Clinical Trial: Immunogenicity and Safety of Inactivated Vero Cell Derived Japanese Encephalitis Vaccine in Thai Children

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Immunogenicity and Safety of Inactivated Vero Cell Derived Japanese Encephalitis Vaccine in Thai Children

Brief Summary:

Japanese encephalitis (JE) is the main cause of viral encephalitis in many countries of Asia including Thailand. Estimated annual mortality ranges from10,000-15,000 deaths, while the total number of clinical cases is about 50,000. Of these cases, about 50% result in permanent neuropsychiatric sequelae. The disease occurs mostly among children aged <10 years. There is no specific antiviral treatment for JE. Vaccination is the single most important control measure. This study aims to evaluate the immunogenicity and safety of inactivated Vero cell derived JE vaccine (Beijing P-3 strain) produced by Liaoning Cheng Da Biotechnology Co., Ltd, China "JEVAC" in Thai children.

152 healthy Thai children aged between 1-3 years will be vaccinated with "JEVAC" in a dose of 0.5 mL. subcutaneously on Day 0, 1-4 weeks later and a booster vaccination at one year (totally 3 doses). Two mL. of blood will be drawn on Day 0, 4 weeks after second dose, at one year on booster vaccination day and 4 weeks after the booster (totally 8 mL. of 13 months study period) for determination of JE neutralizing antibodies (PRNT50) using Beijing P3 strain. Adverse events will be observed for 28 days after each vaccination. Serious adverse events will be observed throughout the study period.


Detailed Summary:
Sponsor: Mahidol University

Current Primary Outcome: Seroconversion Rate After Primary Vaccination [ Time Frame: 28 days after second dose of JEVAC ]

To determine the seroconversion rate by using neutralizing antibody (NT) against JE virus (Beijing P3 strain) JE virus from <10 on before first vaccination To >= 10 at 28 days after second vaccination (primary vaccination). Those who have NT titer >=10 before first vaccination, will not be included in immunogenicity evaluation.


Original Primary Outcome: Seroconversion Rate After Primary Vaccination [ Time Frame: March 2011 ]

To determine the seroconversion rate of JEVac Tm after primary vaccination


Current Secondary Outcome:

  • Geometric Mean Titer of NT After Primary and Booster Vaccination [ Time Frame: 28 days after second vaccination, before and 28 days after booster vaccination with JEVAC ]
    To determine the geometric mean titers (GMT) of neutralizing antibody of JEVAC 1 month after primary and then before and after booster vaccinations.
  • Adverse Events of Vaccine [ Time Frame: 7, 14, 28 days after each vaccination and throughout the study period for local, solicited systemic, unsolicited systemic and serious adverse events, respectively ]
    To determine the adverse events of JEVAC
  • Neutralizing Antibody Persistence One Year After the Primary Vaccination [ Time Frame: 1 year after primary vaccination ]
    To determine the neutralizing antibody persistence one year after the primary JEVAC vaccination.


Original Secondary Outcome:

  • Geometric mean titer of NT after primary and booster [ Time Frame: March 2012 ]
    To determine the geometric mean titers (GMT) of neutralizing antibody of JEVACTM 1 month after primary and then after booster vaccinations.
  • Adverse Events of Vaccine [ Time Frame: september 2011 ]
    To determine the adverse events of JEvac TM along the study
  • neutralization antibody persistence one year after the primary vaccination [ Time Frame: march 2012 ]
    To determine the neutralization antibody persistence one year after the primary JEVACTM vaccination.


Information By: Mahidol University

Dates:
Date Received: August 2, 2011
Date Started: May 2010
Date Completion:
Last Updated: November 14, 2014
Last Verified: November 2014