Immunogenicity and Safety of ChimeriVax™ Japanese Encephalitis Vaccine in Thai Toddlers and Children...
Japanese EncephalitisHepatitis ASafety: To describe the safety profiles following vaccination. Immunogenicity: To describe the immune response after a single dose of vaccine.
Comparison of Three Commercial Batches of the Japanese Encephalitis Vaccine IC51
Japanese EncephalitisThe objective is to demonstrate equivalence of three commercial IC51 batches in terms of geometric mean titers for anti-JEV neutralizing antibody
Safety and Efficacy Study of ChimeriVax™-JE and JE Inactivated Mouse Brain Vaccine in Children of...
Japanese EncephalitisThis 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.
Boosterability of Live Attenuated Japanese Encephalitis (JE) Vaccine in Children Who Have Previously...
Japanese EncephalitisTo facilitate introduction of live attenuated SA 14-14-2 Japanese encephalitis vaccine (LJEV) into the National Immunization Programme of Sri Lanka, we evaluated the safety and immunogenicity of co-administration of LJEV and measles vaccine in children at 2 and 5 years of age. The primary hypothesis was that the seropositivity rate at 28 days post vaccination of SA 14-14-2 in subjects 2 and 5 years of age who have already received at least two doses of mouse brain-derived inactivated JE vaccine is greater than 80%. Japanese encephalitis virus is the leading cause of viral neurological disease and disability in Asia. The severity of sequelae, together with the volume of cases, make JE the most important cause of viral encephalitis in the world. Approximately 3 billion people-including 700 million children-live in areas at risk in Asia for JE. JE most commonly infects children between the ages of 1 and 15 years, and can also infect adults in areas where the virus is newly introduced. More than 50,000 cases are reported annually and cause an estimated 10,000 to 15,000 deaths. This figure is believed to represent only a small proportion of the disease burden that actually exists.
A Safety and Efficacy Study of Two Japanese Encephalitis Vaccines ChimeriVaxTM-JE and JE-VAX
Japanese EncephalitisThe purpose of this study is to determine non-inferiority in seroconversion and to compare the safety and tolerability between ChimeriVax™-JE and JE-VAX® to the respective homologous virus strain and several wild types strains after completion of vaccination course.
Determining Safety and Efficacy of Japanese Encephalitis Vaccine When Given With Measles Vaccine...
EncephalitisJapanese BThis study will determine whether it is safe and effective to administer Japanese encephalitis (JE) live attenuated SA 14-14-2 vaccine at the same time as measles vaccine. If it is found to be safe, it will pave the way for use in routine vaccination programs. The hypothesis is that children who receive JE live attenuated SA 14-14-2 vaccine and measles vaccine at the same time are protected against these diseases at the same level as those who receive the vaccines at different intervals.
A Prospective, Open Label Study of Human T Cell Responses to Live Attenuated Japanese Encephalitis...
Japanese EncephalitisJapanese Encephalitis VaccineJapanese encephalitis (JE) live attenuated vaccine SA14-14-2 has been in use for more more than 20 years in Asia. JE vaccine SA14-14-2 is licensed in India and has been widely used since 2006. JE vaccines give protection by generating a neutralizing antibody response, but both naturally exposed persons and patients with JE also have T cell responses. Whether JE vaccine SA14-14-2 elicits T cell responses is unknown. This study tests the hypothesis that T cell responses are generated in response to JE SA14-14-2 vaccination. The aim of this study is to characterize T cell responses to JE vaccine SA14-14-2 in healthy people, and to investigate differences in T cell responses between natural exposure, vaccination and disease.
The Role of Pre-existing Cross-reactive Antibodies in Determining the Efficacy of Vaccination in...
Yellow FeverEncephalitis1 moreEpidemic viral diseases have become more prevalent in recent years. Among the various strategies to prevent such epidemics, vaccination is the most cost-effective. However, populations that are immunized are typically already exposed to multiple previous vaccinations or natural infections. Studies from this and other laboratories have revealed that pre-existing dengue antibodies can either inhibit or enhance subsequent dengue infection depending on the pre-existing antibody levels. While cross-reactive antibody is potentially pathogenic in dengue, how it impacts immune response to vaccination is unclear. Indeed, aggregated at the site of vaccination and the respective draining lymph nodes are antigen-presenting and immune regulatory cells that express Fc receptors and play pivotal roles in determining the magnitude and polarity of the immune response. Vaccine uptake by these antigen-presenting cells may thus be either inhibited or enhanced when vaccines are opsonized with cross-reactive antibodies. In view of the limited knowledge on how cross-reactive antibodies affect vaccination outcome, investigators propose here a study that exploits the known cross reactivity between Japanese encephalitis (JE) virus antibody and yellow fever (YF) vaccine. Investigators hypothesize that cross-reactive antibodies impacts antibody response to YF at the point vaccination in a concentration-dependent manner by altering both vaccine uptake and the innate immune response by antigen presenting cells. Investigators will structure an open label clinical trial on sequential vaccination with JE and YF vaccines, with different time intervals between vaccinations. This would test immune response to YF vaccination in subjects with different titer of cross-reactive JE vaccine-derived antibodies.
Long Term Immunity and Safety Following Vaccination With the JEV IC51 (IXIARO®, JESPECT®) in Pediatric...
Japanese EncephalitisThe study investigates long-term immunity and safety of IC51 (IXIARO®, JESPECT®) in a pediatric population vaccinated in the parent study IC51-322.
Treatment of Japanese Encephalitis
Japanese EncephalitisJapanese encephalitis is the single largest cause of viral encephalitis in the world today. It occurs in yearly post monsoon outbreaks in Uttar Pradesh and other parts of India and south east Asia. There is presently no antiviral drug of proven benefit for this illness and treatment is mostly supportive. The drug Ribavirin is already in the market in use for other indications. It has been found useful in West Nile encephalitis and various hemorrhagic fevers caused by related arboviruses. This is a double blind placebo of Ribavirin in Japanese encephalitis. To the best of our knowledge, this is the first such trial in the world. The study hypothesis is that children treated with ribavirin will be no different from those getting placebo in terms of mortality, length of hospital stay, days to return to consciousness and oral feeds, days to become afebrile and convulsion free and in 3 month sequelae rate.