Immunogenicity of a Haemophilus influenzae type b-tetanus toxoid conjugate vaccine when mixed with a diphtheria-tetanus-acellular pertussis-hepatitis B combination vaccine. A new combined DTP-HBV-Hib vaccine--strategy for incorporation of Hib vaccination into childhood immunisation programmes. A new DTPw-HB/Hib combination vaccine for primary and booster vaccination of infants in Latin America. Evaluation of the immunogenicity and reactogenicity of a DTPa-HBV-IPV Combination vaccine co-administered with a Hib conjugate vaccine either as a single injection of a hexavalent combination or as two separate injections at 3, 5 and 11 months of age. The new DTPw-HBV-Hib combination vaccine can be used at the who schedule with a monovalent dose of hepatitis B vaccine at birth. Comparison of a diphtheria and tetanus toxoids and bicomponent acellular pertussis vaccine with diphtheria and tetanus toxoids and whole-cell pertussis vaccine in infants. Immunogenicity and Reactogenicity following Primary Immunisation with a Combined DTaP-HBV Vaccine and a Haemophilus influenzae Type B Vaccine Administered by Separate or Mixed Injection. Clinical reactions and immunogenicity of the BIKEN acellular diphtheria and tetanus toxoids and pertussis vaccine in 4- through 6-year-old US children. Immunogenicity and safety of a new liquid hexavalent combined vaccine compared with separate administration of reference licensed vaccines in infants.
Combination vaccines are urgently needed to reduce the number of injections given to young children. The aim of the study was to evaluate the safety and immunogenicity of a combination vaccine that contains diphtheria and tetanus toxoids and acellular pertussis antigens (DTaP), recombinant hepatitis B surface antigen (HepB) and Haemophilus influenzae type b (Hib) polysaccharide conjugated to tetanus toxoid (PRP-T).
                Four hundred five infants were randomized equally to three groups and immunized at 2, 4 and 6 months of age with: (1) DTaP/HepB vaccine used to reconstitute lyophilized PRP-T vaccine and administered as a single injection; (2) DTaP/HepB vaccine and PRP-T vaccine administered as two separate injections; or (3) DTaP, HepB and PRP-T vaccines administered as three separate injections. Safety was closely monitored, and blood specimens were obtained to assess antibody responses to each vaccine antigen.
                All study vaccines were well-tolerated, and the rates of systemic and injection site reactions were similar between groups. After the third dose the geometric mean antibody concentrations to Hib were significantly lower in subjects in Group 1 (1.63 microg/ml) compared with subjects in Groups 2 and 3 (6.26 and 6.15 microg/ml, respectively; P < 0.0001). Subjects with antibody concentrations <1.0 microg/ml after the third dose responded well to a booster dose of Hib conjugate vaccine given at 11 to 15 months of age (41 of 44 with anti-PRP > or = 1.0 microg/ml). Differences between groups for antibody responses to the other vaccine components were not clinically significant.
                Infants given a combined DTaP/ HepB/PRP-T vaccine experienced a significantly lower antibody response to the PRP-T component than infants given PRP-T vaccine as a separate injection. However, the immune response to a booster dose of Hib conjugate vaccine indicated the presence of immunologic memory. To evaluate the immunogenicity and reactogenicity of a pentavalent vaccine prepared by extemporaneously mixing diphtheria-tetanus pertussis-hepatitis B vaccine (DTP-HBV) and lyophilised Haemophilus influenzae type B (Hib)-tetanus conjugate vaccines in the same syringe, compared with the same vaccines given as separate, concomitant administrations.
                Open, randomised comparative study.
                Durban, South Africa.
                A total of 120 healthy male and female infants were enrolled in the trial and randomised into two groups; group 1 received the combined administration (DTP-HBV-Hib), and group 2 received separate administrations of DTP-HBV and Hib vaccines. Vaccines were given as a three-dose primary vaccination course at 2, 4 and 6 months [corrected] of age.
                Antibody levels were measured using standard techniques and local and general solicited symptoms were recorded using diary cards.
