PMS & Pharmacoepidemiology Department, Shionogi Pharmacovigilance Center Co, Ltd, Osaka, Japan.
Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan.
Clin Infect Dis. 2021 Jun 1;72(11):e859-e867. doi: 10.1093/cid/ciaa1622.
Baloxavir marboxil (baloxavir) is expected to reduce influenza transmission by rapid reduction of viral load. The incidence of household transmission was compared between index patients (IPs) treated with baloxavir and those treated with neuraminidase inhibitors.
Using a Japanese claims database, the first family members with influenza diagnosis during the 2018-2019 influenza season were identified as IPs, and the diagnosis date was designated day 1. According to the anti-influenza drug dispensed to the IP, their families were classified into the oral baloxavir group and 3 controls: oral oseltamivir group (a primary control), inhaled zanamivir group, and inhaled laninamivir group. A household transmission was defined as influenza diagnosed for any non-IP family members during days 3-8. The incidence of household transmission was compared between groups using a logistic regression model adjusting backgrounds of IPs.
The proportion of families with household transmission was 17.98% (15 226 of 84 672) in the baloxavir group and 24.16% (14 983 of 62 004) in the oseltamivir group. The covariate-adjusted odds ratio (oseltamivir/baloxavir) was 1.09 (95% confidence interval [95% CI], 1.05-1.12), which indicated significantly lower incidence in the baloxavir group. The adjusted odds ratios (controls/baloxavir) against zanamivir and laninamivir were 0.93 (95% CI, .89-.97) and 0.99 (95% CI, .96-1.02), respectively.
Baloxavir may contribute to reduction in household transmission compared with oseltamivir. In comparison between baloxavir and inhalants, a similar reduction was not shown and it might be due to unmeasured confounding by administration route differences.
巴洛沙韦（baloxavir）有望通过快速降低病毒载量来减少流感传播。比较了接受巴洛沙韦治疗和接受神经氨酸酶抑制剂治疗的指数患者（IP）之间的家庭传播发生率。
使用日本索赔数据库，确定了 2018-2019 流感季节中第一个被诊断患有流感的家庭成员为 IP，并将诊断日期指定为第 1 天。根据给予 IP 的抗流感药物，将其家庭分为口服巴洛沙韦组和 3 个对照组：口服奥司他韦组（主要对照组）、吸入扎那米韦组和吸入拉尼米韦组。家庭传播定义为任何非 IP 家庭成员在第 3-8 天期间被诊断出患有流感。使用调整 IP 背景的逻辑回归模型比较各组之间的家庭传播发生率。
在巴洛沙韦组中，家庭传播的比例为 17.98%（84672 例中的 15226 例），在奥司他韦组中为 24.16%（62004 例中的 14983 例）。调整后的比值比（奥司他韦/巴洛沙韦）为 1.09（95%置信区间[95%CI]，1.05-1.12），表明巴洛沙韦组的发病率显著降低。与扎那米韦和拉尼米韦相比，调整后的比值比（对照/巴洛沙韦）分别为 0.93（95%CI，0.89-0.97）和 0.99（95%CI，0.96-1.02）。
与奥司他韦相比，巴洛沙韦可能有助于减少家庭传播。与吸入剂相比，巴洛沙韦没有显示出类似的降低效果，这可能是由于给药途径差异导致的未测量混杂因素造成的。
