Currently in the UK, 3 doses of a vaccine called Prevenar 13 (PCV-13), which contains 13 pneumococcal serotypes attached to a carrier protein called CRM197, are given to children at 2, 4 and 12 months of age. There is some evidence that a vaccine called Synflorix (PHiD-CV) may be at least as good as the currently used vaccine when used as an alternative vaccine at 12 months of age. Although PHiD-CV contains only 10 serotypes, there is evidence that it generates cross-reactive antibodies against two of the three additional serotypes included in PCV-13 which might be enough to protect children against disease caused by these two serotypes. Furthermore, previous studies have shown that PHiD-CV confers protection against a common otitis media pathogen in children called nontypeable H. influenzae (NTHi) by attachment to a carrier protein called Protein D, which is derived from NTHi. In addition, the use of a carrier protein, which is not closely related to an antigen included in any coadministered or previously administered routine vaccine minimises the risk of interference related to it.~The investigators aim to recruit 168 healthy children at the age of 12 months who have already received two doses of PCV-13 according to the UK routine immunisation schedule at 2 and 4 months of age. Participants will then be randomised to receive a booster dose of either PCV-13 or PHiD-CV at 12 months of age.~Three visits will take place at their parents' home and will involve a blood test followed by a dose of PCV-13 or PHiD-CV on visit 1, and a blood test on each of the visits 2 (1 month after visit 1) and 3 (1 year after visit 1).
This is a study to evaluate an alternative booster for pneumococcal conjugate vaccination (PCV) for children at 12 months of age. Currently in the UK, 3 doses of a vaccine called Prevenar 13 (PCV-13), which contains 13 pneumococcal serotypes attached to a carrier protein called CRM197, are given to children at 2, 4 and 12 months of age. There is some evidence that a vaccine called Synflorix (PHiD-CV) may be at least as good as the currently used vaccine when used as an alternative vaccine at 12 months of age. Although PHiD-CV contains only 10 serotypes, there is evidence that it generates cross-reactive antibodies against two of the three additional serotypes included in PCV-13 which might be enough to protect children against disease caused by these two serotypes. Furthermore, previous studies have shown that PHiD-CV confers protection against a common otitis media pathogen in children called nontypeable H. influenzae (NTHi) by attachment to a carrier protein called Protein D, which is derived from NTHi. In addition, the use of a carrier protein, which is not closely related to an antigen included in any coadministered or previously administered routine vaccine minimises the risk of interference related to it.~The investigators aim to recruit 168 healthy children at the age of 12 months who have already received two doses of PCV-13 according to the UK routine immunisation schedule at 2 and 4 months of age. Participants will then be randomised to receive a booster dose of either PCV-13 or PHiD-CV at 12 months of age.~Three visits will take place at their parents' home and will involve a blood test followed by a dose of PCV-13 or PHiD-CV on visit 1, and a blood test on each of the visits 2 (1 month after visit 1) and 3 (1 year after visit 1).