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Review
. 2026 Dec;22(1):2616144.
doi: 10.1080/21645515.2026.2616144. Epub 2026 Feb 9.

An overview of the clinical development of the 20-valent pneumococcal conjugate vaccine in adults

Affiliations
Review

An overview of the clinical development of the 20-valent pneumococcal conjugate vaccine in adults

Kathleen McElwee et al. Hum Vaccin Immunother. 2026 Dec.

Abstract

The 20-valent pneumococcal conjugate vaccine (PCV20) was developed to expand protection against vaccine-preventable disease caused by Streptococcus pneumoniae beyond the 13-valent pneumococcal conjugate vaccine (PCV13). This review summarizes the adult clinical development program of PCV20. Across studies, the safety profile of PCV20 was acceptable and similar to that of PCV13 and the 23-valent pneumococcal polysaccharide vaccine (PPSV23). Pivotal noninferiority comparisons of serotype-specific opsonophagocytic activity responses (PCV20 to PCV13 for the 13 matched serotypes; PCV20 to PPSV23 for the 7 additional serotypes) were conducted in pneumococcal vaccine‒naive ≥60-y-old adults to infer efficacy. Immunobridging of PCV20 responses to adults 60-64 y of age supports PCV20 use in adults 18 through 59 y of age, including those at increased risk of pneumococcal disease. Additionally, PCV20 elicited functional responses to all 20 vaccine serotypes in adults ≥65 y old who were previously vaccinated with PCV13 and/or PPSV23.

Keywords: 20-valent pneumococcal conjugate vaccine; Adults; Streptococcus pneumoniae; clinical trials; immunogenicity; safety.

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Conflict of interest statement

All authors are current or former Pfizer employees and may hold stock and/or stock options.

Figures

Figure 1.
Figure 1.
Study designs of phase 3 trials: the pivotal comparison study (A), the lot consistency study (B), and the study in adults with prior pneumococcal vaccine (C).
Figure 2.
Figure 2.
Pneumococcal OPA geometric mean titers and geometric mean ratios (95% CIs) for the 20 vaccine serotypes 1 month after vaccination: (A) pivotal trial in participants ≥60 years of age and (B) post hoc analysis of participants ≥65 y of age.

References

    1. Drijkoningen JJ, Rohde GG.. Pneumococcal infection in adults: burden of disease. Clin Microbiol Infect. 2014;20(suppl 5):45–14. doi: 10.1111/1469-0691.12461. - DOI - PubMed
    1. Ikuta KS, Swetschinski LR, Robles Aguilar G, Sharara F, Mestrovic T, Gray AP, Davis Weaver N, Wool EE, Han C, Gershberg Hayoon A, et al. Global mortality associated with 33 bacterial pathogens in 2019: a systematic analysis for the Global Burden of Disease Study 2019. Lancet. 2022;400(10369):2221–2248. doi: 10.1016/S0140-6736(22)02185-7. - DOI - PMC - PubMed
    1. Ganaie F, Saad JS, McGee L, van Tonder AJ, Bentley SD, Lo SW, Gladstone RA, Turner P, Keenan JD, Breiman RF, et al. A new pneumococcal capsule type, 10D, is the 100th serotype and has a large cps fragment from an oral Streptococcus. mBio. 2020;11(3):e00937–00920. doi: 10.1128/mBio.00937-20. - DOI - PMC - PubMed
    1. Geno KA, Gilbert GL, Song JY, Skovsted IC, Klugman KP, Jones C, Konradsen HB, Nahm MH. Pneumococcal capsules and their types: past, present, and future. Clin Microbiol Rev. 2015;28(3):871–899. doi: 10.1128/CMR.00024-15. - DOI - PMC - PubMed
    1. Wang Y, Li J, Wang Y, Gu W, Zhu F. Effectiveness and practical uses of 23-valent pneumococcal polysaccharide vaccine in healthy and special populations. Hum Vaccin Immunother. 2018;14(4):1003–1012. doi: 10.1080/21645515.2017.1409316. - DOI - PMC - PubMed

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