BACKGROUND: Transplacentally transferred antibodies induced by maternal pertussis vaccination interfere with infant immune responses to pertussis primary vaccination. We evaluated whether this interference remains in toddlers after booster vaccination. METHODS: In a prior phase IV, observer-blind, placebo-controlled, randomized study (NCT02377349), pregnant women in Australia, Canada and Europe received intramuscular tetanus-reduced-antigen-content diphtheria-three-component acellular pertussis vaccine (Tdap group) or placebo (control group) at 270/7-366/7 weeks' gestation, with crossover immunization postpartum. Their infants were primed (study NCT02422264) and boosted (at 11-18 months; current study NCT02853929) with diphtheria-tetanus-three-component acellular pertussis-hepatitis B virus-inactivated poliovirus/Haemophilus influenzae type b vaccine (DTaP-HepB-IPV/Hib) and 13-valent pneumococcal conjugate vaccine. Immunogenicity before and after booster vaccination, and reactogenicity and safety of the booster were evaluated descriptively. RESULTS: 263 (Tdap group) and 277 (control group) toddlers received a DTaP-HepB-IPV/Hib booster. Pre-booster vaccination, observed geometric mean concentrations (GMCs) for the three pertussis antigens and diphtheria were 1.4-1.5-fold higher in controls than in the Tdap group. No differences were observed for the other DTaP-HepB-IPV/Hib antigens. One month post-booster vaccination, booster response rates for pertussis antigens were ≥ 92.1% and seroprotection rates for the other DTaP-HepB-IPV/Hib antigens were ≥ 99.2% in both groups (primary objective). Higher post-booster GMCs were observed in controls versus the Tdap group for anti-filamentous hemagglutinin (1.2-fold), anti-pertussis toxoid (1.5-fold) and anti-diphtheria (1.4-fold). GMCs for the other DTaP-HepB-IPV/Hib antigens were similar between groups. Serious adverse events were reported for three toddlers (controls, not vaccination-related). One death occurred pre-booster (Tdap group, not vaccination-related). CONCLUSIONS: As a consequence of interference of maternal pertussis antibodies with infant immune responses to pertussis primary vaccination, pertussis antibody concentrations were still lower in toddlers from Tdap-vaccinated mothers before DTaP-HepB-IPV/Hib booster vaccination. After the booster, antibody concentrations were lower for filamentous hemagglutinin and pertussis toxoid but not for pertactin. The clinical significance of this interference requires further evaluation. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT02853929.

• Klíčová slova
• Blunting, Booster, Maternal immunization, Pertussis, Tdap vaccine, Toddlers,
• MeSH
• difterie * prevence a kontrola   MeSH
• hemofilové vakcíny * MeSH
• imunita MeSH
• kojenec MeSH
• kombinované vakcíny MeSH
• lidé MeSH
• následné studie MeSH
• pertuse * prevence a kontrola   MeSH
• poliovirová vakcína inaktivovaná MeSH
• předškolní dítě MeSH
• protilátky bakteriální MeSH
• sekundární imunizace MeSH
• těhotenství MeSH
• tetanus * prevence a kontrola   MeSH
• vakcína proti diftérii, tetanu a pertusi MeSH
• vakcína proti záškrtu, tetanu a černému kašli * MeSH
• vakcinace MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• předškolní dítě MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH
• Geografické názvy
• Austrálie MeSH
• Evropa MeSH
• Kanada MeSH
• Názvy látek
• hemofilové vakcíny * MeSH
• kombinované vakcíny MeSH
• poliovirová vakcína inaktivovaná MeSH
• protilátky bakteriální MeSH
• vakcína proti diftérii, tetanu a pertusi MeSH
• vakcína proti záškrtu, tetanu a černému kašli * MeSH

BACKGROUND: Pertussis immunization during pregnancy is recommended in many countries. Data from large randomized controlled trials are needed to assess the immunogenicity, reactogenicity and safety of this approach. METHODS: This phase IV, observer-blind, randomized, placebo-controlled, multicenter trial assessed immunogenicity, transplacental transfer of maternal pertussis antibodies, reactogenicity and safety of a reduced-antigen-content diphtheria-tetanus-three-component acellular pertussis vaccine (Tdap) during pregnancy. Women received Tdap or placebo at 27-36 weeks' gestation with crossover ≤ 72-hour-postpartum immunization. Immune responses were assessed before the pregnancy dose and 1 month after, and from the umbilical cord at delivery. Superiority (primary objective) was reached if the lower limits of the 95% confidence intervals (CIs) of the pertussis geometric mean concentration (GMC) ratios (Tdap/control) in cord blood were ≥ 1.5. Solicited and unsolicited adverse events (AEs) and pregnancy-/neonate-related AEs of interest were recorded. RESULTS: 687 pregnant women were vaccinated (Tdap: N = 341 control: N = 346). Superiority of the pertussis immune response (maternally transferred pertussis antibodies in cord blood) was demonstrated by the GMC ratios (Tdap/control): 16.1 (95% CI: 13.5-19.2) for anti-filamentous hemagglutinin, 20.7 (15.9-26.9) for anti-pertactin and 8.5 (7.0-10.2) for anti-pertussis toxoid. Rates of pregnancy-/neonate-related AEs of interest, solicited general and unsolicited AEs were similar between groups. None of the serious AEs reported throughout the study were considered related to maternal Tdap vaccination. CONCLUSIONS: Tdap vaccination during pregnancy resulted in high levels of pertussis antibodies in cord blood, was well tolerated and had an acceptable safety profile. This supports the recommendation of Tdap vaccination during pregnancy to prevent early-infant pertussis disease. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT02377349.

