Systematic Review and Meta-Analysis of the Efficacy and Effectiveness of Pneumococcal Vaccines in Adults

The 13-valent pneumococcal conjugate vaccine (PCV13) and 23-valent pneumococcal polysaccharide vaccine (PPSV23) were previously recommended for adults in the United States. To help inform discussions on recently licensed 15- and 20-valent pneumococcal vaccine use among adults, we conducted a systematic review of PCV13 and PPSV23 efficacy or effectiveness. We conducted a search on PCV13 and PPSV23 efficacy or effectiveness (VE) studies against vaccine type (VT) invasive pneumococcal disease (IPD) and VT-pneumococcal pneumonia in adults. Nineteen studies were included: 13 on VT-IPD (four on PCV13, nine on PPSV23) and eight on VT-pneumococcal pneumonia (three on PCV13, four on PPSV23, one on PCV13 and PPSV23). One randomized-controlled trial (RCT) evaluated PCV13 and observed an efficacy of 75% and 45% against VT-IPD and VT-pneumococcal pneumonia, respectively. No RCTs reported PPSV23 efficacy. PCV13 effectiveness estimates against VT-IPD ranged from 47% to 68%. Pooled PPSV23 effectiveness against VT-IPD was 45% (95% CI: 37%, 51%; I2=0%). PCV13 VE estimates against VT-pneumonia ranged from -2 to 46%. Pooled PPSV23 VE against VT-pneumococcal pneumonia was 18% (95% CI: -4%, 35%; I2=0%). Evidence suggests PCV13 and PPSV23 are effective against VT-IPD and VT-pneumococcal pneumonia in adults; this was used to inform PCV15 and PCV20 policy decisions.