Consistency of Immunogenicity and Non Inferiority of GSK Biologicals' Candidate Malaria Vaccine Lots in Children

Inclusion Criteria: * Subjects who the investigator believes that their parent(s)/Legally Acceptable Representative(s) (LAR) can and will comply with the requirements of the protocol. * A male or female child between, and including, 5 and 17 months of age at the time of the first vaccination. * Signed or thumb-printed informed consent obtained from the parent(s)/LAR(s) of the child. Where parent(s)/LAR(s) are illiterate, the consent form will be countersigned by a witness. * Healthy subjects as established by medical history and clinical examination before entering into the study. * Subjects who have received three documented doses of hepatitis B vaccine. Exclusion Criteria: * Same sex twins. * Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination. * Family history of congenital or hereditary immunodeficiency. * History of any reaction or hypersensitivity likely to be exacerbated by any component of the vaccine. * Major congenital defects or serious chronic illness. * History of any neurological disorders or seizures. * Moderate or severe malnutrition at screening defined as weight for age Z-score less than 2. * Acute disease and/or fever at the time of enrolment * Acute or chronic, clinically significant pulmonary, cardiovascular, hepatic or renal functional abnormality, as determined by physical examination or medical history. * Use of a drug or vaccine that is not approved for that indication other than the study vaccines within 30 days preceding the first dose of study vaccine, or planned use during the study period. * Chronic administration of immunosuppressants or other immune-modifying drugs since birth. * Planned administration/administration of a licensed vaccine not foreseen by the study protocol within 7 days of the first dose of study vaccine. * 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. * Administration of immunoglobulins and/or any blood products within 1 month preceding the first dose of study vaccine or planned administration during the study period. * Child in care. * Any other findings that the investigator feels would increase the risk of having an adverse outcome from participation in the trial.