疗的参与者。

The mean age of the participants was 42.4 years; 71.1% had undergone randomization within 48 hours after symptom onset in the index patient, and 37.0% had at least one risk factor for severe Covid-19.

参与者的平均年龄为42.4岁；71.1%的参与者在首发病例症状出现后48小时内进行了随机分组，37.0%的参与者至少有一种严重Covid-19的风险因素。

The incidenceof Covid-19 was lower in the ensitrelvir group than in the placebo group (2.9% vs. 9.0%; risk ratio, 0.33; 95% confidence interval[CI], 0.22 to 0.49; P<0.001).

在恩西特韦组中，Covid-19的发生率低于安慰剂组（2.9%对比9.0%；风险比，0.33；95%置信区间[CI]，0.22至0.49；P<0.001）。

The incidenceof adverse events during the trial was similar in the two groups (15.1% in the ensitrelvir group and 15.5% in the placebo group), as was the incidenceof serious adverse events (0.2% in each group).

在试验期间，两组的不良事件发生率相似（恩西特韦组为15.1%，安慰剂组为15.5%），严重不良事件的发生率也相似（每组均为0.2%）。

No Covid-19-related hospitalizations or deaths were reported.

未报告与Covid-19相关的住院或死亡病例。

Conclusions

Ensitrelvir administered to household contacts of a patient with Covid-19 within 72 hours after symptom onset in the index patient was effective in preventing Covid-19 in the contacts.

在索引病例出现症状后的72小时内，对Covid-19患者的家庭接触者使用恩替韦尔（Ensitrelvir）能有效预防接触者感染Covid-19。

(Funded by Shionogi; SCORPIO-PEP Japan Registry for Clinical Trials number, jRCT2031230124; ClinicalTrials.gov number, NCT05897541.).

(由Shionogi资助; SCORPIO-PEP日本临床试验注册号，jRCT2031230124; ClinicalTrials.gov编号，NCT05897541。)