DTaP vaccine(Wyeth AB)

This study explores attitudes toward diphtheria-tetanus-acellular pertussis (DTaP), measles-mumps-rubella (MMR), influenza, and coronavirus disease 2019 (COVID-19) vaccines among English-speaking and Spanish-speaking parents of infants in a safety-net setting. Parents aged 18 years or older were recruited from outpatient clinics between December 2020 and December 2021. The interviews were then recorded, transcribed, translated, and qualitatively analyzed using the modified grounded theory. Thirty-two individuals participated (18 English-speaking and 14 Spanish-speaking). Almost all supported receiving routine childhood vaccines, DTaP, influenza, and MMR and believed that vaccines promote health. Vaccine concerns differed by each vaccine. Few participants expressed concerns about DTaP and MMR vaccines. Concerns around influenza vaccines often stemmed from personal experience and perceived increased risk of flu-like illnesses. Participants expressed the most concerns related to COVID-19 vaccinations, including age-based immunity of their infants. Based on these findings, future interventions to improve vaccine uptake may focus on benefits common to all vaccines, while addressing vaccine-specific concerns.

This phase 1 trial assessed the safety and immunogenicity of an investigational tetanus/diphtheria/acellular pertussis vaccine combined with CpG 1018 adjuvant 1500 μg (Tdap-1018 1500 μg) or 3000 μg (Tdap-1018 3000 μg) in adults and adolescents. In this randomized, active-controlled, multicenter, dose-escalation trial, healthy participants aged 10 to 22 years received 1 dose of Tdap-1018 1500 μg, Tdap-1018 3000 μg, or Boostrix. Geometric mean concentrations (GMCs) and booster response rates (BRRs) for antibodies against pertussis (pertussis toxin, filamentous hemagglutinin, pertactin), tetanus, and diphtheria antigens, and neutralizing antibodies against pertussis toxin were assessed 4 weeks after vaccination. Safety and tolerability were assessed for solicited post-injection reactions within 7 days after vaccination and unsolicited adverse events up to 12 weeks after vaccination. Of 117 enrolled participants, 80 adults (92%) and 30 adolescents (100%) completed the study. Both Tdap-1018 formulations were generally well tolerated, with no vaccine-related serious adverse events. Frequency and severity in post-injection reactions after Tdap-1018 administration were similar to Boostrix except for higher proportions of moderate pain for Tdap-1018. In adults at week 4, ratio of GMCs and BRRs for all antigens in the 3000-μg group were similar to or higher than Boostrix, with significantly higher GMC ratios for anti-pertussis toxin (2.1 [1.5-3.0]) and anti-tetanus (1.8 [1.1-2.9]) and significantly higher BRRs for anti-pertussis toxin (difference [95% CI]: 34.5% [13.4-54.6]), anti-pertactin (19.2% [4.4-38.1]), and anti-tetanus (30.0% [3.6-52.7]) antibodies. For adolescents, in the 3000-μg group, ratio of GMCs and BRRs were similar to or higher than Boostrix for all antigens. Both Tdap-1018 formulations showed acceptable safety and tolerability profiles. Tdap-1018 3000 μg induced similar or higher immune responses than Boostrix. ACTRN12620001177943 (Australian New Zealand Clinical Trials Registry; https://anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=ACTRN12620001177943p).