Prevention of vaccine-matched and mismatched influenza in children aged 6–35 months: a multinational randomised trial across five influenza seasons

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F62690094%3A18810%2F18%3A50015124" target="_blank" >RIV/62690094:18810/18:50015124 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1016/S2352-4642(18)30062-2" target="_blank" >http://dx.doi.org/10.1016/S2352-4642(18)30062-2</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/S2352-4642(18)30062-2" target="_blank" >10.1016/S2352-4642(18)30062-2</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Prevention of vaccine-matched and mismatched influenza in children aged 6–35 months: a multinational randomised trial across five influenza seasons

Popis výsledku v původním jazyce

Background: Despite the importance of vaccinating children younger than 5 years, few studies evaluating vaccine prevention of influenza have been reported in this age group. We evaluated efficacy of an inactivated quadrivalent influenza vaccine (IIV4) in children aged 6–35 months. Methods: In this phase 3, observer-blinded, multinational trial, healthy children from 13 countries in Europe, Central America, and Asia were recruited in five independent cohorts, each in a different influenza season. Participants were randomly assigned (1:1) to either IIV4 (15 μg haemagglutinin antigen per strain per 0·5 mL dose; a single dose on day 0 for vaccine-primed children, and two doses, on days 0 and 28, for vaccine-unprimed children) or to one or two doses of a non-influenza control vaccine. Primary endpoints were moderate-to-severe influenza or all influenza (irrespective of disease severity) confirmed by RT-PCR on nasal swabs. Cultured isolates were further characterised as antigenically matched or mismatched to vaccine strains. Efficacy was assessed in the per-protocol cohort and total vaccinated cohort (time-to-event analysis), and safety was assessed in the total vaccinated cohort. Findings: Between Oct 1, 2011, and Dec 31, 2014, 12 018 children were recruited into the total vaccinated cohort (6006 children in the IIV4 group and 6012 children in the control group). 356 (6%) children in the IIV4 group and 693 (12%) children in the control group had at least one case of RT-PCR-confirmed influenza. Of these 1049 influenza strains, 138 (13%) were A/H1N1, 529 (50%) were A/H3N2, 69 (7%) were B/Victoria, and 316 (30%) were B/Yamagata. Overall, 539 (64%) of 848 antigenically characterised isolates were vaccine-mismatched (16 [15%] of 105 for A/H1N1; 368 [97%] of 378 for A/H3N2; 54 [86%] of 63 for B/Victoria; 101 [33%] of 302 for B/Yamagata). Vaccine efficacy was 63% (97·5% CI 52–72) against moderate-to-severe influenza and 50% (42–57) against all influenza in the per-protocol cohort, and 64% (53–73) against moderate-to-severe influenza and 50% (42–57) against all influenza in the total vaccinated cohort. There were no clinically meaningful safety differences between IIV4 and control. Interpretation: IIV4 prevented influenza A and B in children aged 6–35 months despite high levels of vaccine mismatch. Vaccine efficacy was highest against moderate-to-severe disease, which is the most clinically important endpoint associated with greatest burden.

Název v anglickém jazyce

Prevention of vaccine-matched and mismatched influenza in children aged 6–35 months: a multinational randomised trial across five influenza seasons

Popis výsledku anglicky

Background: Despite the importance of vaccinating children younger than 5 years, few studies evaluating vaccine prevention of influenza have been reported in this age group. We evaluated efficacy of an inactivated quadrivalent influenza vaccine (IIV4) in children aged 6–35 months. Methods: In this phase 3, observer-blinded, multinational trial, healthy children from 13 countries in Europe, Central America, and Asia were recruited in five independent cohorts, each in a different influenza season. Participants were randomly assigned (1:1) to either IIV4 (15 μg haemagglutinin antigen per strain per 0·5 mL dose; a single dose on day 0 for vaccine-primed children, and two doses, on days 0 and 28, for vaccine-unprimed children) or to one or two doses of a non-influenza control vaccine. Primary endpoints were moderate-to-severe influenza or all influenza (irrespective of disease severity) confirmed by RT-PCR on nasal swabs. Cultured isolates were further characterised as antigenically matched or mismatched to vaccine strains. Efficacy was assessed in the per-protocol cohort and total vaccinated cohort (time-to-event analysis), and safety was assessed in the total vaccinated cohort. Findings: Between Oct 1, 2011, and Dec 31, 2014, 12 018 children were recruited into the total vaccinated cohort (6006 children in the IIV4 group and 6012 children in the control group). 356 (6%) children in the IIV4 group and 693 (12%) children in the control group had at least one case of RT-PCR-confirmed influenza. Of these 1049 influenza strains, 138 (13%) were A/H1N1, 529 (50%) were A/H3N2, 69 (7%) were B/Victoria, and 316 (30%) were B/Yamagata. Overall, 539 (64%) of 848 antigenically characterised isolates were vaccine-mismatched (16 [15%] of 105 for A/H1N1; 368 [97%] of 378 for A/H3N2; 54 [86%] of 63 for B/Victoria; 101 [33%] of 302 for B/Yamagata). Vaccine efficacy was 63% (97·5% CI 52–72) against moderate-to-severe influenza and 50% (42–57) against all influenza in the per-protocol cohort, and 64% (53–73) against moderate-to-severe influenza and 50% (42–57) against all influenza in the total vaccinated cohort. There were no clinically meaningful safety differences between IIV4 and control. Interpretation: IIV4 prevented influenza A and B in children aged 6–35 months despite high levels of vaccine mismatch. Vaccine efficacy was highest against moderate-to-severe disease, which is the most clinically important endpoint associated with greatest burden.

Druh

J_SC - Článek v periodiku v databázi SCOPUS

CEP obor

—

OECD FORD obor

30209 - Paediatrics

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

The Lancet Child and Adolescent Health

ISSN

2352-4642

e-ISSN

—

Svazek periodika

2

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

12

Strana od-do

338-349

Kód UT WoS článku

000434768900016

EID výsledku v databázi Scopus

2-s2.0-85045202685