• Klíčová slova
• Adult formulation acellular pertussis vaccine, Maternal immunization, Tdap,
• MeSH
• imunita získaná od matky * MeSH
• jednoduchá slepá metoda MeSH
• lidé MeSH
• matka - expozice noxám * MeSH
• novorozenec MeSH
• pertuse * prevence a kontrola   MeSH
• protilátky bakteriální krev   MeSH
• těhotenství MeSH
• vakcína proti záškrtu, tetanu a černému kašli aplikace a dávkování   škodlivé účinky   MeSH
• vakcinace MeSH
• Check Tag
• lidé MeSH
• novorozenec MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky, fáze IV MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH
• Názvy látek
• protilátky bakteriální MeSH
• vakcína proti záškrtu, tetanu a černému kašli MeSH

BACKGROUND: Pertussis immunization during pregnancy results in high pertussis antibody concentrations in young infants but may interfere with infant immune responses to post-natal immunization. METHODS: This phase IV, multi-country, open-label study assessed the immunogenicity and safety of infant primary vaccination with DTaP-HepB-IPV/Hib and 13-valent pneumococcal conjugate vaccine (PCV13). Enrolled infants (6-14 weeks old) were born to mothers who were randomized to receive reduced-antigen-content diphtheria-tetanus-three-component acellular pertussis vaccine (Tdap group) or placebo (control group) during pregnancy (270/7-366/7 weeks' gestation) with crossover immunization postpartum. All infants received 2 or 3 DTaP-HepB-IPV/Hib and PCV13 doses according to national schedules. Immunogenicity was assessed in infants pre- and 1 month post-primary vaccination. The primary objective was to assess seroprotection/vaccine response rates for DTaP-HepB-IPV/Hib antigens 1 month post-primary vaccination. RESULTS: 601 infants (Tdap group: 296; control group: 305) were vaccinated. One month post-priming, seroprotection rates were 100% (diphtheria; tetanus), ≥98.5% (hepatitis B), ≥95.9% (polio) and ≥94.5% (Hib) in both groups. Vaccine response rates for pertussis antigens were significantly lower in infants whose mothers received pregnancy Tdap (37.5-77.1%) versus placebo (90.0-99.2%). Solicited and unsolicited adverse event rates were similar between groups. Serious adverse events occurred in 2.4% (Tdap group) and 5.6% (control group) of infants, none were vaccination-related. CONCLUSIONS: Pertussis antibodies transferred during pregnancy may decrease the risk of pertussis infection in the first months of life but interfere with the infant's ability to produce pertussis antibodies, the clinical significance of which remains unknown. Safety and reactogenicity results were consistent with previous experience. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT02422264.

• Klíčová slova
• Blunting, Infants, Maternal immunization, Pertussis, Tdap vaccine,
• MeSH
• hemofilové vakcíny imunologie   MeSH
• kojenec MeSH
• kombinované vakcíny imunologie   MeSH
• lidé MeSH
• následné studie MeSH
• pneumokokové vakcíny imunologie   MeSH
• poliovirová vakcína inaktivovaná imunologie   MeSH
• protilátky bakteriální krev   MeSH
• těhotenství MeSH
• vakcína proti diftérii, tetanu a pertusi imunologie   MeSH
• vakcína proti hepatitidě B imunologie   MeSH
• vakcína proti záškrtu, tetanu a černému kašli aplikace a dávkování   MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky, fáze IV MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH
• Názvy látek
• 13-valent pneumococcal vaccine MeSH Prohlížeč
• diphtheria-tetanus-acellular pertussis-inactivated poliovirus-Haemophilus influenzae b conjugate-hepatitis B vaccine MeSH Prohlížeč
• hemofilové vakcíny MeSH
• kombinované vakcíny MeSH
• pneumokokové vakcíny MeSH
• poliovirová vakcína inaktivovaná MeSH
• protilátky bakteriální MeSH
• vakcína proti diftérii, tetanu a pertusi MeSH
• vakcína proti hepatitidě B MeSH
• vakcína proti záškrtu, tetanu a černému kašli MeSH