Decision-making for PCV in adults

Abstract

Thirteen-valent pneumococcal conjugate vaccine (PCV13) was licensed in adults to address the unmet medical need of vaccine-type community acquired pneumonia (CAP) and the limitations of previous plain-polysaccharide vaccines. Since then, some have questioned the utility of adult PCV13 use, arguing that: i) high PCV13 uptake in young children would provide indirect effects that, by themselves, would sufficiently protect unvaccinated adults and ii) no data describing the real-world effectiveness of PCV13 use in adults, especially with immunocompromising conditions, exist. Even in countries like the United States where PCV13 has been routinely recommended for all adults aged ≥ 65 years, the recommendation is contingent on a re-evaluation to determine if continued use is needed in the context of a mature PCV13 pediatric immunization program. Emerging evidence, however, suggests that i) a meaningful burden of PCV13-type pneumococcal pneumonia still persists in adults at increased risk for pneumococcal disease, despite indirect effects from long-standing pediatric PCV13 use, ii) adult PCV13 use is effective and has reduced pneumococcal CAP, even in the elderly and those with chronic medical or immunocompromising conditions - and disease could come back if PCV13 were removed, and iii) ethical and pragmatic vaccine policy considerations support continued adult PCV13 use in countries that have already introduced the vaccine (eg, disparities in adult PCV13 uptake, confusion stemming from removing a previously-recommended vaccine for a non-safety-related concern, and the reality that next-generation PCVs are only a few years away). Together, these findings suggest that continued PCV13 vaccination in adults is needed to control vaccine-type CAP.

Keywords: 13-valent pneumococcal conjugate vaccine (PCV13); adult; community-acquired pneumonia (CAP); policy; recommendation.

Figure 1.

Impact of excluding patients with healthcare-associated community-acquired pneumonia (HCAP) and immunocompromising conditions on incidence rates of hospitalized community-acquired pneumonia (per 100,000 person-years) in previously-conducted prospective surveillance studies.^25–27 EPIC = Etiology of Pneumonia in the Community; HCAP = healthcare-associated community-acquired pneumonia.

Figure 2.

Potential impact* of PCV13 use in US adults aged ≥ 65 years51. CAP = community-acquired pneumonia; US = United States; VE = vaccine effectiveness. *assumes 5% all-cause mortality each year and 100% vaccine uptake. ^†A significant effect on all-cause mortality was not demonstrated in Community Acquired Pneumonia Immunization Trial in Adults (CAPiTA).¹⁹

Figure 3.

Percentage of hospitalized CAP caused by PCV13 serotypes and percentage that have received PCV13 over time among adults aged ≥ 65 years, October 2013−September 2016 (n = 6347) ACIP = Advisory Committee on Immunization Practices. CAP = community-acquired pneumonia. PCV13 = 13-valent pneumococcal conjugate vaccine. *Y-axis does not go to 100%. ^†Recommendation for routine use of PCV13 for all adults aged ≥ 65 years.¹⁴

Figure 4.

Percentage of hospitalized CAP caused by PCV13 serotypes and percentage that have received PCV13 over time among adults aged 18 to 64 years with “at-risk” conditions, October 2013 to September 2016 (n = 2976) ACIP = Advisory Committee on Immunization Practices. CAP = community-acquired pneumonia. PCV13 = 13-valent pneumococcal conjugate vaccine. “At-risk” patients were defined as the absence of immunocompromising conditions but the presence of ≥ 1 chronic medical condition including: congestive heart failure, diabetes mellitus, chronic obstructive pulmonary disease (COPD), asthma, liver disease, or current alcoholism or smoking. *Y-axis does not go to 100%. ^†Recommendation for routine use of PCV13 for all adults aged ≥ 65 years.¹⁴