Pfizer Inc, Collegeville, PA, USA.
Vaccine. 2013 Oct 1;31(42):4765-74. doi: 10.1016/j.vaccine.2013.08.009. Epub 2013 Aug 16.
The 7-valent pneumococcal conjugate vaccine (PCV7) has demonstrated effectiveness against pneumococcal illnesses when administered as 3 infant doses plus a toddler dose (3+1 schedule) or as an abbreviated schedule of 2 infant doses plus a toddler dose (2+1 schedule). The 13-valent pneumococcal conjugate vaccine (PCV13) is approved and World Health Organization-prequalified for administration in a 2+1 schedule when used as part of routine immunization programs.
To summarize immunologic responses elicited by PCV13 administered in a 2+1 schedule and following 2 doses in a 3+1 schedule.
Studies were double-blind, randomized, active-controlled, multicenter studies except the Mexico study (open-label, single-arm). In 2+1 studies, PCV13 was administered at 2, 4, and 12 (UK) or 3, 5, and 11 (Italy) months. In 3+1 studies (Spain and Mexico), assessment was made postdose 2 of the primary series (2, 4, and 6 months). The primary immunogenicity endpoint was the proportion of participants achieving serotype-specific antipolysaccharide immunoglobulin (Ig)G concentrations ≥ 0.35μg/mL (i.e., responders) 1 month postdose 2. Pneumococcal IgG geometric mean concentrations (GMCs), opsonophagocytic activity (OPA), and concomitant vaccine responses were assessed.
PCV13 and PCV7 elicited comparable immune responses for the 7 common serotypes after 2 infant doses. The proportion of PCV13 responders postdose 2 was >85% for most of the 7 common and 6 additional serotypes, except common serotypes 6B (27.9-81.4%) and 23F (55.8-77.5%) and additional serotypes 3 (73.8-96.9%) and 6A (79.2-94.4%). Serotypes 6B and 23F elicited lower IgG GMCs postdose 2 compared with other serotypes; all serotypes demonstrated boosting posttoddler dose. All serotypes demonstrated functional activity; >95% of participants achieved OPA levels ≥ 1:8 postdose 2. Concomitant vaccine responses were similar between PCV13 and PCV7 groups.
Immune responses elicited by PCV13 following 2 infant doses support transition from PCV7 to PCV13 in countries using a 2+1 schedule.
当 7 价肺炎球菌结合疫苗（PCV7）以 3 剂婴儿剂量加 1 剂幼儿剂量（3+1 计划）或 2 剂婴儿剂量加 1 剂幼儿剂量（2+1 计划）的形式进行接种时，已证明其对肺炎球菌疾病有效。13 价肺炎球菌结合疫苗（PCV13）已获准用于常规免疫接种计划，并在作为该计划一部分使用时获得了世界卫生组织的资格认证，可以采用 2+1 计划进行接种。
总结采用 2+1 计划接种 PCV13 后以及采用 3+1 计划接种 2 剂后的免疫应答情况。
这些研究均为双盲、随机、主动对照、多中心研究，但墨西哥的研究除外（开放性、单臂）。在 2+1 研究中，PCV13 在 2、4 和 12 个月（英国）或 3、5 和 11 个月（意大利）时接种。在 3+1 研究（西班牙和墨西哥）中，在主要系列的第 2 剂后（2、4 和 6 个月）进行评估。主要免疫学终点是在第 2 剂后 1 个月时达到血清型特异性抗多糖免疫球蛋白（IgG）浓度≥0.35μg/mL（即应答者）的参与者比例。评估肺炎球菌 IgG 几何平均浓度（GMC）、调理吞噬活性（OPA）和伴随疫苗应答情况。
在接种 2 剂婴儿剂量后，PCV13 和 PCV7 对 7 种常见血清型产生了相似的免疫应答。对于大多数 7 种常见血清型和 6 种额外血清型，除了常见血清型 6B（27.9-81.4%）和 23F（55.8-77.5%）以及额外血清型 3（73.8-96.9%）和 6A（79.2-94.4%）外，PCV13 第 2 剂后的应答者比例>85%。与其他血清型相比，血清型 6B 和 23F 在第 2 剂后 IgG GMC 较低；所有血清型在幼儿剂量后均表现出增强。所有血清型均表现出功能活性；在第 2 剂后，超过 95%的参与者的 OPA 水平≥1:8。PCV13 组和 PCV7 组的伴随疫苗应答相似。
在接种 2 剂婴儿剂量后，PCV13 产生的免疫应答支持在采用 2+1 计划的国家从 PCV7 过渡到 PCV13。
