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 is a Phase 3 randomized, observation-blinded, active-controlled, parallel-group clinical trial designed to evaluate the immunogenicity, safety, and functional antibody response of the experimental vaccine versus the control vaccine in healthy Thailand infants vaccinated at a 2+1 schedule (2 months, 4 months and 12-15 months). The trial will enroll approximately 600 healthy infants aged 2 months (at least 6 weeks) who will be randomly assigned in a 1:1 ratio to receive either the experimental or control vaccine, with 100 in each group (200 in total) randomized to subgroups and subject to additional immunogenicity assessments. All participants will be evaluated for solicited adverse events for 7 days and unsolicited adverse events for 30 days post each vaccination. Immunogenicity evaluation will be performed in all participants at baseline and post the booster dose, while the sub-cohort participants will be evaluated for post primary series immunogenicity additionally.

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.

This is a phase I/II randomized, double-blind, and positive-controlled study. Participants in the phase I toddler group will receive 1 dose of either high dose VLP-Polio (Dose H) or control vaccine in a ratio of 3:1. The phase I infant cohort will have 4 arms randomly assigned to receive either investigational vaccine (Low-adjuvant dose VLP-Polio, Medium dose VLP-Polio, or High dose VLP-Polio or control vaccine in a ratio of 3:1. Phase II infant cohort will have 4 arms randomly assigned to receive either investigational vaccine (Low-adjuvant dose VLP-Polio, Medium dose VLP-Polio, or High dose VLP-Polio or control vaccine in a ratio of 3:1. Each infant participant will be administrated 3 doses of the assigned vaccine with 28 days apart, and the booster dose will be given when the infant is 12-18 months old. Enrollment of Phase I and Phase II will be staggered in descending order of age group but ascending order of dosing levels. Blood and mucosal samples will be collected for immunogenicity evaluation over the time course of the study.