Immunogenicity and safety of IXIARO (IC51) in a Phase II study in healthy Indian children between 1 and 3 years of age.

For adults the standard administration of the Japanese encephalitis vaccine IXIARO is two injections of 6 microg in a 28-day interval. Immunogenicity and safety of 3 and 6 microg of IXIARO compared to JenceVac were investigated in 60 healthy Indian children aged between 1 and 3 years. JE specific neutralizing antibodies were measured at baseline and 28 days after the first and second vaccination. On Day 56 SCR of the 3 and 6 microg IXIARO and the JenceVac group were 95.7%, 95.2% and 90.9%, respectively, and GMT were 201, 218 and 230, respectively, both without statistically significant difference between the three groups. Local and systemic tolerability were captured in a diary 7 days post-vaccination. No apparent difference was seen in the safety profile between the vaccines. These first immunogenicity and safety data in children are promising and support the use of a 3 microg dose in children below the age of three for further development of IXIARO in the paediatric population.