Safety and Immune Response Study of GSK Biologicals' Influenza Virus Vaccine 1388442A Compared With Fluarix

• Number of Subjects With Solicited Local Symptoms. [ Time Frame: During the 7-day (Days 0-6) post vaccination period ] [ Designated as safety issue: No ]
  Solicited local symptoms were pain, redness and swelling at the injection site. Any = occurrence of a symptom regardless of intensity.
• Number of Subjects With Solicited General Symptoms. [ Time Frame: During the 7-day (Days 0-6) post vaccination period ] [ Designated as safety issue: No ]
  Solicited general symptoms were arthralgia, fatigue, headache, muscle aches, shivering and temperature, assessed as oral temperature above or equal (≥) 38.0 degrees Celsius (°C). Any = occurrence of a symptom regardless of intensity or relationship to vaccination.
• Number of Subjects With Medically Attended Adverse Events (MAEs). [ Time Frame: During the entire study period (Days 0-182) ] [ Designated as safety issue: No ]
  Medically-attended events (MAEs) refer to non-serious and serious events leading to an otherwise unscheduled visit to or from medical personnel for any reason, including emergency room visits and hospitalization. Related MAE = MAE assessed by the investigator as related to the vaccination.
• Number of Subjects With New Onset of Chronic Diseases (NOCDs). [ Time Frame: During the entire study period (Days 0-182) ] [ Designated as safety issue: No ]
  NOCDs include conditions such as autoimmune disorders, asthma, type I diabetes, or allergies.
• Number of Subjects With Unsolicited Adverse Events (AEs). [ Time Frame: During the 90-day (Days 0-89) post-vaccination period ] [ Designated as safety issue: No ]
  Unsolicited AEs cover any untoward medical occurrence in a clinical investigation subject, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. Any unsolicited AE = any unsolicited AE regardless of intensity or relationship to vaccination.
• Number of Subjects With Serious Adverse Events (SAEs). [ Time Frame: During the entire study period (Days 0-182) ] [ Designated as safety issue: No ]
  Serious adverse events (SAEs) assessed include medical occurrences that result in death, are life threatening, require hospitalization or prolongation of hospitalization, result in disability/incapacity or are a congenital anomaly/birth defect in the offspring of a study subject. Any SAE = any SAE regardless of intensity or relationship to vaccination.
• Titers for Serum Hemagglutination Inhibition (HI) Antibodies for 3 Strains of Influenza Disease. [ Time Frame: At Day 21 ] [ Designated as safety issue: No ]
  Titers are presented as geometric mean titers (GMTs). The 3 influenza strains assessed were A/Solomon Islands/3/2006 (H1N1), A/Wisconsin/67/2005 (H3N2) and B/Malaysia/2506/2004 (MALAY.)
• Number of Seroprotected Subjects Against 3 Strains of Influenza Disease. [ Time Frame: At Day 21 ] [ Designated as safety issue: No ]
  A seroprotected subject was defined as a vaccinated subject with a serum HI antibody titer ≥ 1:40, a level of HI antibody that has been viewed as correlating with protection against influenza. The 3 influenza strains assessed were A/Solomon Islands/3/2006 (H1N1), A/Wisconsin/67/2005 (H3N2) and B/Malaysia/2506/2004 (MALAY.)
• Number of Seroconverted Subjects Against 3 Strains of Influenza Disease. [ Time Frame: At Day 21 ] [ Designated as safety issue: No ]
  A seroconverted subject was defined as a vaccinated subject who had either a pre-vaccination titer <1:10 and a post-vaccination titer ≥1:40 or a pre-vaccination titer ≥1:10 and at least a four-fold increase in post-vaccination titer. The 3 influenza strains assessed were A/Solomon Islands/3/2006 (H1N1), A/Wisconsin/67/2005 (H3N2) and B/Malaysia/2506/2004 (MALAY.)
• Geometric Mean Fold-rise (GMFR) in 3 Strains of Influenza Disease. [ Time Frame: At Day 0 and Day 21 ] [ Designated as safety issue: No ]
  GMFR was defined as the geometric mean of the ratio of the post-vaccination inverse HI titer to the Day 0 inverse HI titer. The 3 influenza strains assessed were A/Solomon Islands/3/2006 (H1N1), A/Wisconsin/67/2005 (H3N2) and B/Malaysia/2506/2004 (MALAY.)

