The safety of DTaP-HepB-IPV vaccine coadministered with PCV and Hib was compared with separate administration of DTaP, HepB, IPV, Hib, and PCV at 2, 4, and 6 months of age. Healthy 2-month-old infants (N=1008) were randomized to the two groups. Following dose 1, there was no significant difference between the groups in the incidence of fever >101.3 degrees F. After each dose, the incidence of any fever (> or =100.4 degrees F) was significantly higher in the Combination Vaccine Group. The rate of fever >103.1 degrees F was < or =1.4% in both groups after any of the doses. Medical advice visits for fever were infrequent in both groups (< or =1.2%). DTaP-HepB-IPV was safe and well tolerated when coadministered with PCV and Hib.