                All subjects had seroprotective titres against diphtheria and tetanus; and antipolyribose-ribitol phosphate (PRP) titres > or = 0.15 microgram/ml 1 month after the final dose. A vaccine response (defined as post-vaccination titres > or = 15 ELISA (EL).U/ml in initially seronegative subjects; and as post-vaccination titres > or = pre-vaccination titres in initially seropositive subjects) against the pertussis component was seen in 83% and 85% of subjects in the groups receiving combined and separate administration. No differences were seen in any of the geometric mean titres (GMTs) between the two administrations either 2 months after the second dose or 1 month after the final dose. There was no observed increase in reactogenicity in the group receiving the mixed administration.
                The results demonstrate that combined DTP-HBV-Hib vaccine is well tolerated and immunogenic. In 1998 the World Health Organization (WHO) recommended the inclusion of Haemophilus influenza type B (Hib) conjugate vaccines in infant immunization programs, whenever in accordance with national priorities. GlaxoSmithKline Biologicals has developed a new pentavalent combined diphtheria-tetanus-whole cell pertussis-hepatitis B/Hib (DTPw-HB/Hib) vaccine containing 5 microg of polyribosylribitol phosphate (PRP), and we assessed the immunogenicity and reactogenicity of primary and booster vaccination of healthy children with this new vaccine compared with a reference regimen consisting of the licensed DTPw-HB (Tritanrix) and Hib (Hiberix) vaccines given as simultaneous concomitant injections.
                We performed a randomized, double-blind study from September 1998 to August 1999 to establish the immunogenicity and reactogenicity of primary and booster vaccination of healthy children with the new pentavalent combined DTPw-HB/Hib vaccine given as a single injection, compared with the reference regimen.
                Both vaccination regimens elicited excellent immune responses, with all subjects in both groups achieving seroprotective anti-PRP antibody concentrations of > or = 0.15 microg/mL one month after primary vaccination. The combined DTPw-HB/Hib vaccine was non-inferior to the licensed vaccines in terms of seroprotection/seropositivity/vaccine response rates for all antigen components. Persistence of antibodies against all study vaccine antigens up to the time of booster vaccination was comparable between groups, and a marked increase of all antibody concentrations was observed after the booster dose. Both vaccine regimens were similar in terms of their overall reactogenicity profiles.
                Our results indicate that the new DTPw-HB/Hib pentavalent combination vaccine provides an efficient and reliable way of implementing WHO recommendations for controlling hepatitis B and Hib infections on a worldwide basis. A combined DTPa-HBV-IPV/Hib vaccine containing diphtheria (D), tetanus (T), acellular pertussis (Pa), hepatitis B (HBV) and types 1, 2 and 3 inactivated polioviruses (IPV) extemporaneously mixed with a conjugated Haemophilus influenzae type b (Hib) vaccine (Group 1) was compared to the DTPa-HBV-IPV and Hib vaccines (Group 2) administered separately at 3, 5 and 11 months of age (n = 440). A microneutralization assay was used to detect antibodies against the 3 polio virus types (cut-off 1:8 dil), RIA for anti-HBs antibodies (cut-off 10 mIU/ml) and ELISA for antibodies against all other vaccine antigens (cut-off: 0.1 IU/ml for anti-tetanus and anti-diphtheria antibodies; 5 El.U/ml for antibodies against each of the 3 acellular pertussis antigens and 0.15 microg/ml for anti-PRP antibodies). Similar immune responses were observed in both groups 1 month after dose 2 as well as after dose 3. Six months after dose 2 however, the proportion of subjects maintaining an anti-tetanus antibody concentration > or = 0.1 IU/ml was lower in Group 2 and a slight group difference in favour of Group 1 was also observed for anti-PRP, anti-diphtheria and anti-polio type 1 antibody persistence prior to the third dose. The overall incidence of local and general solicited symptoms was similar in both groups. One subject discontinued study vaccination following an SAE considered to be related to vaccination. The DTPa-HBV-IPV/Hib combined vaccine is immunogenic and well tolerated when administered according to a 3, 5 and 11 month vaccination schedule and can therefore be considered as a feasible alternative to the separate administration of the pentavalent DTPa-HBV-IPV and the monovalent Hib vaccines. An open, randomized, clinical trial was conducted in order to assess the reactogenicity and immunogenicity of DTPw-HBV and Haemophilus influenzae type b (Hib) vaccines when given either as a mixed administration or as separate concomitant injections using the WHO schedule at 6, 10 and 14 weeks of age, following a dose of HBV at birth. There were no clinically relevant differences in the immune response to any component between the mixed and separate administrations. In fact the anti-tetanus GMTs were significantly higher (p=0.002) in mixed administration (3.9 IU/ml) compared with the separate administration (1.9 IU/ml). However although all subjects achieved anti-PRP titers > or = 0.15 microg/ml, higher anti-PRP GMTs were seen in the group receiving the separate administration. Importantly, the addition of Hib did not adversely alter the reactogenicity profile of DTPw-HBV. This report which demonstrates that this novel combination can be used in WHO recommended schedule. To compare the reactogenicity and immunogenicity of a diphtheria and tetanus toxoids and two-component acellular pertussis (ADTP) vaccine with a US-licensed whole-cell (WDTP) vaccine.
