Imojev (SC Injection)

Encephalitis vaccine is indicated for prophylaxis of Japanese encephalitis caused by the Japanese encephalitis virus, in persons from 9 months of age and over.

Vaccines, Anti-sera & Immunoglobulin

The vaccine is a live attenuated virus. Following administration, the virus replicates locally and elicits neutralising antibodies and cell-mediated immune responses that are specific to the Japanese encephalitis virus. Available results indicate that protection is mainly mediated by neutralising antibodies.

In nonclinical studies, all animals that received a single dose of the vaccine developed specific neutralising antibodies against Japanese encephalitis virus and were protected against infection by a virulent Japanese encephalitis virus experimental challenge.

A single dose administration of Encephalitis Vaccine is as immunogenic as a three-dose regimen of an inactivated Japanese encephalitis comparator vaccine administered in adults 18 years of age and over. A seroprotective level of antibodies is generally reached 14 days after vaccination. In persons 9 months of age and over, a seroprotective level of antibodies is generally reached 28 days after vaccination.

Persons 9 months of age and over: one single dose of reconstituted Encephalitis Vaccine 0.5 mL injection should be administered for primary immunization.

In children and adolescents up to 18 years of age, if a long term protection is required, one 0.5 mL dose of Encephalitis Vaccine should be given as a booster dose after the first vaccination. The booster dose should be given preferably 1 year after the first vaccination and can be given up to 2 years after the first vaccination.

Immunity is maintained at a high level at least 3 years after the booster dose. One 0.5 mL dose of Encephalitis Vaccine can also be given as a booster vaccination in children who were previously given inactivated Japanese encephalitis vaccine for primary vaccination, in accordance with the recommended timing for the booster of the inactivated Japanese encephalitis vaccine.

In adults, there is no need for a booster dose up to 5 years after the administration of a single dose of Encephalitis Vaccine. Once the freeze-dried vaccine has been completely reconstituted using the diluent provided, it is administered via the subcutaneous route.

In persons 2 years of age and over, the recommended injection site is the deltoid region of the upper arm.

In persons between 9 and 24 months of age, the recommended injection site is the anterolateral aspect of the thigh or the deltoid region. Do not administer by intravascular injection. Encephalitis Vaccine must not be mixed with any other injectable vaccine(s) or medicinal product(s). Contact with disinfectants is to be avoided since they may inactivate the vaccine virus.

Encephalitis Vaccine should not be administered to anyone with a history of severe allergic reaction to any component of the vaccine or history of severe allergic reaction after previous administration of the vaccine or a vaccine containing the same components or constituents. Vaccination must be postponed in case of febrile or acute disease. Congenital or acquired immune deficiency impairing cellular immunity, including immunosuppressive therapies such as chemotherapy, high doses of systemic corticosteroids given generally for 14 days or more.

Encephalitis Vaccine must not be administrated to persons with symptomatic HIV infection or with asymptomatic HIV infection when accompanied by evidence of impaired immune function.

Very common side effects are tiredness (fatigue), feeling unwell (malaise), injection site pain, Headache,  Muscular pain (myalgia).

Use in pregnancy: Animal studies did not indicate direct or indirect harmful effects with respect to pregnancy, embryo-fetal development, parturition or post-natal development. As with all live attenuated vaccines, pregnancy constitutes a contra-indication

Use in lactation: Animal studies did not indicate direct or indirect harmful effects with respect to lactation. It is not known whether this vaccine is excreted in human milk. Encephalitis Vaccine vaccination is contraindicated in breastfeeding women

As with all injectable vaccines, appropriate medical treatment and supervision should always be readily available in case of a rare anaphylactic event following administration of the vaccine. For patients following a treatment with high doses of systemic corticosteroids given for 14 days or more, it is advisable to wait for at least one month or more following the interruption of therapy before carrying out the vaccination until immune function has recovered. Encephalitis Vaccine should under no circumstances be administered intravascularly.

Keep out of reach and sight of children. Store in a refrigerator (2°C–8°C). Do not freeze. Keep the vials in the outer carton in order to protect from light.