IXIARO® updated: overview of clinical trials and developments with the inactivated vaccine against Japanese encephalitis

The mosquito-borne Japanese encephalitis virus causes an estimated 50,000cases in Asia, accounting for at least 10,000deaths and 15,000cases of neuropsychiatric sequelae. IXIARO((R)) (Intercell AG, Vienna, Austria), an inactivated, Vero cell-derived vaccine against Japanese encephalitis was introduced in 2009. The vaccine is highly immunogenic, showing significantly higher geometric mean antibody titers compared with previous, mouse brain-derived vaccines. Postmarketing studies have confirmed the excellent safety profile. Studies on children aged 2months to 18years have been published. Based on these data, positive opinion from the EMA for vaccination of children has recently been given. Since a safe and effective vaccine against Japanese encephalitis is now available, outdated guidelines and recommendations have to be revised: travelers to rural areas of Asia should generally be recommended vaccination.