A new DTPw-HBV/Hib vaccine is immunogenic and safe when administered according to the EPI (Expanded Programme for Immunization) schedule and following hepatitis B vaccination at birth

Abstract

New combination vaccines and reliable sources of vaccine components are essential to ensure the success of mass immunisation programmes in the 21st century. We evaluated a new combined diphtheria-tetanus-whole-cell-pertussis-hepatitis B vaccine, extemporaneously mixed with a Haemophilus influenzae type b conjugate vaccine (DTPw-HBV/Hib) containing 2.5 microg PRP in 913 Philippino infants, administered according to the EPI schedule at 6, 10 and 14 weeks of age after a birth dose of hepatitis B vaccine (HBV; trial DTPw-HBV/Hib-001). One month after the third dose of DTPw-HBV/Hib (N = 182), 99.4% and 94.2% of subjects had anti-PRP antibody levels > or =0.15 microg/mL and > or =1.0 microg/mL, respectively. In addition, 95.9%, 100.0% and 87.6% of subjects had seroprotective antibody concentrations against diphtheria, tetanus and hepatitis B, respectively. The seroprotection rate to hepatitis B increased significantly to 94.3% in subjects who received a dose of HBV at birth. The pertussis vaccine response rate was > or =95%. Seroprotection/vaccine response rates to all antigens after DTPw-HBV/Hib were at least as good as those observed after vaccination with GSK Biologicals' licensed Tritanrix HepB/Hiberix (containing 10 microg PRP) which was used as comparator. Although redness >20 mm in diameter and fever > or = 37.5 degrees C (axillary route) occurred more often after the new DTPw-HBV/Hib vaccine (p < 0.05), other Grade 3 adverse events occurred similarly between the groups. The new DTPw-HBV/Hib vaccine was as immunogenic and well tolerated as the licensed control vaccine when administered according to the immunologically challenging EPI schedule. A birth dose of HBV is important to maximize protection against hepatitis B in endemic regions where the EPI schedule is in place.