• Occurrence of specifically-solicited local and general signs and symptoms. [ Time Frame: During a 7-day follow-up period after vaccination. ]
• Occurrence of serious adverse events, medically attended AEs, and NOCDs. [ Time Frame: During the entire study period (Day 0 to 180). ]
• Occurrence of unsolicited adverse events. [ Time Frame: During the 90-day period after vaccination. ]
• Influenza A and B antibody titers (GMT, SPR, SCR, GMFR). [ Time Frame: On Days 0 and 21 ]

The purpose of the study is to compare the safety of & immune response to a single dose of GSK Biologicals' cell-culture based influenza vaccine 138842A with that of a US licensed, egg-based trivalent influenza vaccine [Fluarix] in healthy adults.

• Influenza Vaccines
• Seasonal Influenza

• Biological: Trivalent influenza vaccine GSK 138842A
  IM injection on Day 0
• Biological: Fluarix
  IM injection on Day 0

• Experimental: GSK 1388442A Group
  Subjects aged 18 to 49 years of age at the time of vaccination received 1 dose of GSK 1388442A vaccine at Day 0. The GSK 1388442A vaccine was administered intramuscularly in the deltoid region of the non-dominant arm.
  Intervention: Biological: Trivalent influenza vaccine GSK 138842A
• Active Comparator: Fluarix Group
  Subjects aged 18 to 49 years of age at the time of vaccination received 1 dose of Fluarix® vaccine at Day 0. The Fluarix® vaccine was administered intramuscularly in the deltoid region of the non-dominant arm.
  Intervention: Biological: Fluarix

Inclusion Criteria:

• Subjects who the investigator believes can and will comply with the requirements of the protocol
• A male or non-pregnant, non-lactating female between 18 and 49 years of age at the time of vaccination
• Access to a telephone for scheduled follow-up telephone contacts
• Ability to provide written informed consent
• Healthy subjects as established by medical history and physical examination before entering into the study
• If the subject is female, she must be of non-childbearing potential, or if she is of childbearing potential, she must practice adequate contraception for 30 days prior to vaccination and continue such precautions for 2 months after receipt of the study vaccine. All women will have a pregnancy test on the day of vaccination.

Exclusion Criteria:

• Use of any investigational or non-registered product (drug or vaccine) other than the study vaccine within 30 days preceding the dose of study vaccine, or planned use during the study period
• Receipt of systemic glucocorticoids within 30 days of study enrollment
• Administration of immunosuppressant, cytotoxic, or other immune-modifying drugs (other than glucocorticoids) or irradiation within 6 months prior to study enrollment or planned administration during the study period
• Administration of immunoglobulins and/or blood products within 3 months prior to study enrollment or planned administration during the study period
• Previous vaccination against influenza (2007-2008 influenza season)
• History of anaphylactic or other allergic reaction to influenza vaccine, any other vaccine, or any vaccine component or excipient
• History of Guillain-Barre Syndrome (GBS)
• Acute disease, febrile illness, or upper respiratory infection at screening.
• History of splenectomy
• Any confirmed or suspected, acquired, congenital, or hereditary immunodeficiency or immunosuppressive condition (including human immunodeficiency virus [HIV]) based on medical history and physical examination
• Acquired or congenital coagulation disorders or known thrombocytopenia
• Current treatment with warfarin or heparin derivatives
• Known use of an analgesic or antipyretic medication within 12 hours prior to treatment for the purposes of prophylaxis of adverse events
• Any medical condition for which the US Advisory Committee on Immunization Practices recommends vaccination against influenza