The Efficacy in Navajo Infants of a Conjugate Vaccine Consisting ofHaemophilus influenzaeType b Polysaccharide andNeisseria meningitidisOuter-Membrane Protein Complex

Abstract

Several conjugate vaccines against Haemophilus influenzae type b have been developed in the search for one that induces protection even in young infants. We evaluated the safety and efficacy of a conjugate vaccine that links the H. influenzae type b capsular polysaccharide to the outer-membrane protein complex (OMPC) of Neisseria meningitidis serogroup B. We conducted a double-blind, placebo-controlled trial in Navajo infants, who are at high risk for systemic infections caused by H. influenzae type b. The infants were randomly assigned to receive the first dose of vaccine or placebo at 42 to 90 days of age and the second at 70 to 146 days of age.