Clinical trials

This clinical study will enroll 100 participants from the 2-month-old (minimum 6 weeks) group who previously participated in the Phase III clinical trial of the 13-valent pneumococcal polysaccharide conjugate vaccine (CRM197, TT vector) (Protocol No.: CS-CTP-PCV), with 50 participants in each of the treatment and control groups, and who have completed blood sample collection for the 1-year and 2-year immunogenicity studies. All participants will have 3.0-3.5 mL of venous blood collected for the immunogenicity study.

This clinical trial consists of Phase I and Phase II. The objective is to evaluate the safety and immunogenicity of the 24-valent pneumococcal polysaccharide conjugate vaccine (CRM197/tetanus toxoid) in individuals aged 2 months (minimum 6 weeks) and older.

This clinical trial will enroll 160 participants who previously took part in the Phase I clinical trial of the adsorbed acellular pentavalent (five-component) DTP-polio combination vaccine (for individuals aged 6 years and older) (Protocol No.: CTP-Tdcp-001). Approximately 3-4 mL of venous blood will be collected from each participant 2.5 years, 5 years, and 10 years after vaccination for a study on immune persistence.

This study included 180 trial participants who had previously taken part in the Phase IIIb clinical trial of the ACYW135 group meningococcal polysaccharide-conjugated vaccine (CRM197 carrier) for children aged 4-6 years (Protocol No.: CTP-MCVF-002) and had completed blood sample collection at 90 and 180 days post-vaccination; there were 90 participants in each of the treatment and control groups. All trial participants were required to provide 3.0-4.0 mL of blood samples for immunopersistence assessment at 3 and 5 years post-vaccination, respectively.

This clinical trial is conducted in two parts. Part One employs a randomized, partially blinded, dose-escalation, partially active-controlled design. Part Two utilizes a randomized, blinded, placebo-controlled design. Part One is divided into four stages based on age and vaccine dose levels. Part Two consists of the 2-month-old vaccine/placebo groups.