Adult vaccination with 13-valent pneumococcal conjugate vaccine is currently recommended in the UK only for very high-risk individuals, with 23-valent pneumococcal polysaccharide vaccine (PPV23) being recommended to all adults 65 years or older and those 18 years or older with specified risk conditions. A 20-valent pneumococcal conjugate vaccine (PCV20) has recently become available for use in adults with potential to address a substantial proportion of the current adult pneumococcal disease burden in the UK. We evaluated the cost-effectiveness of PCV20 vaccination compared with PPV23 in adults in England currently eligible for pneumococcal vaccination.

A probabilistic model with a Markov-type process was used to depict lifetime risks and costs of pneumococcal disease among a cohort of English adults. Epidemiologic parameters, serotype coverage, costs, vaccine effectiveness and coverage were based on published literature or publicly available data. The National Health Service perspective was adopted, health effects were expressed in quality-adjusted life years (QALYs), and future costs and QALYs were discounted at 3.5 percent.

Results suggest that under reasonable assumptions concerning disease burden, vaccine, effectiveness, and vaccine cost, PCV20 implementation of an age-and risk-based strategy targeting all adults aged 65 years or older and younger risk group adults aged 18 to 64 years would reduce a large number of pneumococcal disease hospitalizations and pneumococcal-related deaths compared to currently recommended PPV23.

The incremental cost-effectiveness ratio was well below the current willingness-to-pay range of GBP20,000-GBP30,000 per QALY gained, with PCV20 being cost saving compared with PPV23 in base case and most sensitivity analyses. Probabilistic sensitivity analysis suggests high certainty in recommending PCV20 for vaccination of adults aged 18 to 64 years in risk groups and all aged 65 years or older instead of PPV23.

Our findings support replacing PPV23 with PCV20 to directly protect adults against pneumococcal disease, reducing hospitalizations and saving lives in the UK.