What are the recommendations for administering Prevnar 21 (Pneumococcal conjugate vaccine)?

Prevnar 21 (PCV21) Administration Recommendations

The Advisory Committee on Immunization Practices (ACIP) recommends PCV21 (CAPVAXIVE) as a single-dose vaccine option for all adults aged ≥65 years and adults aged 19-64 years with risk conditions who have not received a pneumococcal conjugate vaccine or whose vaccination history is unknown. 1, 2

Recommended Population Groups

• All adults aged ≥65 years should receive a pneumococcal conjugate vaccine (PCV), with PCV21 being one of the recommended options 1, 2
• Adults aged 19-64 years with certain risk conditions (immunocompromising conditions, chronic medical conditions) should receive a pneumococcal conjugate vaccine, with PCV21 being one of the recommended options 1
• As of October 2024, the ACIP expanded recommendations to include all adults aged ≥50 years, regardless of risk conditions 3

Administration Schedule Based on Prior Vaccination History

For PCV-Naïve Adults (no prior PCV or unknown history):

• Adults ≥65 years or adults 19-64 years with risk conditions: Administer a single dose of PCV21 1, 2
• Alternative options include PCV20 alone or PCV15 followed by PPSV23 (with at least 1-year interval for immunocompetent adults or at least 8-week interval for immunocompromised adults) 1, 2

For Previously Vaccinated Adults:

• Adults with prior PPSV23 only: Administer a single dose of PCV21 at least 1 year after the last PPSV23 dose 2
• Adults with prior PCV13 only: Administer a single dose of PCV21 at least 1 year after the PCV13 dose 2

Important Clinical Considerations

• PCV21 is administered as a single 0.5 mL intramuscular injection 4
• PCV21 contains 21 pneumococcal serotypes but notably does not include serotype 4, which is included in other pneumococcal vaccines (PCV15, PCV20, PPSV23) 1
• Serotype 4 has reemerged as a cause of invasive pneumococcal disease (IPD) in certain regions of the western United States, particularly affecting adults <65 years with risk conditions, substance abuse history, or experiencing homelessness 1
• PCV21 is contraindicated in persons with history of severe allergic reaction to any component of the vaccine or to diphtheria toxoid 4

Special Populations

• Immunocompromised adults: When using PCV15 followed by PPSV23, the recommended interval is at least 8 weeks between doses 2
• Adults with chronic medical conditions: When using PCV15 followed by PPSV23, the recommended interval is at least 1 year between doses 2
• Adults residing in nursing homes or long-term care facilities: May benefit more from PCV vaccination 2
• Adults with immunosenescence (age-related immune decline): Older adults experience increased risk of pneumococcal disease due to immunosenescence, comparable to younger adults with immunocompromising conditions 5

Clinical Impact and Disease Burden

• Before the COVID-19 pandemic, approximately 100,000 noninvasive pneumococcal pneumonia hospitalizations and 30,000 IPD cases occurred annually among U.S. adults 1
• Pneumococcal serotypes contained in PCV21 caused approximately 80% of IPD cases among adults with indications for vaccination during 2018-2022 1
• Adults with certain underlying conditions and those aged ≥65 years have experienced IPD case fatality ratios exceeding 10% 1
• Pneumococcal disease incidence is disproportionately higher in Black or African American adults than in non-Black adults 1

Potential Pitfalls and Caveats

• Be aware that PCV21 does not contain serotype 4, which has reemerged as a cause of IPD in certain regions of the western United States 1
• For patients at risk for serotype 4 IPD (adults <65 years with risk conditions, substance abuse history, or experiencing homelessness in western US regions), consider alternative pneumococcal vaccines that include serotype 4 1
• Ensure proper administration technique: shake the pre-filled syringe vigorously until the vaccine is a homogeneous white suspension and visually inspect for large particulate matter or discoloration prior to administration 4
• Appropriate medical treatment and supervision must be immediately available should an acute anaphylactic reaction occur following administration 4