Abstract:
Typhoid fever is a significant public health concern with most of the sufferers between 15 and 25 y of age in Nepal. We undertook this study to demonstrate Vi polysaccharide conjugated with diphtheria toxoid (Vi-DT) conjugate vaccine which is non-inferior to Typbar typhoid conjugate vaccine, a Vi polysaccharide vaccine conjugated with tetanus toxoid (Vi-TT) with a focus on the adult population from Dhulikhel Hospital which was one of the total four sites in Nepal. In this study, we assigned the eligible participants in 1:1:1:1 ratio by block randomization, and stratified into three age groups (6 months to less than 2 y, 2 y to less than 18 y, and 18 y to 45 y), allotted to Group A, B, C, and D. Group A, B, and C received 25 μg (0.5 mL) of Vi-DT study vaccine and participants in Group D received 25 μg (0.5 mL) Vi-TT vaccine. We descriptively analyzed safety in all the participants receiving one dose of the investigational vaccine. The anti-Vi-IgG seroconversion rate in Vi-DT recipients was 99.71% (97.5% CI 98.04-99.96; 344 of 345 participants) and 99.13% (94.27-99.87; 114 of 115) in Vi-TT recipients which indicates that Vi-DT vaccine is non-inferior to Vi-TT vaccine. In safety aspect, 16.81% of total subject had at least one solicited adverse reaction and 22.61% of the Vi-TT participants experienced at least one solicited adverse reaction with most of them being local adverse reactions. None of the enrolled participants reported serious adverse events. Our study shows that a single dose of the Vi-DT vaccine is immunogenic, safe to administer and non-inferior to the Vi-TT vaccine four weeks after vaccination.
摘要:
在尼泊尔,伤寒是一个重大的公共卫生问题,大多数患者年龄在15至25岁之间。我们进行了这项研究,以证明与白喉类毒素(Vi-DT)结合的Vi多糖结合疫苗不劣于Typbar伤寒结合疫苗,与破伤风类毒素(Vi-TT)结合的Vi多糖疫苗,重点是Dhulikhel医院的成年人口,该医院是尼泊尔总共四个地点之一。在这项研究中,我们通过区组随机化以1:1:1:1的比例分配符合条件的参与者,并分为三个年龄组(6个月至2岁以下,2y至18y以下,和18y至45y),分配给A组,B,C,D.A组,B,C接受25μg(0.5mL)Vi-DT研究疫苗,D组参与者接受25μg(0.5mL)Vi-TT疫苗。我们描述性地分析了所有接受一剂研究疫苗的参与者的安全性。Vi-DT受者的抗Vi-IgG血清转化率为99.71%(97.5%CI98.04-99.96;345名参与者中的344名)和Vi-TT受者的99.13%(94.27-99.87;115名114名),这表明Vi-DT疫苗不劣于Vi-TT疫苗。在安全方面,16.81%的总受试者至少有一次征求的不良反应,22.61%的Vi-TT参与者经历了至少一次征求的不良反应,其中大多数是局部不良反应。没有参与者报告严重不良事件。我们的研究表明,单剂量的Vi-DT疫苗具有免疫原性,接种后四周,给药安全且不劣于Vi-TT疫苗。