The purpose of this study is to assess the safety of a vaccination schedule consisting of two vaccinations (21-35 days apart) with the tick-borne encephalitis (TBE) vaccine FSME-IMMUN NEW (5 consecutive lots) in comparison to another licensed TBE vaccine (Encepur® adults, with polygeline) (2 lots) in healthy volunteers aged 16 to 65 years.

Inclusion Criteria:

Male and female volunteers were eligible for participation in this study if they:

• Were 16 years (from the 16th birthday) to 65 years (to the last day before the 65th birthday) old
• Were clinically healthy
• Had a negative pregnancy test at the first medical examination, if female and capable of bearing children
• Agreed to employ adequate birth control measures for the duration of the study, if female and capable of bearing children
• Provided written informed consent
• For volunteers under 18 years of age - written informed consent of the parents / guardian was available
• Agreed to keep a volunteer diary

Exclusion Criteria:

• History of any previous TBE vaccination
• History of TBE infection or show evidence of latent TBE infection (as demonstrated by screening ELISA > 126 VIEU/ml)
• History of allergic reactions, in particular to one of the components of the vaccine
• Previously received volume substitution with a product containing polygeline (stabilizer in ENCEPUR)
• Received antipyretics within 4 hours prior to the first TBE vaccination
• Suffer from a disease that cannot be effectively treated or stabilized
• Suffering from a disease (e.g. autoimmune disease) or were undergoing any form of treatment that could be expected to influence immunological functions
• Suffering from chronic, degenerative and/or inflammatory disease of the central nervous system
• Using any immunosuppressive drugs (e.g. local or systemic corticosteroids, chemotherapeutics)
• Had a known or suspected problem with drug or alcohol abuse (> 4 liters wine / week or equivalent level of other alcoholic beverages)
• Had donated blood or plasma within one month of the study start
• Had received banked blood or immunoglobulins within one month of study entry
• Known to be HIV positive (a special HIV test was not required for the purpose of the study)
• Suffering from a febrile illness at study entry
• History of vaccination against yellow fever and / or Japanese B encephalitis
• Participating simultaneously in another clinical trial
• If female: pregnant or breast feeding