What is the difference between Prevnar 20 (Pneumococcal conjugate vaccine) and other pneumococcal vaccines?

Differences Between Prevnar 20 and Prevnar 21 (CAPVAXIVE) Pneumococcal Vaccines

The primary difference between Prevnar 20 (PCV20) and Prevnar 21 (PCV21/CAPVAXIVE) is that PCV21 contains one additional serotype and has a different serotype composition compared to PCV20, with PCV21 being the most recently FDA-approved pneumococcal conjugate vaccine (June 2024) for adults aged ≥18 years. 1

Key Differences in Serotype Coverage

• PCV20 (Prevnar 20) contains 20 pneumococcal serotypes, building upon the original 13 serotypes in PCV13 (Prevnar 13) with 7 additional serotypes 1
• PCV21 (CAPVAXIVE) contains 21 serotypes but has a different composition - it does not contain certain serotypes present in other licensed vaccines but adds eight new serotypes 1
• The serotype differences are clinically significant as they target different strains of Streptococcus pneumoniae that cause invasive pneumococcal disease 1

Manufacturer Information

• PCV20 (Prevnar 20/Apexxnar) is manufactured by Pfizer/Wyeth Pharmaceuticals 1, 2
• PCV21 (CAPVAXIVE) is manufactured by Merck Sharp & Dohme, LLC 1

FDA Approval Status

• PCV20 was approved for adults in 2021 and received pediatric approval in April 2023 for individuals 6 weeks to 17 years of age 3, 4
• PCV21 was more recently approved by the FDA on June 17,2024, for use in persons aged ≥18 years 1
• Both vaccines are part of the ACIP recommendations for pneumococcal vaccination in adults 1, 5

Clinical Considerations

• Both vaccines are pneumococcal conjugate vaccines (PCVs), which provide better immunogenicity than polysaccharide vaccines by generating T-cell dependent immune responses 1
• PCVs induce memory B-cells, providing longer-lasting immunity compared to polysaccharide vaccines like PPSV23 1
• PCV20 has demonstrated robust immune responses to all 20 serotypes when administered as a single dose 4, 6
• PCV21's approval was based on considerations of immunogenicity, safety, and resource use 1

Current ACIP Recommendations

• ACIP recommends that all adults aged ≥65 years and adults aged 19-64 years with risk conditions receive a pneumococcal conjugate vaccine 1
• Options currently include either PCV20 alone or PCV15 followed by PPSV23 1
• PCV21 has been recently added to these recommendations as another option for pneumococcal vaccination 1
• For adults who have not received any pneumococcal vaccine or whose vaccination history is unknown, a single dose of any available PCV (including PCV20 or PCV21) is recommended 1, 5

Safety Profile

• Both PCV20 and PCV21 have demonstrated acceptable safety profiles in clinical trials 4, 6
• Common adverse reactions for pneumococcal conjugate vaccines include injection site reactions and mild systemic symptoms such as fatigue and headache 7, 6
• The safety profile of PCV20 has been found to be similar to that of PCV13 4

Clinical Impact

• Pneumococcal disease causes significant morbidity and mortality, with case fatality ratios exceeding 10% in adults aged ≥65 years and those with certain underlying conditions 1
• Expanding serotype coverage with newer vaccines like PCV20 and PCV21 aims to reduce the burden of invasive pneumococcal disease caused by serotypes not covered by earlier vaccines 4
• The introduction of these newer vaccines represents an important advancement in preventing pneumococcal infections and their potentially severe complications 2

Common Pitfalls to Avoid

• Don't confuse PCV21 with PCV20 or assume they contain the same serotypes - they have different compositions 1
• Remember that patients who have already received a pneumococcal vaccine should wait at least 1 year after PPSV23 or at least 8 weeks after PCV13 before receiving a newer pneumococcal conjugate vaccine 5
• Avoid missing vaccination opportunities in high-risk individuals, as pneumococcal vaccination remains underutilized despite recommendations 2