The risk of Streptococcus pneumoniae infection varies widely with age, underlying disease, and living environment. Worldwide, infants and the elderly are at high risk for pneumococcal disease. Disease from pneumococcal infections can affect multiple organ systems and lead to multiple disease syndromes. This vaccine has a higher coverage rate, capable of reaching more than 94%. With the high coverage rate, it can effectively prevent the occurrence of serotype substitution and the outbreak of antibiotic-resistant pneumococcal-associated diseases.~This clinical trial is a Phase Ib clinical trial in adults aged 50 years and older based on the Phase Ia clinical trial.
Streptococcus pneumoniae infections often cause serious health problems, especially in infants and the elderly. Failure to cover all polysaccharide types of vaccines is a greater problem for adults than for children.~The purpose of this study was to preliminarily evaluate the safety and immunogenicity of a recombinant pneumococcal protein vaccine applied to adults aged 50 years and older to provide a basis for subsequent clinical trial design.