Study to Evaluate Immunogenicity, Reactogenicity and Safety of Rotarix™ Vaccine in Korean Infants

• Serum Anti-rotavirus Immunoglobulin A Antibody Concentrations [ Time Frame: One month after the second vaccine dose ] [ Designated as safety issue: No ]
  Concentrations are given as Geometric Mean Concentrations (GMCs). Note: In the Placebo Group the value was below the assay cut-off (20 units per milliliter).
• Number of Subjects Reporting Solicited Symptoms [ Time Frame: During the 8-day (Day 0 - Day 7) follow-up period after each vaccine dose. ] [ Designated as safety issue: No ]
  Solicited symptoms assessed include cough, diarrhoea, irritability, loss of appetite , fever and vomiting.
• Number of Subjects Reporting Unsolicited Adverse Events (AEs) [ Time Frame: During the 31-day (Day 0 - Day 30) follow-up period after each vaccine dose ] [ Designated as safety issue: No ]
  Unsolicited AE covers any AE reported in addition to those solicited during the clinical study and any solicited symptom with onset outside the specified period of follow-up for solicited symptoms.
• Number of Subjects Reporting Serious Adverse Events (SAEs) [ Time Frame: Throughout the study period (2-3 months). ] [ Designated as safety issue: No ]
  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.
• Number of Subjects Reporting Rotavirus Gastroenteritis Episode(s) [ Time Frame: From Dose 1 up to 1 month after Dose 2. ] [ Designated as safety issue: No ]

• Immunogenicity to study vaccine antigen on secondary readouts [ Time Frame: One month after the second vaccine dose ] [ Designated as safety issue: No ]
• Immunogenicity to study vaccine antigen observed in this study with the immunogenicity to study vaccine antigen observed in the study NCT00140673. [ Designated as safety issue: No ]
• Occurrence of each type of solicited symptom [ Time Frame: During the 8-day (Day 0 - Day 7) follow-up period after each vaccine dose. ] [ Designated as safety issue: No ]
• Occurrence of unsolicited adverse event (AE) [ Time Frame: During the 31-day (Day 0 - Day 30) follow-up period after each vaccine dose ] [ Designated as safety issue: No ]
• Occurrence of serious adverse events (SAEs) [ Time Frame: Throughout the study period (3 months). ] [ Designated as safety issue: No ]
• Presence of rotavirus (RV) in Gastroenteritis (GE) stool samples. [ Time Frame: From Dose 1 up to 1 month after Dose 2. ] [ Designated as safety issue: No ]

The aim of this study is to assess the immunogenicity, reactogenicity and safety of the human rotavirus (HRV) Rotarix ™ vaccine when administered in healthy infants aged approximately 6-12 weeks at the time of first vaccination.

• Rotavirus Infection
• Rotavirus Gastroenteritis

• Biological: Rotarix ™
  Two oral doses
• Biological: Placebo
  Two oral doses

• Experimental: Rotarix Group
  Subjects received 2 oral doses of Rotarix according to a 0, 1 or 2-month schedule.
  Intervention: Biological: Rotarix ™
• Placebo Comparator: Placebo Group
  Subjects received 2 oral doses of placebo according to a 0, 1 or 2-month schedule.
  Intervention: Biological: Placebo

Inclusion Criteria:

• Subjects who the investigator believes that their parents/guardians can and will comply with the requirements of the protocol should be enrolled in the study.
• A male or female between, and including, 6 to 12 weeks of age at the time of the first dose of the vaccination.
• Written informed consent obtained from the parents or guardians of the subject.
• Healthy subjects as established by medical history and clinical examination before entering into the study.
• Born after a normal gestation period of between 37 and 41 weeks + 6 days inclusive.
• Subjects for whom the vaccination history is available from vaccination diary cards or medical charts.

Exclusion Criteria:

• Use of any investigational or non-registered product (drug or vaccine) other than the study vaccine(s) within 30 days preceding the dose of study vaccine, or planned use during the study period.
• Chronic administration (defined as more than 14 days) of immunosuppressants or other immune-modifying drugs since birth.
• Planned administration/ administration of a vaccine not foreseen by the study protocol within 30 days of the first dose of vaccine with the exception of the routine infant vaccines.
• Concurrently participating in another clinical study, at any time during the study period, in which the subject has been or will be exposed to an investigational or a non-investigational product.
• Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination.
• Any clinically significant history of chronic gastrointestinal disease including any uncorrected congenital malformation of the gastrointestinal tract or other serious medical condition as determined by the investigator.
• History of allergic disease or reactions likely to be exacerbated by any component of the vaccine.
• Acute disease at the time of enrolment.
• Administration of immunoglobulins and/or any blood products since birth or planned administration during the study period.
• Gastroenteritis (GE) within 7 days preceding the study vaccine administration.
• Previous confirmed occurrence of RV GE.
• Previous vaccination with rotavirus vaccine or planned use during the study period.