Immunogenicity and Safety of a Quadrivalent Meningococcal Conjugate Vaccine Versus Nimenrix in Healthy Adolescents: A Randomized Phase IIIb Multicenter Study.

INTRODUCTION: Many immunization programs in Europe recommend quadrivalent meningococcal vaccinations, which are often administered concomitantly with other vaccines. We compared the immune response of a tetanus toxoid conjugated quadrivalent meningococcal vaccine (MenACYW-TT, MenQuadfi®) with another quadrivalent meningococcal conjugate vaccine (MCV4-TT; Nimenrix®) when administered alone or concomitantly with Tdap-IPV and 9vHPV vaccines in adolescents. METHODS: In this phase IIIb trial, healthy adolescents (MenC-naïve or MenC-primed before 2 years of age) from Spain, Italy, Hungary, and Singapore were randomized in a 3:3:2 ratio to receive either MenACYW-TT or MCV4-TT alone, or MenACYW-TT concomitantly with 9vHPV and Tdap-IPV. The primary objective was to demonstrate the non-inferiority of the seroprotection rate (human serum bactericidal assay [hSBA] titer ≥ 1:8) to serogroups A, C, W, and Y 30 days post-vaccination with a single dose of MenACYW-TT or MCV4-TT. Secondary objectives included describing hSBA titers for the four serogroups before and 1 month following vaccination and according to MenC priming status. RESULTS: A total of 463 participants were enrolled (MenACYW-TT, n = 173; MCV4-TT, n = 173; MenACYW-TT/9vHPV/Tdap-IPV n = 117). Non-inferiority based on seroprotection was demonstrated for MenACYW-TT versus MCV4-TT for all serogroups. Immune responses were comparable whether MenACYW-TT was administered alone or concomitantly with Tdap-IPV and 9vHPV. Post-vaccination hSBA GMTs were higher in MenACYW-TT vs. MCV4-TT for serogroups C, Y, and W and comparable for serogroup A. The percentages of participants with an hSBA vaccine seroresponse were higher in MenACYW-TT vs. MCV4-TT for all serogroups. For serogroup C, higher GMTs were observed in both MenC-naïve or -primed participants vaccinated with MenACYW-TT vs. MCV4-TT. Seroprotection and seroresponse were higher in MenC-naïve participants vaccinated with MenACYW-TT vs. MCV4-TT and comparable in MenC-primed. The safety profiles were comparable between groups and no new safety concerns were identified. CONCLUSIONS: These data support the concomitant administration of MenACYW-TT with 9vHPV and Tdap-IPV vaccines in adolescents. TRIAL REGISTRATIONS: Clinicaltrials.gov, NCT04490018; EudraCT: 2020-001665-37; WHO: U1111-1249-2973.

MenACYW conjugate vaccine has been made to protect against meningococcal disease caused by four common types of bacteria (germs) called Neisseria meningitidis (or meningococcus), A, C, W, and Y. Many people, particularly adolescents, have the germs of this disease in their nose or throat, and therefore may develop the disease or transmit the bacteria to other people. Hence, adolescent meningococcal vaccination against serogroups ACWY is increasingly recommended in several countries. This study assessed the immune response to these serogroups in healthy adolescents after one dose of MenACYW conjugate vaccine or Nimenrix^®, a meningococcal licensed vaccine. Moreover, the immune response and safety were assessed when the vaccines were given alone or when given concomitantly with other adolescent vaccines, including the human papillomavirus (9vHPV) and tetanus, diphtheria, pertussis, and poliomyelitis (Tdap-IPV) vaccines. A total of 463 adolescents (aged 10­17 years) participated in this study and received either MenACYW or Nimenrix^® alone, or MenACYW concomitantly with 9vHPV and Tdap-IPV vaccine. The immune response induced by MenACYW was as good as the immune response induced by Nimenrix^®, and when given alone or concomitantly with 9vHPV and Tdap IPV vaccines. None of the participants experienced any serious side effects of any vaccine. The most common non-serious side effects were injection site pain, muscle pain, and headache. These data support the use of MenACYW in adolescents, with or without concomitant administration with 9vHPV and Tdap-IPV, which may help to increase the number of adolescents vaccinated.

