Objectives: The Singapore Ministry of Health previously recommended vaccination with 23-valent pneumococcal polysaccharide vaccine (PPSV23) in adults aged 18 to 64 years with chronic medical conditions (“at risk”), 13-valent pneumococcal conjugate vaccine (PCV13) followed by PPSV23 (PCV13 / PPSV23) with PPSV23 revaccination in adults aged 18 to 64 years with immunocompromising conditions (“high risk”), and PCV13 / PPSV23 in all adults aged ≥65 years. Recently a single dose of 20-valent PCV (PCV20) was recommended as an alternative. We conducted a cost-effectiveness analysis of PCV20 versus the previous recommendations.
Methods: Risks and costs of invasive pneumococcal disease, all-cause nonbacteremic pneumonia, and the expected impact of vaccination were projected over a lifetime modeling horizon using a probabilistic cohort model. Model inputs were based on local data, as available. Cost per quality-adjusted life year (QALY) gained with PCV20 (vs current recommendations) was assessed overall and among subgroups of the target population from a healthcare system perspective (discounting, 3%/ year). Sensitivity analyses were also conducted.
Results: PCV20 was estimated to reduce invasive pneumococcal disease cases by 41, nonbacteremic pneumonia cases by 4335, and deaths by 196 among the model population (N = 1.6M). Net costs (vaccination + medical) and QALYs increased by S$0.3 million and 2693, respectively, yielding a cost/QALY of S$105 for PCV20. PCV20 was dominant among high-risk adults aged 18 to 64 years and all adults 65 to 99 years; among at-risk adults aged 18 to 64 years, cost/QALY for PCV20 was S$2081. PCV20 remained cost-saving or highly cost-effective in sensitivity analyses.
Conclusions: Cost-effectiveness analysis suggests use of PCV20—in lieu of previous Singapore Ministry of Health recommendations for adult pneumococcal vaccination—would represent a cost-effective use of scarce healthcare resources.