NCT06825312

Immunogenicity, Safety, and Antibody Persistence of Different Immunization Strategies Against Japanese Encephalitis

• Status: Active Not Recruiting
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 600 (estimated)
• Sponsor: Liaoning Chengda Biotechnology CO., LTD · Industry
• Sex: All
• Age: 8 Months – 8 Months
• Healthy volunteers: Accepted

Summary

The main objective of this study is to evaluate the persistence of Japanese encephalitis antibodies in participants at the age of 6, after they have followed different Japanese encephalitis vaccination schedules. Furthermore, the study will assess the immunogenicity and antibody persistence of primary immunization across different Japanese encephalitis vaccination schedules, as well as the immunogenicity following booster immunizations within these schedules. The safety of each vaccine dose will also be evaluated.

Detailed description

This is a randomized, controlled, open-label, non-inferiority study. Healthy children aged 8 months will be invited to participate and randomly allocated to six groups (Group 1 to Group 6) in a 1:1:1:1:1:1 ratio. They will be administered the inactivated Japanese encephalitis vaccine (JEV-I) and/or the live attenuated Japanese encephalitis vaccine (JEV-L) based on the six schedules delineated in the protocol. The primary immunization will be administered to participants at 8 months of age, and a booster dose will be given at 24 months of age. Additionally, participants in Groups 1, 2, and 5 will receive an additional booster dose at the age of 6. Blood samples (3 mL) will be collected from participants at 8 months, 24 months, and 6 years of age. Samples will be taken before vaccination and 30 days after it for detecting Japanese encephalitis neutralizing antibodies. The titers of these antibodies will be assayed via the 50% plaque reduction neutralization test. Those in groups 3, 4, and 6 who've completed all immunization procedures by 24 months old will have a blood sample taken at 6 years old.

Conditions

• Japanese Encephalitis Vaccine

Interventions

Type	Name	Description
BIOLOGICAL	Japanese Encephalitis Vaccine (Vero Cell), Inactivated	0.5ml for each dose, manufactured by Liaoning Chengda Biotechnology Co., Ltd., administered in the deltoid area of lateral arm by intramuscular injection.
BIOLOGICAL	Japanese Encephalitis Vaccine, Live	0.5ml for each dose, manufactured by Chengdu Institute of Biological Products Co., Ltd., administered subcutaneously in the lower part of the deltoid area of lateral arm.

Timeline

• Start date: 2023-11-11
• Primary completion: 2030-12-31
• Completion: 2031-12-31
• First posted: 2025-02-13
• Last updated: 2025-03-11

Locations

6 sites across 1 country: China