Immunogenicity and Safety of a Hexavalent DTwP-IPV-HB-PRP~T Vaccine Versus Separate DTwP-HB-PRP~T, bOPV, and IPV Vaccines Administered at 2, 4, 6 Months of Age Concomitantly With Rotavirus and Pneumococcal Conjugate Vaccines in Healthy Infants in Thailand.

BACKGROUND: This study investigated the immunogenicity and safety of a fully liquid, hexavalent, diphtheria (D)-tetanus (T)-whole-cell pertussis (wP)-inactivated poliovirus (IPV)-hepatitis B (HB)- Haemophilus influenzae b (PRP-T) vaccine compared to licensed DTwP-HB-PRP~T, IPV, and bivalent oral poliovirus (bOPV) vaccines following co-administration with other pediatric vaccines [pneumococcal conjugate vaccine (PCV13) and rotavirus vaccine]. METHODS: Phase III, randomized, open-label study in Thailand. Healthy infants received DTwP-IPV-HB-PRP~T at 2, 4 and 6 months of age (N = 228), or DTwP-HB-PRP~T and bOPV (2, 4 and 6 months of age) and IPV (4 months of age) (N = 231). All participants received PCV13 (2, 4 and 6 months of age) and rotavirus vaccine (2 and 4 months of age). Immunogenicity for all antigens was assessed using validated assays, and noninferiority post-third dose was evaluated for anti-D, anti-T, anti-pertussis [anti-pertussis toxin (anti-PT) and anti-fimbriae 2/3 (anti-FIM)], anti-polio 1, 2, 3, anti-HB, and anti-PRP~T. Safety was assessed using parental reports. RESULTS: Noninferiority was demonstrated for each antigen, and overall noninferiority of DTwP-IPV-HB-PRP~T versus DTwP-HB-PRP~T+bOPV+IPV was concluded. Similarity in each group was observed for the GMC ratio for antirotavirus antibodies (20.9 and 17.3, respectively) and anti-PCV13 antibodies (range: 8.46-32.6 and 7.53-33.1, respectively). Two serious adverse events were related to DTwP-IPV-HB-PRP~T (febrile convulsion and acute febrile illness) and 1 was related to DTwP-HB-PRP~T+bOPV+IPV (febrile seizure), but overall there were no safety concerns with similar rates of participants experiencing solicited (99.1% and 98.3%) and unsolicited (19.3% and 19.5%) adverse events in each group. CONCLUSIONS: This study confirmed the suitability of DTwP-IPV-HB-PRP~T primary series vaccination in combination with rotavirus and PCV13 vaccines.

Antibody Persistence Following Administration of a Hexavalent DTwP-IPV-HB-PRP~T Vaccine Versus Separate DTwP-HB-PRP~T and IPV Vaccines and Safety and Immunogenicity of a Booster Dose of DTwP-IPV-HB-PRP~T Administered With an MMR Vaccine in Healthy Infants in India.

BACKGROUND: Antibody persistence of a whole-cell pertussis-containing hexavalent vaccine (DTwP-IPV-HB-PRP~T) and its co- or sequential administration with measles, mumps, rubella (MMR) vaccine were evaluated. METHODS: Phase III, open-label, randomized, multicenter study in India. Healthy toddlers 12-24 months of age who had received DTwP-IPV-HB-PRP~T or separate DTwP-HB-PRP~T+IPV primary vaccination at 6-8, 10-12 and 14-16 weeks of age received a DTwP-IPV-HB-PRP~T booster concomitantly with MMR (N = 336) or 28 days before MMR (N = 340). Participants had received a first dose of measles vaccine. Immunogenicity assessment used validated assays and safety was by parental reports. All analyses were descriptive. RESULTS: All participants had prebooster anti-T ≥0.01 IU/mL and anti-polio 1 and 3 ≥8 1/dil, and ≥96.5% had anti-D ≥0.01 IU/mL, anti-HBs ≥10 mIU/mL, anti-polio 2 ≥8 1/dil and anti-PRP ≥0.15 µg/mL; for pertussis, antibody persistence was similar in each group. Postbooster immunogenicity for DTwP-IPV-HB-PRP~T was similar for each antigen in each group: ≥99.5% of participants had anti-D ≥0.01 IU/mL, anti-T ≥0.01 IU/mL, anti-polio 1, 2 and 3 >8 1/dil, anti-HBs ≥10 mIU/mL and anti-PRP ≥1 µg/mL; for pertussis, vaccine response was similar in each group [72.0%-75.9% (anti-PT), 80.8%-81.4% (anti-FIM), 77.6%-79.5% (anti-PRN), 78.2%-80.8% (anti-FHA)]. There was no difference in MMR immunogenicity between groups, and no difference in DTwP-IPV-HB-PRP~T booster immunogenicity based on the primary series. There were no safety concerns. CONCLUSIONS: DTwP-IPV-HB-PRP~T antibody persistence was similar to licensed comparators. Booster immunogenicity was robust after DTwP-IPV-HB-PRP~T with or without MMR, and MMR immunogenicity was not affected by coadministration with DTwP-IPV-HB-PRP~T. CLINICAL TRIALS REGISTRY INDIA NUMBER: CTRI/2020/04/024843.

