Center for Biostatistics in AIDS Research, Harvard T. H. Chan School of Public Health, Boston, Massachusetts.
Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland.
J Pediatric Infect Dis Soc. 2017 Sep 1;6(3):e69-e74. doi: 10.1093/jpids/piw094.
The US Advisory Committee on Immunization Practices recommends a booster dose of quadrivalent meningococcal conjugate vaccine (MCV4) after initial immunization for patients at high risk for meningococcal infection.
The International Maternal Pediatric Adolescents AIDS Clinical Trials (IMPAACT) P1065 trial evaluated the use of MCV4 in human immunodeficiency virus (HIV)-infected children and youth. The final step of this trial was an open-label study of an MCV4 booster dose 3.5 years after primary MCV4 immunization. Antibody titers were evaluated at the time of the booster vaccine and 1, 4, and 24 weeks after the booster. Immunogenicity was measured by rabbit serum bactericidal antibody (rSBA) against each meningococcal serogroup. Immunologic memory was defined as either seroprotection (rSBA titer ≥1:128) or a ≥4-fold increase 1 week after the booster dose. Primary response was defined as either a ≥4-fold response or seropositivity 4 weeks after the booster in the absence of immunologic memory. Adverse events were assessed for 4 weeks after the booster dose.
Of 174 participants with serology results at entry and 1 and 4 weeks later, the percentage with protective antibody levels at entry varied according to serogroup, ranging from a low of 26% for serogroup C to a high of 68% for serogroup A. A memory response to at least 1 serogroup occurred in 98% of the participants: 93% each for serogroups A and Y, 88% for serogroup C, and 94% for serogroup W-135; 83% had a memory response to all 4 serogroups. Overall, rates of any memory or primary response were ≥90% for all serogroups. No serious adverse events were encountered.
A booster dose of MCV4 elicited a memory response in 88% to 94% of previously immunized HIV-infected participants depending on serogroup, including those who lacked a protective titer level for that serogroup before booster vaccination.
美国免疫实施咨询委员会建议,对于有发生脑膜炎奈瑟菌感染风险的患者,在初始接种四价脑膜炎球菌结合疫苗(MCV4)后进行加强免疫。
国际母婴青少年艾滋病临床试验(IMPAACT)P1065 试验评估了 MCV4 在人类免疫缺陷病毒(HIV)感染儿童和青少年中的应用。该试验的最后一步是在初次接种 MCV4 3.5 年后进行 MCV4 加强免疫的开放性研究。在加强疫苗接种时以及加强疫苗接种后 1、4 和 24 周评估抗体滴度。用兔血清杀菌抗体(rSBA)针对每种脑膜炎奈瑟菌血清群评估免疫原性。免疫记忆定义为血清保护(rSBA 滴度≥1:128)或加强免疫后 1 周时增加≥4 倍。初次反应定义为加强免疫后 4 周内无免疫记忆时,rSBA 滴度增加≥4 倍或血清阳性。在加强免疫后 4 周内评估不良事件。
在 174 名有血清学结果的参与者中,有 174 名在进入研究时和 1 周和 4 周后进行了评估,根据血清群,进入时具有保护抗体水平的参与者百分比有所不同,血清群 C 的比例最低为 26%,血清群 A 的比例最高为 68%。至少对 1 个血清群产生记忆反应的参与者占 98%:血清群 A 和 Y 各占 93%,血清群 C 占 88%,血清群 W-135 占 94%;83%的参与者对所有 4 个血清群均有记忆反应。总体而言,对于所有血清群,任何记忆或初次反应的发生率均≥90%。未发生严重不良事件。
根据血清群的不同,MCV4 加强免疫在 88%至 94%的既往免疫的 HIV 感染参与者中引起了记忆反应,包括那些在加强疫苗接种前针对该血清群缺乏保护滴度的参与者。