A Clinical Trial of CSL's 2010/2011 Formulation of Enzira® in a Healthy Adult Population

• The Percentage of Evaluable Participants Achieving Seroconversion or Significant Increase in Antibody Titre. [ Time Frame: Approximately 21 days after vaccination ] [ Designated as safety issue: No ]
  As per the criteria specified in the CPMP/BWP/214/96 Note for Guidance on Harmonisation of Requirements for Influenza Vaccines. For haemagglutination inhibition (HI), seroconversion is defined as achieving a post-vaccination titre of ≥ 40 for those participants with a pre-vaccination HI titre of < 10; significant increase is defined as a four-fold or greater increase in HI titre for those participants with a pre-vaccination HI titre of ≥ 10.
• The Geometric Mean Fold Increase (GMFI) in Antibody Titre After Vaccination. [ Time Frame: Approximately 21 days after vaccination ] [ Designated as safety issue: No ]
  GMFI is defined as the geometric mean of the fold increases of post-vaccination antibody titre over the pre-vaccination antibody titre.
• The Percentage of Evaluable Participants Achieving a HI Titre ≥ 40 or Single Radial Haemolysis (SRH) Area ≥ 25 mm2. [ Time Frame: Approximately 21 days after vaccination ] [ Designated as safety issue: No ]

• Frequency of Any Solicited Adverse Events (AEs) [ Time Frame: During the 4 days after vaccination (Day 0 plus 3 days) ] [ Designated as safety issue: Yes ]
  The number of participants reporting any solicited AEs.
• Frequency and Intensity of Any Unsolicited Adverse Events [ Time Frame: After vaccination until the end of the study; approximately 21 days ] [ Designated as safety issue: Yes ]

  Unsolicited adverse event (UAE) grading:

  Mild: Symptoms were easily tolerated and there was no interference with daily activities. Moderate: Enough discomfort to have caused some interference with daily activities. Severe: Symptoms that prevented normal, everyday activities.

• Frequency, duration and intensity of solicited adverse events [ Time Frame: During the 3 days after vaccination ] [ Designated as safety issue: Yes ]
• Frequency, duration and intensity of unsolicited adverse events [ Time Frame: During the 21 days after vaccination ] [ Designated as safety issue: Yes ]

The purpose of this study is to determine whether the 2010/2011 Formulation Enzira vaccine is safe and elicits an immune response to seasonal influenza in healthy adults.

• Experimental: Adults
  Healthy volunteers aged 18 to 59 years
  Intervention: Biological: CSL's 2010/2011 Formulation of Enzira® Vaccine
• Experimental: Older Adults
  Healthy volunteers aged 60 years or older
  Intervention: Biological: CSL's 2010/2011 Formulation of Enzira® Vaccine

Inclusion Criteria:

• Male or female aged 18 years and older at the time of the first study vaccination.

Exclusion Criteria:

• Known hypersensitivity to a previous dose of influenza virus vaccine or allergy to eggs, chicken protein, neomycin, polymyxin, or any components of the Study Vaccine.
• Clinical signs of an active infection
• Vaccination with a seasonal or experimental influenza virus vaccine in the 6 months preceding study entry
• Females who are pregnant or lactating