Children with HIV infection are at increased risk for invasive pneumococcal infection, particularly bacteremia. A large proportion of pneumococcal disease is caused by a limited number of serotypes. The maximum number of pneumococcal serotypes that can be included in a new conjugate vaccine is felt to be limited by the amount of carrier protein. A heptavalent pneumococcal conjugate vaccine has been developed that consists of pneumococcal capsular saccharides from serotypes 4, 6B, 9V, 14, 18C, 19F, and 23F bound to a diphtheria toxin mutant carrier protein.
Infants are randomized to receive either heptavalent pneumococcal conjugate vaccine or placebo by intramuscular injection at study months 0, 2, and 4, and then at 15 months of age. Additionally, patients receive PNU-IMUNE 23 ( pneumococcal polyvalent vaccine ) at 24 months of age.