Safety and Immunogenicity of 3 Lots of Cell-derived Subunit Influenza Vaccine as Compared to 1 Lot to Egg-derived Subunit Influenza Vaccine in Healthy Adults (>=18 to <=60)

Inclusion criteria

• 18 to <61 years of age
• mentally competent to understand the nature, the scope and the consequences of the study
• able and willing to give written informed consent prior to study entry
• in good health as determined by:

• medical history,
• physical examination,
• clinical judgment of the Investigator.

Exclusion criteria

• unwilling or unable to give written informed consent to participate in the study
• participation in another clinical trial of an investigational agent within 90 days prior to Visit 1 and throughout the entire study
• currently experiencing an acute infectious disease
• any serious disease, such as, for example:

• cancer,
• autoimmune disease (including rheumatoid arthritis),
• advanced arteriosclerotic disease or complicated diabetes mellitus,
• chronic obstructive pulmonary disease (COPD) requiring oxygen therapy,
• acute or progressive hepatic disease,
• acute or progressive renal disease,
• congestive heart failure
• surgery planned during the study period
• bleeding diathesis
• history of hypersensitivity to any component of the study medication or chemically related substances
• history of any anaphylaxis, serious vaccine reactions, or allergy to any of the vaccine component
• known or suspected impairment/alteration of immune function, for example resulting from:

• receipt of immunosuppressive therapy (any corticosteroid therapy or cancer chemotherapy),
• receipt of immunostimulants,
• receipt of parenteral immunoglobulin preparation, blood products, and/or plasma derivates within 3 months prior to Visit 1 or planned during the full length of the study,
• high risk for developing an immunocompromising disease
• history of drug or alcohol abuse
• laboratory-confirmed influenza disease within 6 months prior to Visit 1
• receipt of influenza vaccine within 6 months prior to Visit 1
• receipt of another vaccine within 60 days prior to Visit 1, or planned vaccination within 3 weeks following study vaccination
• any acute respiratory disease or infections requiring systemic antibiotic or antiviral therapy (chronic antibiotic therapy for urinary tract prophylaxis is acceptable) or experienced fever (i.e., axillary temperature ≥ 38 degree C) within 5 days prior to Visit 1
• if female, pregnant or breastfeeding
• if female, refusal to use a reliable contraceptive method during the three weeks following vaccination
• planned relocation abroad during the study period
• any condition that, in the opinion of the Investigator, might interfere with the evaluation of the study objectives.