Safety and Immunogenicity of MT-5625 in Healthy Adults, Toddlers and Infants

Inclusion Criteria: * Healthy male or female adults/toddlers/infants as established by medical history and clinical examination before entering the study * Adults aged \>18 and \< 35, toddlers aged \>12 and \< 24 months, and infants aged \> 6 and \< 10 weeks at the time of enrollment * Subject (or Parent/Legal Guardian) willing and able to give written informed consent after the nature of the study has been explained * Subject (or Parent/Legal Guardian) willing to comply with the study restrictions and study schedule and to remain in the area for the study duration * Females of potential childbearing must not be pregnant or breastfeeding and willing to use adequate method of contraception during the trial Exclusion Criteria: ALL SUBJECTS * Presence of fever or other acute illness * Concurrent participation in another clinical trial or receipt of an investigational product during the 30 days prior to randomization * Suspected or known impairment of immune function * Known sensitivity to any components of the study vaccine * History of anaphylactic reaction * Receipt of immunoglobulin therapy or blood products in last 6 months * History of chronic immunosuppressive medications (with the exception of inhaled or topical steroids) * History of any clinically significant disease or disorder which, in the opinion of the Investigator, may either put the volunteer at risk because of participation in the study, or influence the results or the volunteer's ability to participate in the study ADULTS ONLY * Have received any vaccine within 4 weeks prior to randomization * Any clinically significant illness, medical/surgical procedure, or trauma within 4 weeks of the first administration of investigational product (IP) * Any clinically significant abnormalities on 12-lead ECG as judged by the Investigator * Any positive result on screening for serum hepatitis B surface antigen, hepatitis C antibody, and human immunodeficiency virus (HIV) antibody * Have any contraindications to parenteral injections ( eg history of bleeding disorder) * Known or suspected history of alcohol or drug abuse or excessive intake of alcohol as judged by the Investigator * Donated blood within the 4 weeks prior to randomization TODDLERS and INFANTS * Received any vaccine within 14 days of randomization * Presence of malnutrition or other systemic disorders * History of congenital abdominal disorders, intussusception or abdominal surgery * Major congenital or genetic defect TODDLERS ONLY * Any positive result on screening for serum hepatitis B surface antigen, hepatitis B core antibody, hepatitis C antibody, and human immunodeficiency virus (HIV) antibody. INFANTS ONLY * Infants with history of premature birth (\<37 weeks gestational age) * Infants who have received rotavirus vaccine in the past * Known sensitivity to any components of the study vaccine, including Rotarix® * Any positive result on screening for serum hepatitis B surface antigen, hepatitis B core antibody, and hepatitis C antibody * HIV infection assessed by PCR if mother is not known to be negative (negative test result between 24 weeks gestation and screening).