Monitoring JE Antibody Levels in Healthy Populations and Immunization Strategy in Low-Prevalence Areas

NCT06678373 | Active Not Recruiting Phase 4

• 1 other identifier: CDB-JE-PM-2023004
• Study Type: interventional
• Target: 250
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to assess the neutralizing antibody levels and prevalence risk of Japanese encephalitis among residents in low-endemic areas, as well as to evaluate the immunogenicity, safety, and immune persistence of the inactivated Japanese encephalitis vaccine across different age groups in healthy populations. The study uses an open-label, single-arm trial design with a sample size of 250 participants. Primary endpoints include pre- and post-vaccination serum neutralizing antibody levels, seroconversion rates, and incidence of adverse events.

Conditions

Japanese Encephalitis

Outcome Measures

Primary Outcomes (2)

• Assessment of JE neutralizing antibody levels in low-prevalence areas to evaluate the risk of JE transmission.

  Before administering the first dose of the vaccine, at least 3 ml of the recipient's venous blood will be collected. Transport the serum under frozen conditions to the testing laboratory for analysis. The serum Japanese encephalitis neutralizing antibodies will be detected using the Plaque Reduction Neutralization Test (PRNT50). A neutralizing antibody titer of \< 1:10 before vaccination is considered negative, while a titer of ≥ 1:10 after vaccination is considered positive. If the pre-vaccination antibody titer is ≥ 1:10, an increase of fourfold or more in the post-vaccination antibody titer is also considered a positive result.

  Prior to administration of the first vaccine dose.

• Seroconversion rate and average neutralizing antibody levels against JE on the 28th day after vaccination.

  After completing all doses of the trial, collect at least 3 ml of venous blood from the subjects on day 28. Transport the serum under frozen conditions to the testing laboratory for analysis. The serum Japanese encephalitis neutralizing antibodies will be detected using the Plaque Reduction Neutralization Test (PRNT50). A neutralizing antibody titer of \< 1:10 before vaccination is considered negative, while a titer of ≥ 1:10 after vaccination is considered positive. If the pre-vaccination antibody titer is ≥ 1:10, an increase of fourfold or more in the post-vaccination antibody titer is also considered a positive result.

  On the 28th day after vaccination.

Secondary Outcomes (2)

• Seroconversion rate and average neutralizing antibody levels against JE on the 365th day after vaccination.

  On the 365th day after vaccination.

• Adverse event rate

  Within 30 days after vaccination.

Study Arms (5)

Group A(Ages 6 to 17)

EXPERIMENTAL

The patient needs to receive 1 dose of inactivated Japanese encephalitis vaccine.

Biological: Liaoning Chengda Inactivated Japanese Encephalitis Vaccine

Group B(Ages 18 to 39)

EXPERIMENTAL

The patient needs to receive 2 doses of inactivated Japanese encephalitis vaccine, with an interval of 28 days.

Biological: Liaoning Chengda Inactivated Japanese Encephalitis Vaccine

Group C(C1 Age 18-39 years)

EXPERIMENTAL

The patient needs to receive 2 doses of inactivated Japanese encephalitis vaccine, with an interval of 7 days.

Biological: Liaoning Chengda Inactivated Japanese Encephalitis Vaccine

Group C(C2 Age 40-59 years)

EXPERIMENTAL

The patient needs to receive 2 doses of inactivated Japanese encephalitis vaccine, with an interval of 7 days.

Biological: Liaoning Chengda Inactivated Japanese Encephalitis Vaccine

Group C(C3 Age 60 years and above)

EXPERIMENTAL

The patient needs to receive 2 doses of inactivated Japanese encephalitis vaccine, with an interval of 7 days.

Biological: Liaoning Chengda Inactivated Japanese Encephalitis Vaccine

Interventions

Liaoning Chengda Inactivated Japanese Encephalitis Vaccine BIOLOGICAL

The patient needs to receive 1 dose of inactivated Japanese encephalitis vaccine.

Group A(Ages 6 to 17)

Eligibility Criteria

• Age: 6 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• Permanent residents aged 6 years (inclusive) and older;
• Healthy individuals as determined clinically after inquiring about medical history and conducting relevant physical examinations;
• Individuals who meet the vaccination criteria for the inactivated Japanese encephalitis vaccine (Vero cells);
• Participants must provide informed consent to receive vaccination and blood c collection; minors must obtain informed consent from their guardians;
• Participants planned to be included in Group A must have previously completed the full vaccination schedule for the Japanese encephalitis vaccine (including live attenuated vaccine or inactivated vaccine).

You may not qualify if:

• Participants are unwilling to sign the informed consent form;
• History of allergy to the vaccine or its components, severe adverse reactions to the vaccine such as allergies, urticaria, breathing difficulties, angioedema, or abdominal pain;
• Individuals with encephalopathy, uncontrolled epilepsy, and other progressive neurological diseases;
• History of seizures or convulsions, or family history of psychiatric disorders;
• Presence of congenital malformations or developmental disorders, genetic defects, and severe malnutrition;
• Individuals with autoimmune diseases, congenital or acquired immunodeficiencies, or family history of autoimmune diseases or immunodeficiencies;
• Any acute diseases or acute exacerbations of chronic diseases in the past 7 days;
• Treatment with immunosuppressants, anti-allergy treatments, cytotoxic therapies, or inhaled corticosteroids (excluding corticosteroid spray treatments for allergic rhinitis or topical corticosteroid treatments for acute non-complicated dermatitis) in the past 6 months;
• Administration of immunoglobulin injections within 1 month prior to vaccination;
• Individuals with fever before vaccination, with axillary temperature \>37.0°C;
• History of Japanese encephalitis;
• Other factors deemed inappropriate for participation in the clinical observational study as determined by the researcher;
• Pregnant women.

Sponsors & Collaborators

• Liaoning Chengda Biotechnology CO., LTD: lead

Study Sites (1)

Liaoning Provincial Center for Disease Control and Prevention

Shenyang, Liaoning, 110100, China

Location

MeSH Terms

Conditions

Encephalitis, Japanese

Condition Hierarchy (Ancestors)

Encephalitis, Arbovirus; Encephalitis, Viral; Central Nervous System Viral Diseases; Central Nervous System Infections; Infections; Infectious Encephalitis; Arbovirus Infections; Vector Borne Diseases; Mosquito-Borne Diseases; Virus Diseases; RNA Virus Infections; Flavivirus Infections; Flaviviridae Infections; Encephalitis; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neuroinflammatory Diseases

Study Officials

• Xing Fang

  Liaoning Provincial Center for Disease Control and Prevention

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: November 6, 2024
• First Posted: November 7, 2024
• Study Start: November 14, 2024
• Primary Completion: April 30, 2026
• Study Completion (Estimated): December 31, 2026
• Last Updated: December 13, 2024

Record last verified: 2024-12

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)