Dose-finding Study to Evaluate Immunogenicity of Three Different Dose Levels of the IMVAMUNE (MVA-BN) Smallpox Vaccine.

Inclusion Criteria: Healthy male and female subjects, aged 18 - 30 years Signed informed consent after being advised of the risks and benefits of the study in a language able to understand, and prior to performance of any study specific procedure. Free of obvious health problems with acceptable medical history by screening evaluation and physical examination. Subject of not of child-bearing potential or all of the following: A urine/serum ß-HCG pregnancy test gives a negative result, use of adequate contraceptive precautions for 30 days before first vaccination. Exclusion Criteria: Known or suspected history of smallpox vaccination or typical vaccinia scar. Positive test result in MVA specific ELISA or PRNT at screening. Positive result in HIV or HCV antibody test at screening. HbsAG positive at screening. Pregnancy or breast-feeding. Uncontrolled serious infection i.e. not responding to antimicrobial therapy History of any serious medical condition, which in the opinion of the investigator, would compromise the safety of the subject. History of autoimmune disease History of malignancy. History of chronic alcohol abuse and/or intravenous drug abuse. History of allergic disease or reactions likely to be exacerbated by any component of the vaccine. History of anaphylaxis or severe allergic reaction. Acute disease (a moderate or severe illness with or without a fever) at the time of enrolment. Any vaccinations within a period starting 30 days prior to administration of the vaccine and ending at study conclusion. Chronic administration of immuno-suppressants or other immune-modifying drugs. Administration or planned administration of immunoglobulins and/or any blood products during the study period. Use of any investigational or non-registered drug or vaccine.