A New Electrochemiluminescence-Based Multiplex Assay for the Assessment of Human Antibody Responses to Bordetella pertussis Vaccines.

INTRODUCTION: Commercially available enzyme-linked immunosorbent assay (ELISA) kits designed for pertussis diagnostic purposes are frequently used to assess antibody responses to pertussis vaccines in clinical trials, but have limited accuracy and are not calibrated against international standards. We developed a new electrochemiluminescence (ECL)-based multiplexed assay and compared its performance to two commercial Bordetella pertussis ELISA kits and to historical in-house ELISAs. METHODS: The ECL assay quantifies serum concentrations of antibodies against four B. pertussis antigens: pertussis toxin (PT), filamentous hemagglutinin (FHA), pertactin (PRN), and fimbrial agglutinogen (FIM). The assay was validated for precision, accuracy, dilutability, lower limit of quantification, and specificity. Sera from a clinical trial (CTRI/2016/11/007434) were used to compare the ECL assay to two commercial ELISA kits available from GenWay BioTech and Demeditec Diagnostics for accuracy, linearity, specificity, and concordance to both internal (WWO-2-043) and international (NIBSC 06/140) references. Sera from four clinical trials (NCT02587520, NCT00255047, NCT00347958, NCT01346293) were used to compare the concordance to clinical ELISAs. Informed consent was ensured prior to using any sera. RESULTS: Precision, accuracy, dilutability, lower limit of quantification, and specificity were demonstrated for the ECL assay. Concordance between the ECL assay and established clinical ELISAs was met for antibody responses to PT, FIM, and PRN, but not for FHA. The ECL assay demonstrated higher accuracy and linearity than the ELISA kits. While concordance between the ECL and commercial kits was low, the ECL assay better distinguished between pre- and post-vaccination clinical samples. CONCLUSION: The new ECL assay was validated for the quantitative evaluation of anti-PT, anti-FHA, anti-FIM, and anti-PRN IgG antibodies in samples from clinical trials, and demonstrated equivalent or better performance than two commercially available ELISA kits.

Effect of prophylactic or therapeutic administration of paracetamol on immune response to DTwP-HepB-Hib combination vaccine in Indian infants.

BACKGROUND: Vaccination is considered as the most cost effective method for preventing infectious diseases. Low grade fever is a known adverse effect of vaccination. In India, it is a common clinical practice to prescribe paracetamol either prophylactically or therapeutically to manage fever. Some studies have shown that paracetamol interferes with antibody responses following immunization. This manuscript reports the outcome of a post hoc analysis of data from a clinical trial of a pentavalent vaccine in Indian infants where paracetamol was not used or was used either as prophylaxis or for treatment of fever. METHODS: Pre and post vaccine antibody levels against Diphtheria, Tetanus, Pertussis, Hepatitis B, Haemophilus influenzae type B were assessed in no paracetamol and paracetamol groups. The paracetamol group was further divided into prophylactic and treatment groups. RESULTS: Similar rates of seroprotection/seroresponse for anti-D, anti-T, anti-wP, anti-PT, anti-HBs and anti-PRP were observed in all the groups. There was no clear tendency for difference in percentage seroprotection/seroresponse and geometric mean (GM) titers in any of the groups. CONCLUSION: The study found no evidence that paracetamol usage either as prophylactic or for treatment impact immunological responses to DTwP-HepB-Hib combination vaccine. [Clinical trial registry of India (study registration number CTRI/2012/08/002872)].