CLINICAL TRIAL article

Front. Immunol.

Sec. Vaccines and Molecular Therapeutics

Volume 16 - 2025 | doi: 10.3389/fimmu.2025.1623611

Immunogenicity and safety study of 23-valent pneumococcal polysaccharide vaccine revaccination among elderly individuals aged 60-70 years in Shanghai, China

Provisionally accepted
Jing  QiuJing Qiu1Zhi  LiZhi Li1Fang  HuangFang Huang1Zhuoying  HuangZhuoying Huang1Xiufang  LiangXiufang Liang2Juan  LiJuan Li1Yuting  LiaoYuting Liao1Xiang  GuoXiang Guo1*Xiaodong  SunXiaodong Sun1
  • 1Shanghai Municipal Center for Disease Control and Prevention (SCDC), Shanghai, China
  • 2Yangpu District Center for Disease Control and Prevention, Shanghai, China

The final, formatted version of the article will be published soon.

Background: To understand the immunogenicity and safety of the 23-valent pneumococcal polysaccharide vaccine in elderly individuals aged 60-70 years in Shanghai after revaccination.Methods: A total of 330 elderly people aged 60-70 years were recruited to study the immunogenicity and safety of PPSV23 revaccination. The group with a history of PPSV23 vaccination and an interval of 5 years or more was selected as the revaccination group (n=220), and the group without any pneumococcal vaccine was selected as the first vaccination group (n=110).In terms of immunogenicity, the GMCs of all serotypes before and after immunization were 1.15-21.57 µg/ml and 1.62-33.19 µg/ml, respectively, in the revaccination group, and the GMCs of all serotypes after immunization were higher than those before immunization (P<0.0001). After immunization, the total GMI of antibodies in the revaccination group was lower than that in the first vaccination group [1.62(1.57, 1.67) vs 3.20(2.82, 3.57), P<0.0001], and the GMIs of all serotypes in the revaccination group were also lower than those in the first vaccination group [(1.40-1.92) vs (1.82-4.69), P<0.0001]. In terms of safety, no serious adverse events occurred during the study and all adverse events that occurred were mild or self-limiting. From 0-30 days after immunization, 7 patients in the revaccination group and 14 patients in the first vaccination group experienced adverse events, with incidence rates of 3.18% and 12.73%, respectively, which were lower in the revaccination group than in the first vaccination group (P=0.0008).Compared with those before vaccination, the antibody levels of elderly people aged 60-70 years in Shanghai who were inoculated with PPSV23 for 5 years or more tended to increase but were lower than those in the first vaccination group. The safety of revaccination with PPSV23 was favorable.Trial registration Registered January 2021 on the foreign website (http: //clinicaltrials. gov, NCT04701788) and on the domestic website (http://www. chictr. org. cn, ChiCTR2100042000).

Keywords: Elderly, Revaccination, 23-Valent pneumococcal polysaccharide vaccine, Immunogenicity, Safety

Received: 14 May 2025; Accepted: 01 Jul 2025.

Copyright: © 2025 Qiu, Li, Huang, Huang, Liang, Li, Liao, Guo and Sun. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence: Xiang Guo, Shanghai Municipal Center for Disease Control and Prevention (SCDC), Shanghai, China

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