                General pediatric practice in suburban Rochester, NY.
                Prospective, double-blind, randomized study.
                One hundred ten infants were studied; 88 (80%) received ADTP and 22 (20%) received WDTP at ages 2, 4, and 6 months.
                Vaccination.
                Temperature of 38.3 degrees C or higher (P = .03) and moderate or severe injection-site pain (P = .02) occurred less frequently in infants receiving ADTP than those receiving WDTP for the combined three doses. Following the third dose, ADTP vaccination produced higher antibody responses than WDTP to pertussis toxin (geometric mean enzyme-linked immunosorbent assay IgG was 52.2 vs 12.5; P < .001) and to filamentous hemagglutinin (geometric mean IgG was 182.8 vs 3.5; P < .001). No interference in the diphtheria or tetanus antibody responses was observed in recipients of the ADTP vaccine.
                This two-component ADTP vaccine, when given as a primary infant series, produces fewer adverse effects and greater immunogenicity to the two pertussis components that it contains than US-licensed WDTP vaccine. The aim of this open, randomised, multicentre trial was to evaluate the immunogenicity and reactogenicity of the tetravalent diphtheria-tetanus-acellular pertussis-hepatitis B (DTaP-HBV) vaccine when given either as a mixed or as a separate concomitant injection with the Haemophilus influenzae type b (Hib) vaccine at 3, 5 and 11 months of age.
                Antibody against diphtheria, tetanus, pertussis (ELISA), hepatitis B (radioimmunoassay) and Hib polyribosylribitol phosphate (PRP) [radiolabeled antigen binding assay] was determined. Solicited local and systemic adverse events were evaluated on the day of each vaccination and for three subsequent days. Follow-up of unsolicited and serious adverse events was conducted for 30 days following each vaccination.
                A total of 360 subjects were enrolled in the study. After completion of the three-dose vaccination course, seroprotective antibody concentrations against diphtheria, tetanus and hepatitis B, together with a pertussis vaccine response, were seen in almost all subjects with immunogenicity results (n = 336). All subjects had post-vaccination Hib anti-PRP antibody concentrations of at least 0.15 mug/mL, and 97.0% and 99.4%, respectively, of the subjects receiving a single or separate injections had Hib anti-PRP antibody concentrations >/=1.0 mug/mL. Addition of the Hib vaccine to the tetravalent DTaP-HBV vaccine did not increase the incidence of local or systemic reactions.
