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 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 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 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).