[Immunogenicity and safety of DTaP-IPV//PRP-T combined vaccine in infants in China].

OBJECTIVE: The aim of this study was to demonstrate the immunogenicity and safety of diphtheria, tetanus, pertussis (acellular, component), poliomyelitis (inactivated) vaccine (adsorbed) and Haemophilus influenzae type b conjugate vaccine (DTaP-IPV//PRP-T) combined vaccine compared with commercially available DTaP (diphtheria, tetanus and pertussis), Haemophilus influenzae type b (Hib), tetanus conjugate and IPV monovalent vaccine. METHODS: Subjects were randomly divided into three groups, Group A and Group B were DTaP-IPV//PRP-T combined vaccine (PENTAXIM(TM)) vaccinated at 2, 3, 4 months of age or 3, 4, 5 months of age respectively; Group C was commercially available DTaP. Hib tetanus conjugate (Act-HIB(TM)) and IPV (IMOVAX PolioTM(TM)) vaccines vaccinated at 3, 4, 5 months of age. All groups received booster dose at 18 to 20 months of age, with antibody titers tested. Non-inferiority analysis was demonstrated in terms of seroprotection/seroconversion rates between Group A, Group B respectively and Group C. Safety information was collected after each vaccination to assess the safety of investigational vaccines. RESULTS: The non-inferiority of DTaP-IPV//PRP-T combined vaccine vaccinated at 2, 3, 4 or 3, 4, 5 months of age versus DTaP, Hib tetanus conjugate and IPV vaccine was demonstrated for all vaccine antigens in both primary and booster phases in terms of seroprotection/seroconversion rates. DTaP-IPV//PRP-T combined vaccine was well tolerated. The rate of solicited/unsolicited severe adverse reactions was very low and similar to the control vaccines. CONCLUSION: DTaP-IPV//PRP-T combined vaccine was highly immunogenic with good safety profile in Chinese infants, which was comparable to the commercially available control vaccines.

Antibody persistence at 18-20 months of age and safety and immunogenicity of a booster dose of a combined DTaP-IPV//PRP∼T vaccine compared to separate vaccines (DTaP, PRP∼T and IPV) following primary vaccination of healthy infants in the People's Republic of China.

This study assessed the antibody persistence, and the immunogenicity and safety of a booster dose of a DTaP-IPV//PRP∼T (Pentaxim®, Sanofi Pasteur's AcXim family) combined vaccine and of standalone vaccines one year after primary vaccination in the People's Republic of China. Participants (N=719) previously primed with DTaP-IPV//PRP∼T at 2, 3, 4 months (Group A, N=255), 3, 4, 5 months (Group B, N=233), or DTaP (Wuhan Institute of Biological Products), PRP-T (Act-Hib®) and IPV (Imovax® Polio) at 3, 4, 5 months (Group C, N=231) received boosters of the same vaccines at 18-20 months of age. Seroprotection (SP) and seroconversion (SC) were determined before and 1 month after the booster. Safety was monitored from parental reports. In all groups 87.6-100% of participants had pre-booster protective anti-PRP, -diphtheria, -tetanus and -poliovirus antibody titers; post-booster, all SP rates were 100% and SC was ≥ 80.4% for anti-pertussis titers ≥ 4-fold increase. Reactogenicity was low for each group. These data support the use of the DTaP-IPV//PRP∼T vaccine in the People's Republic of China compared to separate DTaP, IPV, and PRP∼T administration in terms of both safety and immunogenicity.

Immunogenicity and safety of a pentavalent acellular pertussis combined vaccine including diphtheria, tetanus, inactivated poliovirus and conjugated Haemophilus Influenzae type b polysaccharide for primary vaccination at 2, 3, 4 or 3, 4, 5 months of age in infants in China.

The aim was to demonstrate the immunogenicity and safety of a DTaP-IPV//PRP-T combined vaccine (Pentaxim(®)) compared to individual vaccines in infants in the People's Republic of China. Infants (N=792) were randomly assigned to receive DTaP-IPV//PRP-T at 2, 3 and 4 months of age (Group A) or 3, 4 and 5 months of age (Group B), or DTaP (Wuhan Institute of Biological Products), PRP-T (Act-Hib(®)) and IPV (Imovax(®) Polio) at 3, 4 and 5 months of age (Group C). Antibody titers were measured pre- and 1 month after the third vaccination; non-inferiority analyses were performed for seroprotection/seroconversion (SP/SC) rates. Safety was assessed 1 month after the primary series. SP/SC rates for the DTaP-IPV//PRP-T vaccine were high and non-inferior to the controls. Reactogenicity was low for each group and no hypotonic hyporesponsive episode or seizure was reported. In conclusion, the DTaP-IPV//PRP-T vaccine was highly immunogenic, non-inferior to the commercially available control vaccines and had a good safety profile for both primary administration schedules.

[Study on the safety and immunogenicity of group A + C meningococcal polysaccharide vaccine].

OBJECTIVE: In order to evaluate the safety and immunogenicity of group A + C meningococcal polysaccharide vaccine, a controlled field trial was performed among children at 6-24 months and 5-13 years old in Longsheng county, Guangxi Zhuang Autonomous Region. METHODS: More than 600 children were selected in this trial. 428 children, aged 6-24 month-old and 5-13 year-old were involved in two experimental groups and were inoculated 100 microg of group A + C meningococcal polysaccharide vaccine. 103 children in positive control group were inoculated 50 microg of group A meningococcal polysaccharide vaccine while 94 children in negative control group were inoculated 30 microg of Typhoid Vi polysaccharide vaccine. Both systemic and local reactions were observed in each group at 6 h,24 h,48 h and 72 h after inoculation. Blood samples were collected in all children before and at 1 month after inoculation. Additionally, at least 50 blood samples were taken in each experimental group at 6 and 12 months after inoculation. Serum bactericidal antibody was tested by micro bactericidal test. RESULTS: Both systemic and local reactions were mild in two experimental groups with only 3 children (0.7%) had > or = 37. 6 degrees C fever, 4 children (0.9%) appeared mild areola but all adverse reaction disappeared within 48 hours. In 5-13 year-old experimental group, the rates for four-fold increase of bactericidal antibody were 96.59% and 92.15% to group A and group C meningococcus respectively at 1 month after inoculation, and remained 90.91% and 90.08% at 12 months after inoculation. CONCLUSION: Group A + C meningococal polysaccharide vaccine was safe and having good immunogenicity among Chinese children.