Safety and Efficacy Study of ChimeriVax™-JE and JE Inactivated Mouse Brain Vaccine in Children of Descending Age

Randomised, Double Blind, Controlled, Safety, Tolerability and Immunogenicity Phase II Trial of ChimeriVax™-JE and Japanese Encephalitis Inactivated Mouse Brain Vaccine in Children of Descending Age.

This randomised, double-blind study is to be conducted on 96 subjects at multiple sites in India. Subjects will be enrolled by age group and randomised to either ChimeriVax™-JE (JE-CV) or JE Mouse Brain Derived Vaccine (JE-MBDV). Study consists of a screening period, a treatment period and a 2 year follow-up period.

Primary safety endpoints will be the adverse event (AE) rates 28 days after completion of vaccination course. The primary efficacy endpoints will be the rate of seroconversion 28 days after completing vaccination.

Inclusion Criteria:

• All aspects of the Protocol explained and written informed consent obtained from the subject's parent or guardian and assent from the child if ≥ 8 years of age.
• Aged ≥ 9 months to < 10 years
• In good general health, without significant medical history, physical examination findings, or clinically significant abnormal laboratory results
• Subject had to be available for the study duration for the study duration, including all planned follow-up visits.

Exclusion Criteria:

• A history of vaccination against, or infection with, JE or other flaviviruses (e.g. Kyanasur Forest Disease, West Nile virus, dengue fever). Previous JE vaccination was to be determined by history (interview of subject's parent or guardian) or by inspecting the child's official vaccination record.
• Demonstration of parasitemia on malaria blood smear at Screening.
• History of residence in or travel to a JE-endemic region of India or elsewhere in Asia (for periods of 4 weeks or more).
• hypersensitivity to thimerosal or gelatin
• Have received a transfusion of blood, blood products or serum globulin in the preceding 6 months,
• Have an immunodeficiency or neurological disorder, or take drugs that suppress the immune system,
• Have a history of severe reaction to other vaccines,
• Have a chronic condition requiring medication,
• Intend to travel out of the area during the study period,
• Have spent at least 4 weeks in a JE-endemic region,
• Plan to receive any other vaccination within the double-blind treatment period, or who have received a vaccination in the month preceding Screening,
• Exhibit signs of secondary or tertiary malnutrition,
• Are seropositive to human immunodeficiency virus (HIV), Hepatitis B or C,
• Have malaria infection, or who have a fever within 3 days before vaccination.
• Those with an acute fever, or with previously scheduled vaccinations, may be rescheduled.
• Consideration of the routine immunisation schedule should be made such that it is ensured that routine vaccinations due are either given before entry to the trial, or afterwards if delayed because of the trial.