Antibody Persistence against Diphtheria, Tetanus, Pertussis, Hepatitis B, Measles, Mumps and Rubella in Thai Children Following Immunization with Pentavalent and Hexavalent Vaccines

Antibody Persistence against Diphtheria, Tetanus, Pertussis, Hepatitis B, Measles, Mumps and Rubella in 9 to 12 Year Old Thai Children Following Immunization with Pentavalent and Hexavalent Vaccines, and the Immunogenicity of Tdap Administered at 11 Years of Age

Status

Active, not recruiting

Phases

Unknown

Study type

Observational

Source

TCTR

Registry ID

TCTR20260626009

Enrollment

200

Registered

2026-06-26

Start date

2026-07-01

Completion date

Unknown

Last updated

2026-08-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

healthy children receiving pentavalent and hexavalent vaccines diphtheria, tetanus, pertussis, hepatitis B, measles, mumps, and rubella, immunogenicity

Interventions

All enrolled participants will receive a single intramuscular dose 0.5 mL of recombinant acellular Tdap vaccine Boostagen BioNetAsia Co Ltd Thailand as a pre-adolescent booster. Each 0.5 mL dose conta

Prevention

Vaccine group

Eligibility

Sex/Gender

All

Age

8 Years to 12 Years

Inclusion criteria

Inclusion criteria: 1. Previously enrolled in the predecessor studies and completed follow-up to age 8 years. 2. Received the full primary immunization series (DTwP-HB-Hib or DTaP-HB-Hib-IPV at 2, 4, 6 months) and first booster (at 18 months) per the original protocol, as well as the second booster (Tdap-IPV, Boostrix-IPV) at 4 years of age. 3. Good general health at time of enrolment into the present extension study. 4. Legally authorized representative (LAR; parent or guardian) is willing and able to bring the participant for all scheduled visits at ages 9, 10, 11, 11 years + 1 month, and 12 years at King Chulalongkorn Memorial Hospital.

Exclusion criteria

Exclusion criteria: 1. Serious underlying medical condition, including but not limited to: genetic disorders (e.g., Down syndrome), immunosuppressive state or receipt of immunosuppressive agents, HIV infection, chronic pulmonary or cardiac disease, chronic hepatic or renal disease, or history of chronic or recurrent infections. 2. Known primary immunodeficiency, including: severe X-linked agammaglobulinaemia, common variable immunodeficiency (CVID), specific antibody deficiency (SAD); severe combined immunodeficiency (SCID), combined immunodeficiency, hyper-IgM syndrome, DiGeorge syndrome; chronic granulomatous disease (CGD), Schwachman-Diamond syndrome; or disorders of the complement cascade. 3. LAR declines to provide consent. 4. Child declines to provide assent at age 9 years.

Design outcomes

Primary

Measure	Time frame
Antibody persistence 9, 10, 11 and 12 years Seropositive or seroprotection rate	—

Secondary

Measure	Time frame
Antibody levels 9, 10, 11 and 12 years geometric mean concentration (GMC)	—

Countries

Thailand

Contacts

Public ContactNasamon Wanlapakorn

Chulalongkorn University

nasamon.w@chula.ac.th022564000

Outcome results

None listed

Source: TCTR (via WHO ICTRP) · Data processed: Aug 10, 2026