• Severe RV GE by wild-type G1, non-G1, each non-G1, 11 score after Dose 2 and Dose 1 until 1-year old.
• Severe RV GE in subset during the 2nd year and both years.
• SAEs.
• Definite IS until 1-year old and 2-years old.
• Serum anti-RV IgA at Visits 1 and 3 (subset/country except Finland).

The main objectives of this study are: 1) In a subset (N = 20 000), to determine vaccine efficacy against severe rotavirus (RV) gastroenteritis (GE) during the period starting from 2 weeks after Dose 2 until one year of age. 2) In all subjects (N = 60 000), to determine the safety of GSK Biologicals’ HRV vaccine with respect to definite intussusception (IS) within 31 days (Day 0-Day 30) after each HRV vaccine dose.

• The study has two groups: Group HRV and Group Placebo. Two oral doses administered to healthy infants who are 6-13 weeks of age at the time of Dose 1, according to a 0, 1 to 2-month schedule. Routine EPI vaccinations are given at the discretion of the investigator and according to local National Plans of Immunisation schedule in each participating country. A minimum 2-week interval was to be observed between HRV vaccine and OPV doses. Of the total enrolled cohort of 60 000 subjects, 20 000 subjects were followed for efficacy and safety until one year of age while 40 000 subjects were followed for safety only until 30-90 days after the second HRV/placebo dose. A subset (N = approximately 13 000) of the 20 000 subjects are followed for efficacy and safety until 24 months of age. From the 20 000 subjects followed for efficacy and safety, a subset of 100 subjects per country (center specific, except Finland) provided two blood sample to evaluate immunogenicity.

Inclusion criteria:

• Healthy infants 6-13 weeks of age at the time of the first study vaccination whose parent/guardian sign a written informed consent and whose parents/guardians can and will comply with the requirements of the protocol (e.g., completion of the diary cards, return for follow-up visits)

Exclusion criteria:

• Use of any investigational or non-registered product (drug or vaccine) other than the study vaccine(s) within 30 days preceding the first dose of study vaccine or placebo, or planned use during the study period
• Chronic administration (defined as more than 14 days) of immunosuppressants or other immune-modifying drugs since birth. (Topical steroids are allowed.)
• Child is unlikely to remain in the study area for the duration of the study
• Any confirmed or suspected immunosuppressive or immunodeficient condition, including human immunodeficiency virus (HIV) infection
• History of allergic disease or reaction likely to be exacerbated by any component of the vaccine
• Administration of immunoglobulins and/or blood products since birth or planned administration during the study period
• 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