A群C群脑膜炎球菌多糖结合疫苗在已完成基础免疫的18月龄儿童中加强免疫的安全性和免疫原性

Safety and immunogenicity of booster vaccination with group A and C meningococcal polysaccharide conjugate vaccine among 18-month-old children who had received primary vaccination

目的评价儿童A群C群脑膜炎球菌多糖结合疫苗(Group A and C meningococcal polysaccharide conjugate vaccine,MPCV-AC)加强免疫的安全性和免疫原性。方法在前期完成MPCV-AC基础免疫Ⅲ期临床试验的受试者中,选择已于3月龄开始接种3剂MPCV-AC(A组)和已于6-11月龄开始接种2剂MPCV-AC(B组)的儿童,于18月龄时加强接种1剂MPCV-AC,观察接种后0-30d不良反应和6个月内严重不良反应,检测接种前后血清A群和C群脑膜炎奈瑟菌(Neisseria meningitidis,Nm)杀菌抗体,分析不良反应发生率、抗体阳性率和几何平均滴度(Geometric mean titer,GMT)。结果A组和B组受试者MPCV-AC加强免疫后不良反应发生率分别为22.5%(27/120)、25.8%(31/120),未发生4级不良反应和与疫苗接种有关的严重不良事件。A组受试者加强免疫后vs加强免疫前A群、C群Nm抗体阳性率分别为100%(112/112)vs 19.33%(23/119)、99.11%(111/112)vs 23.53%(28/119),GMT(1:)分别为877.21 vs 2.34、855.77 vs 2.25;B组受试者加强免疫后vs加强免疫前A群、C群Nm抗体阳性率分别为100%(112/112)vs 51.67%(62/120)、96.43%(108/112)vs 45.00%(54/120),GMT(1:)分别为466.61 vs 9.51、298.84 vs 5.31。结论完成MPCV-AC基础免疫的婴儿于18月龄加强免疫显示良好的安全性和免疫原性。

Objective To evaluate the safety and immunogenicity of group A and C meningococcal polysaccharide conjugate vaccine(MPCV-AC)after booster vaccination.Methods From subjects who had completed a phase Ⅲ clinical trial of MPCV-AC primary vaccination,we enrolled children who had received 3 doses of MPCV-AC starting at 3 months of age(group A)and children who had received 2 doses of MPCV-AC starting at 6-11 months of age(group B).Children in both groups received one booster dose of MPCV-AC at 18 months of age.We observed for adverse reactions within 0-30 days and serious adverse reactions within 6 months after vaccination.We detected serogroup A and serogroup C Neisseria meningitidis(Nm)serum bactericidal antibody titers before and after booster-dose vaccination to determine positivity rates and geometric mean titers(GMTs).Results Incidences of adverse reactions in group A and group B after MPCV-AC booster vaccination were 22.5%(27/120)and 25.8%(31/120),respectively,with no grade 4 adverse reactions and no vaccine-related serious adverse reactions.Among subjects in group A,positivity rates of group A and C Nm antibodies after vs before booster vaccination were 100%(112/112)vs 19.33%(23/119)and 99.11%(111/112)vs 23.53%(28/119),with GMTs(1:)being 877.21 vs 2.34 and 855.77 vs 2.25.Among subjects in group B,positivity rates of group A and C Nm antibodies after vs before booster vaccination were 100%(112/112)vs 51.67%(62/120)and 96.43%(108/112)vs 45.00%(54/120),with GMTs(1:)being 466.61 vs 9.51 and 298.84 vs 5.31.Conclusions MPCV-AC booster vaccination at 18 months of children who had received primary MPCV-AC vaccination during infancy had good safety and immunogenicity profiles.