Ixiaro, the only vaccine licensed for Japanese encephalitis, is a purified formalin-inactivated whole-virus, cultivated in Vero-cells. Ixiaro should be considered for use in individuals at risk of exposure to Japanese encephalitis through travel or in the course of their occupation.
A study looked at the seroconversion in three dosing schedules: 6 microgram injection on days 0 and 28; 6 microgram injection on day 0; and 12 microgram on day 0. Those who did not receive two doses of the vaccine received placebo on day 28. 97.3% of patients on the two-dose schedule reached seroconversion on day 56 compared to 25.6% in the single 6 microgram group and 41.2% in the single 12 microgram group.1
Another study compared the use of Ixiaro with a previously licensed vaccine to test its immunogenicity; 98% seroconversion was seen in patients who received Ixiario compared to 95% seen in the previously licensed vaccine group.2 There were no serious adverse effects seem in either group with the most common adverse effects including headache, flu-like illness, myalgia and fatigue.2
- Schuller E et al. Vaccine 2008; 10.1016
- Tauber E et al. Lancet 2007; 370: 1847-53
Further information: Novartis