Immunogenicity and safety of a tetravalent dengue vaccine and a bivalent HPV vaccine given concomitantly or sequentially in girls aged 9 to 14 years in Mexico.

Dengue is endemic in several regions, and the global incidence is increasing. The recombinant, live, attenuated, tetravalent dengue vaccine (CYD-TDV) is recommended for dengue seropositive individuals ≥ 9 years. Human papillomavirus (HPV) vaccination is recommended for girls aged 9-14 years to prevent HPV infection-related cancers. This study assessed the immunogenicity and safety of a bivalent HPV (types 16 and 18) vaccine and CYD-TDV when co-administered concomitantly or sequentially. This was a Phase IIIb, randomized, open-label, multicenter study in girls aged 9-14 years in Mexico (NCT02979535). Participants were randomized 1:1 to receive three doses of CYD-TDV 6 months apart and two doses of bivalent HPV vaccine either concomitantly with, or 1 month before (sequentially), the first 2 CYD-TDV doses. Antibody levels were measured at baseline and 28-days after each vaccine dose for all participants, using an enzyme-linked immunosorbent assay for HPV-16 and HPV-18 antibodies, and a plaque reduction neutralization test for the four dengue serotypes; results are reported only for participants who were seropositive at baseline. Safety was assessed for all randomized participants throughout the study. Of the randomized participants, 305/478 (63.8%) were seropositive for dengue at baseline: 154 in the concomitant group and 151 in the sequential group. After the last HPV vaccine dose, the antibody titers for HPV were comparable in seropositive participants between treatment groups, with between group titer ratios of 0.966 for HPV-16 and 0.999 for HPV-18. After dose 3 of CYD-TDV, antibody titers were comparable for the concomitant and sequential groups across all serotypes, with between-group ratios close to 1 (serotype 1: 0.977; serotype 2: 0.911; serotype 3: 0.921; serotype 4: 0.931). CYD-TDV and a bivalent HPV vaccine administered concomitantly or sequentially in dengue seropositive girls aged 9-14 years elicited comparable immune responses with similar safety profiles.

Immunogenicity and Safety of a Tetravalent Dengue Vaccine Administered Concomitantly or Sequentially With Tdap Vaccine: Randomized Phase IIIb Trial in Healthy Participants 9-60 Years of Age in the Philippines.

BACKGROUND: Incorporating dengue vaccination into existing childhood vaccination programs could increase vaccine coverage. This study assessed the safety and immunogenicity of concomitant versus sequential administration of the combined tetanus toxoid, reduced diphtheria toxoid and acellular pertussis (Tdap) vaccine and the tetravalent dengue vaccine (CYD-TDV). METHODS: This phase IIIb, randomized, open-label, multicenter study was conducted in the Philippines in individuals 9-≤60 years of age (NCT02992418). Participants were to receive 3 CYD-TDV doses 6 months apart, the first dose administered either concomitantly or sequentially (28 days post-Tdap). Antibody levels were measured at baseline and 28 days post-first doses of Tdap vaccine and CYD-TDV, using enzyme-linked immunosorbent assay (pertussis, tetanus), micrometabolic inhibition test-toxin neutralization assay (diphtheria) and plaque reduction neutralization test (dengue). Immunogenicity was assessed for all participants, and statistical analysis reported for baseline dengue seropositive participants. Safety was assessed throughout. RESULTS: Among 688 randomized participants, 629 (91.4%) were baseline dengue seropositive (concomitant group, n = 314 and sequential group, n = 315). After the first dose, non-inferiority of immune responses between concomitant and sequential vaccination was achieved; between-group geometric mean antibody concentration ratios were close to 1 for anti-PT, anti-FHA, anti-PRN and anti-FIM, between-group differences in percent achieving seroprotection (titers ≥0.1 IU/mL) were 0.26% (diphtheria) and 0.66% (tetanus), and between-group geometric mean antibody titer ratios were close to 1 for dengue serotypes 1-4. Safety profiles in both study groups were comparable. CONCLUSIONS: CYD-TDV and Tdap vaccine administered concomitantly or sequentially in baseline dengue seropositive participants elicited comparable immunogenicity and safety profiles.

