Safety Study of 2 Formulations of GSK's Human Rotavirus (HRV) Vaccine (444563), in Healthy Infants Starting at Age 6-12 Weeks

Inclusion Criteria: All subjects must satisfy all the following criteria at study entry: * Subjects' parent(s)/LAR(s) who, in the opinion of the investigator, can and will comply, with the requirements of the protocol (e.g. completion of the diary cards, return for follow-up visits). * Written or witnessed/thumb printed informed consent obtained from the parent(s)/LAR(s) of the subject prior to performance of any study specific procedure. * Healthy subjects as established by medical history and clinical examination before entering into the study. * A male or female between, and including, 6 and 12 weeks (42-90 days) of age at the time of the first vaccination. Exclusion Criteria: Medical conditions * Uncorrected congenital malformation (such as Meckel's diverticulum) of the gastrointestinal tract that would predispose for Intussusception (IS). * Very prematurely born infants (born ≤28 weeks of gestation). * History of IS. * Family history of congenital or hereditary immunodeficiency. * Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination (no laboratory testing required). * Hypersensitivity to latex. * Major congenital defects or serious chronic illness, as assessed by the investigator. * Previous confirmed occurrence of Rotavirus Gastroenteritis (RV GE). * History of any reaction or hypersensitivity likely to be exacerbated by any component of the vaccines. * History of Severe combined immunodeficiency (SCID). Prior/Concomitant therapy * Use of any investigational or non-registered product (drug, vaccine or medical device) other than the study vaccines during the period starting 30 days before the first dose of study vaccines (Day -29 to Day 1), or planned use during the study period. * Planned administration/administration of a vaccine not foreseen by the study protocol in the period starting 30 days before the first dose and ending 30 days after the last dose of study vaccine administration, with the exception of the inactivated influenza vaccine, which is allowed at any time during the study, and other licensed routine childhood vaccinations. * Administration of long-acting immune-modifying drugs at any time during the study period (e.g. infliximab). * Administration of immunoglobulins and/or any blood products from birth or planned administration during the study period. * Chronic administration (defined as more than 14 days in total) of immunosuppressants or other immune-modifying drugs since birth. For corticosteroids, this will mean prednisone ≥0.5 mg/kg/day, or equivalent. Inhaled and topical steroids are allowed. * Previous vaccination against RV. Prior/Concurrent clinical study experience * 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 vaccine/product (drug or medical device). Other exclusions • Child in care.