From the Guidelines
A single dose of Pneumococcal Conjugate Vaccine (PCV) 21 is effective for adults aged ≥18 years, as licensed by the Food and Drug Administration on June 17,2024, and recommended by the Advisory Committee on Immunization Practices (ACIP) 1. The effectiveness of PCV21 is based on its immunogenicity, safety, and resource use, which were considered by ACIP in their recommendations for its use in adults. Key points to consider when administering PCV21 include:
- PCV21 is licensed for use in persons aged ≥18 years 1
- It adds eight new serotypes not contained in other licensed vaccines, providing broader protection against Streptococcus pneumoniae bacteria
- The ACIP recommends receipt of a pneumococcal conjugate vaccine, such as PCV21, by all adults aged ≥65 years, as well as those aged 19–64 years with a risk condition who have not received PCV or whose vaccination history is unknown 1 The use of PCV21 as a single dose for adults is supported by the latest evidence, highlighting its importance in preventing infections caused by Streptococcus pneumoniae bacteria, which can lead to serious conditions like pneumonia, meningitis, and bloodstream infections.
From the Research
Effectiveness of Pneumococcal Conjugate Vaccine (PCV) 21
- The effectiveness of a single dose of PCV21 is supported by recent recommendations from the Advisory Committee on Immunization Practices (ACIP) 2.
- According to the ACIP, a single dose of PCV is recommended for all PCV-naïve adults aged ≥50 years, which may include PCV21 2.
- However, there is limited direct evidence on the effectiveness of a single dose of PCV21, as most studies have focused on PCV13 or other valencies.
- A study on PCV13 found that it induces a greater functional immune response than 23-valent pneumococcal polysaccharide vaccine (PPSV23) for the majority of serotypes covered by PCV13 3.
- Another study compared PCV13 with PPSV23 in adults 70 years and older and found that PCV13 was significantly more immunogenic than PPSV23 for most of the common serotypes and for serotype 6A 4.
Comparison with Other Vaccines
- PCV13 has been shown to be more immunogenic than PPSV23 in several studies 4, 3.
- The immune response to PCV13 was found to be generally greater in adults 50-59 years of age compared to adults 60-64 years of age 3.
- A systematic review of PCV dosing schedules found that various schedules, including 2+1,3+0, and 3+1, can be effective in preventing vaccine-type invasive pneumococcal disease among young children 5.
Considerations for Older Adults
- The use of PCVs in older adults has been debated, with some studies suggesting that PCV vaccination of children has reduced the incidence of conjugate vaccine-serotype disease in older adults, making PCV vaccination of older adults less necessary 6.
- However, the ACIP recommends a single dose of PCV for all PCV-naïve adults aged ≥50 years, which may include older adults 2.