Immunogenicity and Safety of a Tetravalent Dengue Vaccine Administered Concomitantly or Sequentially With Quadrivalent Human Papillomavirus Vaccine in Boys and Girls 9-13 Years of Age in Malaysia: A Phase IIIb, Randomized, Open-label Study.

BACKGROUND: Incorporating dengue vaccination within existing vaccination programs could help improve dengue vaccine coverage. We assessed the immunogenicity and safety of a quadrivalent human papillomavirus (HPV) vaccine administered concomitantly or sequentially with a tetravalent dengue vaccine (CYD-TDV) in healthy children 9-13 years of age in Malaysia. METHODS: In this phase IIIb, open-label, multicenter study (NCT02993757), participants were randomized 1:1 to receive 3 CYD-TDV doses 6 months apart and 2 doses of quadrivalent HPV vaccine concomitantly with, or 1 month before (sequentially), the first 2 CYD-TDV doses. Only baseline dengue-seropositive participants received the 3 doses. Antibody levels were measured at baseline and 28 days after each injection using an enzyme-linked immunosorbent assay for HPV-6, -9, -16 and -18, and the 50% plaque reduction neutralization test for the 4 dengue serotypes; immunogenicity results are presented for baseline dengue-seropositive participants. Safety was assessed throughout the study for all participants. RESULTS: At baseline, 197 of 528 (37.3%) randomized participants were dengue-seropositive [n = 109 (concomitant group) and n = 88 (sequential group)]. After the last HPV vaccine dose, antibody titers for HPV among baseline dengue-seropositive participants were similar between treatment groups, with between-group titer ratios close to 1 for HPV-6 and 0.8 for HPV-11, -16, and -18. After CYD-TDV dose 3, dengue antibody titers were similar between treatment groups for all serotypes [between-group ratios ranged from 0.783 (serotype 2) to 1.07 (serotype 4)]. No safety concerns were identified. CONCLUSIONS: The immunogenicity and safety profiles of CYD-TDV and quadrivalent HPV vaccines were unaffected when administered concomitantly or sequentially in dengue-seropositive children.

Immunogenicity and safety of a single dose of a live attenuated Japanese encephalitis chimeric virus vaccine in Vietnam: A single-arm, single-center study.

OBJECTIVE: To describe the immunogenicity and safety of the Japanese encephalitis chimeric virus vaccine (JE-CV) in children and adults in Vietnam. METHODS: In this prospective, open-label, single-center, single-arm study, 250 healthy participants aged 9 months to 60 years received a single dose of JE-CV (IMOJEV®). JE neutralizing antibody titers were assessed at baseline and 28days after vaccination using the 50% plaque reduction neutralization test (PRNT50). Safety and reactogenicity were assessed through solicited and unsolicited adverse events. FINDINGS: Seroconversion (titer ≥10 [1/dil] in participants JE seronegative [titer <10] at baseline [per protocol analysis], or a 4-fold rise from a baseline titer ≥10) and seroprotection (titer ≥10 [1/dil]) rates 28days after vaccination were both 98.5% (132/134) in the per protocol analysis, and 82.4% (201/244) and 98.8% (242/245), respectively, in the full analysis set. Geometric mean titers (GMTs) increased in all age groups from Day 0 to Day 28; Day 28/Day 0 GMT ratios were 55.3 (95% confidence interval [CI] 38.4-79.8), 348 (95% CI 211-572), 296 (95% CI 152-576) and 194 (95% CI 13.1-2870) in those aged 9 months to 4 years, 5-11 years, 12-17 years and 18-60 years, respectively, in the per protocol analysis. There were no safety concerns during the study. CONCLUSION: A single dose of JE-CV in children and adults aged 9 months to 60 years in Vietnam elicited a protective immune response and was well tolerated with no safety concerns. Registered at www.clinicaltrials.gov (NCT02492165).