                Combination of DTaP-HBV and Hib vaccines in a single injection is safe, immunogenic and well tolerated, and thus has the potential to simplify the childhood immunisation schedule in Italy. OBJECTIVE--To compare the immunogenicity and reactogenicity of a two-component acellular pertussis vaccine with a whole-cell diphtheria and tetanus toxoids and pertussis vaccine (W-DTP) when administered as a booster to children 4 through 6 years of age. DESIGN--This was a randomized, double-blind study. SETTING--Children in this study were from three general pediatric practices (two were private, one was university-affiliated). PARTICIPANTS--Three hundred and sixteen 4- through 6-year-old children who had received four previous W-DTP immunizations at the recommended times were studied. SELECTION PROCEDURES AND INTERVENTIONS--Children were randomly assigned in a 1:3 ratio to receive either W-DTP or one of three lots of acellular diphtheria and tetanus toxoids and pertussis vaccine (A-DTP). The A-DTPs contained 3.75 micrograms each of lymphocytosis promoting factor and filamentous hemagglutinin protein nitrogen per 0.5 mL and the same concentrations of diphtheria and tetanus toxoids as W-DTP. Serum samples were obtained on the day of immunization and 4 to 6 weeks later. Adverse reactions were recorded by parents at 6, 24, 48, and 72 hours. MEASUREMENTS AND RESULTS--An indirect enzyme-linked immunosorbent assay (ELISA) method determined IgG antibody response to lymphocytosis promoting factor, filamentous hemagglutinin, and tetanus toxoid; a CHO cell assay measured neutralizing antibodies to pertussis toxin; and serum neutralization on VERO cells assayed diphtheria antitoxin. One month after booster doses were administered, the geometric mean antibody levels for A-DTP vs W-DTP were IgG filamentous hemagglutinin, 362 vs 104 ELISA U/mL; IgG lymphocytosis promoting factor, 408 vs 81 ELISA U/mL; CHO cell, 210 vs 107; diphtheria, 21.7 vs 12.1 U/mL; and tetanus, 2.86 vs 2.04 Eq/mL. Following immunization with A-DTP, local and systemic adverse experiences were 30% to 50% and 20% to 30% fewer, respectively, as compared with W-DTP. CONCLUSIONS--The BIKEN A-DTP vaccine used in this study demonstrates enhanced immunogenicity to lymphocytosis promoting factor, filamentous hemagglutinin, and other measured antigens and less reactogenicity compared with licensed W-DTP [corrected]. The immunogenicity and safety of a new liquid hexavalent vaccine (diphtheria-tetanus-acellular pertussis-inactivated polio vaccine-hepatitis B-polyribosyl ribitol phosphate conjugated to tetanus protein; Hexavac; Aventis Pasteur MSD, Lyon, France) are compared with those of reference vaccines [diphtheria-tetanus-acellular pertussis-inactivated polio vaccine reconstituting lyophilized purified Haemophilus influenzae polysaccharide conjugated to tetanus protein vaccine (Pentavac; Aventis Pasteur MSD) and hepatitis B vaccine (H-B-Vax II; Aventis Pasteur MSD)] injected separately at the same visit in a prospective multicenter, comparative, open label trial.
                Infants were randomized to receive Hexavac (n = 423) or Pentavac and H-B-Vax II (n = 425) as a primary immunization series at 2, 4 and 6 months of age. Seroprotection and seroconversion rates against all antigens at 1 month after the primary series were compared between the two vaccine groups with 95% confidence intervals (CI0.95) and were considered clinically equivalent (not inferior) when the upper limit of the 95% confidence interval on the difference (reference, hexavalent) was below predefined differences.
                Hexavac met and surpassed the pre-defined criteria for clinical equivalence to Pentavac and H-B-Vax II given concomitantly. It elicited similar seroprotection and seroconversion rates against all antigens. Seroprotection and seroconversion rates obtained 1 month after the third dose of Hexavac were >90% for all antigens. The postimmunization antibody geometric mean titers (GMT) for hepatitis B and purified Haemophilus influenzae polysaccharide were about 2-fold higher in infants who received the reference vaccines than in infants who had received Hexavac. GMTs for poliovirus antibodies tended to be enhanced in infants vaccinated with Hexavac. GMTs for all other antigens were very similar among both groups. Hexavac was generally well-tolerated. At least one local reaction was reported in 20.3% of Hexavac injections compared with 15.8% at the Pentavac injections site and 3.8% at the H-B-Vax II injections site. These reactions were generally mild and transient. At least one systemic adverse event was reported in 45.7% of Hexavac injections compared with 42.2% of Pentavac and H-B-Vax II injections (mild fever, irritability and drowsiness were most frequently reported). The frequency of adverse events was not significantly different between groups. No vaccine-related serious adverse event occurred during the study.
                This liquid hexavalent vaccine was generally well-tolerated and provided immune responses adequate to be protective against six infectious diseases with a single injection, given at 2, 4 and 6 months of age.
We could not conclude that the immune responses elicited by the combined vaccine were different from or equivalent to the separate vaccines. There was significantly less immunological response for HIB and tetanus and more local reactions in the combined injections. However, these differences rely mostly on one study each. Studies did not use an intention-to-treat (ITT) analysis and we were uncertain about the risk of bias in many of the studies. These results are therefore inconclusive. Studies addressing clinical end points whenever possible, using correct methodology and a large enough sample size should be conducted.