A randomized trial of simultaneous versus sequential pneumococcal vaccination in elderly

Area of Science:

• Immunology
• Vaccinology
• Geriatric Medicine

Background:

• Pneumococcal vaccines, including the 13-valent pneumococcal conjugate vaccine (PCV13) and the 23-valent polysaccharide vaccine (PPSV23), are crucial for preventing pneumococcal disease in the elderly.
• Understanding the optimal vaccination schedule to maximize immune responses in older adults is essential for public health.

Purpose of the Study:

• To compare the antigen-specific memory B cell responses elicited by simultaneous PCV13 and PPSV23 vaccination versus sequential (PCV13 followed by PPSV23) or single PPSV23 vaccination in elderly individuals.
• To assess the safety and immunogenicity of different pneumococcal vaccination strategies over a 24-month period.

Main Methods:

• A monocentric, randomized trial involving vaccine-naïve adults aged 60 years or older.
• Participants were assigned to receive simultaneous, sequential, or single PPSV23 vaccination.
• The primary outcome measured was the change in memory B cells specific for four key vaccine serotypes at 27-28 weeks post-vaccination compared to baseline.

Main Results:

• No significant difference in memory B cell responses was observed across all four vaccine serotypes between simultaneous, sequential, and single vaccination groups at the primary endpoint.
• At six months, the simultaneous vaccination group showed a lower memory B cell response for serotype 19A compared to the sequential group.
• Sequential vaccination resulted in higher 24-month IgG responses against serotype 3 compared to simultaneous or single vaccination.

Conclusions:

• Simultaneous vaccination with PCV13 and PPSV23 does not provide superior memory B cell responses compared to sequential or single PPSV23 vaccination in the elderly.
• All evaluated vaccination schedules demonstrated a favorable safety profile with no serious adverse events reported.