Diphtheria

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.

Pertussis remains a major global public health problem. In Thailand, pertussis vaccination is recommended during pregnancy at 20-32 weeks' gestation, together with routine childhood diphtheria-tetanus-pertussis vaccination administered as a primary series at 2, 4, and 6 months and booster doses at 18 months and 4-6 years of age. TdaP2gen, a newly developed combined tetanus, diphtheria, and recombinant genetically detoxified acellular pertussis vaccine containing 2 µg pertussis antigen, has shown favorable safety and non-inferior immunogenicity compared with existing pertussis vaccines. However, data on its use in pregnant women, transplacental antibody transfer, and potential immune interference in infants remain limited. This study aims to evaluate the safety and immunogenicity of TdaP2gen in pregnant women, assess antibody transfer to newborns, and investigate immune responses to tetanus, diphtheria, and pertussis following primary and booster pertussis-containing vaccinations in infants and toddlers, including comparisons between whole-cell and acellular pertussis-containing vaccine schedules.

the safety and tolerability of different dosages of adsorbed acellular pertussis (two-component) diphtheria-tetanus combined vaccine

This is a randomized, double-blinded, parallel-controlled phase I/II clinical trial to evaluate the safety and preliminary immunogenicity of the Tetanus, Diphtheria and Acellular Component Pertussis Vaccine Adsorbed (reduced antigen content) in subjects aged 6 years and above.

The purpose of this study is to evaluate immunogenicity, safety and lot-to-lot consistency of LBVD in comparison to co-administration of Pentavalent vaccine and Poliomyelitis Vaccine (Inactivated) in separate injections at four weeks after completion of three-dose primary series at 6-10-14 weeks of age when administered to healthy infants

This is a phase II, randomized, double-blind, active-controlled, parallel-group, multicenter study to evaluate the immunogenicity and safety of DTaP-HepB-IPV-Hib hexavalent vaccine LR20062 in healthy infants as primary series at 2, 4, 6 months of age.

The main purpose of this study is to evaluate immune persistence at 30 and 36 Months of Age and Pertussis Breakthrough Infections between 19 and 36 Months of Age following two regiments of DTaP-IPV/Hib Pentavalent Vaccine in Healthy 2-Month-Old Infants and Children in China.

This study is a randomized, blinded, active-controlled phase I clinical trial to evaluate the safety and preliminary immunogenicity of the Diphtheria-Tetanus-acellular Pertussis Component Combined Vaccine (DTacP) in subjects (aged 2 months to 6 years). Primary safety endpoints are the occurrence of solicited adverse events within 30 minutes after each dose, the occurrence of solicited adverse events within 7 days after each dose, the occurrence of unsolicited adverse events within 30 days after each dose, and the occurrence of adverse events 30 days after immunization. The secondary safety endpoint is the occurrence of serious adverse events (SAEs) within 12 months after immunization. Secondary immunogenicity endpoints are the geometric mean concentration (GMC), geometric mean fold increase (GMFI), seropositive rates, seroconversion rates, or 4-fold increase rates of anti-DT, anti-TT, anti-PT, anti-FHA, and anti-PRN antibodies 30 days after immunization. The exploratory endpoints are the GMC, GMFI, seropositive rates, seroconversion rates, or 4-fold increase rates of anti-DT, anti-PT, and anti-FHA neutralizing antibodies 30 days after immunization in all groups, the GMC and seropositive rates of anti-DT, anti-TT, anti-PT, anti-FHA, and anti-PRN antibodies 12 months after primary immunization in the infant group, the seropositive rates and geometric mean tie (GMT) of anti- type I, type II, type III poliovirus neutralizing antibodies 30 days after immunization in all groups, the seropositive rates and geometric mean tie (GMT) of anti- type I, type II, type III poliovirus neutralizing antibodies 12 months after primary immunization in the infant group.