Thirty healthy two-year old children were prospectively randomized to receive either 2 doses (separated by 2 months) of a pentavalent (serotypes 6B, 14, 18C, 19F and 23) pneumococcal CRM197 protein conjugated (CRM-PS) vaccine or one dose of pneumococcal polysaccharide (PS) vaccine as comparator. Fever, behavior change and injection site reactions were assessed for 4 days post-vaccine. There were no significant adverse effects. For all serotypes except 18C, CRM-PS vaccines was significantly more immunogenic than PS vaccines as measured by mean fold antibody rise and/or four-fold seroresponse:Table A 4-fold seroresponse after two doses of CRM-PS vaccine which was significantly different than after PS vaccine was seen for 95% (p=0.0003), 84% (p=0.02), 100% (p=0.38), 74% (p=0.04) and 95% (p=0.04) of children for serotypes 6B, 14, 18C, 19F and 23, respectively. These results encourage further study of this conjugate pneumococcal vaccine in infants. Sponsored by NIH/NIAID.

Table 1
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