tetano
Editor, Senior Moderator
J Pediatric Infect Dis Soc. 2015 Jul 16. pii: piv041. [Epub ahead of print]
[h=1]Immunogenicity and Safety of an Inactivated Quadrivalent Influenza Vaccine in US Children 6-35 Months of Age During 2013-2014: Results From A Phase II Randomized Trial.[/h] Wang L[SUP]1[/SUP], Chandrasekaran V[SUP]2[/SUP], Domachowske JB[SUP]3[/SUP], Li P[SUP]2[/SUP], Innis BL[SUP]1[/SUP], Jain VK[SUP]1[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Viruses from 2 influenza B lineages co-circulate, leading to suboptimal protection with trivalent influenza vaccines (TIV). Quadrivalent influenza vaccines (QIV) containing both lineages offer broader protection.
[h=4]METHODS:[/h] We compared inactivated seasonal QIV versus TIV (15 and 7.5 μg hemagglutinin [HA] for each influenza strain, respectively) in a phase II randomized (1 : 1), observer-blind trial in US children 6-35 months of age (identifier NCT01974895). The primary objective was to evaluate immune responses induced by QIV for the 4 vaccine strains 28 days after completion of vaccination. A secondary objective was to demonstrate superiority of QIV versus TIV for the B/Victoria strain contained in QIV but not TIV. Immunogenicity was evaluated in the per-protocol cohort (N = 280), and safety was evaluated in the intent-to-treat cohort (N = 314).
[h=4]RESULTS:[/h] Seroconversion rates (SCRs) for QIV were 80.4% (95% confidence interval [CI], 73.0%-86.6%), 72.0% (95% CI, 63.9%-79.2%), 86.0% (95% CI, 79.2%-91.2%), and 66.4% (95% CI, 58.1%-74.1%) for A/H1N1, A/H3N2, B/Yamagata, and B/Victoria, respectively. Quadrivalent influenza vaccines demonstrated immunogenic superiority over TIV for B/Victoria with a geometric mean titer ratio of 4.73 (95% CI, 3.73%-5.99%) and SCR difference of 54.02% (95% CI, 43.88%-62.87%). Safety was similar between the vaccine groups despite the QIV's higher antigen content. No serious adverse events were reported related to vaccination.
[h=4]CONCLUSIONS:[/h] Quadrivalent influenza vaccine (15 ?g HA/strain) was immunogenic with an acceptable safety profile. The next phase of its development in children 6-35 months of age is a phase III trial in countries where it is not yet licensed. In countries where it is already licensed, a switch from TIV to QIV would provide broader protection in this vulnerable group.
? The Author 2015. Published by Oxford University Press on behalf of the Pediatric Infectious Diseases Society.
[h=4]KEYWORDS:[/h] children; immunogenicity; influenza; quadrivalent; vaccine
PMID: 26407273 [PubMed - as supplied by publisher]
[h=1]Immunogenicity and Safety of an Inactivated Quadrivalent Influenza Vaccine in US Children 6-35 Months of Age During 2013-2014: Results From A Phase II Randomized Trial.[/h] Wang L[SUP]1[/SUP], Chandrasekaran V[SUP]2[/SUP], Domachowske JB[SUP]3[/SUP], Li P[SUP]2[/SUP], Innis BL[SUP]1[/SUP], Jain VK[SUP]1[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Viruses from 2 influenza B lineages co-circulate, leading to suboptimal protection with trivalent influenza vaccines (TIV). Quadrivalent influenza vaccines (QIV) containing both lineages offer broader protection.
[h=4]METHODS:[/h] We compared inactivated seasonal QIV versus TIV (15 and 7.5 μg hemagglutinin [HA] for each influenza strain, respectively) in a phase II randomized (1 : 1), observer-blind trial in US children 6-35 months of age (identifier NCT01974895). The primary objective was to evaluate immune responses induced by QIV for the 4 vaccine strains 28 days after completion of vaccination. A secondary objective was to demonstrate superiority of QIV versus TIV for the B/Victoria strain contained in QIV but not TIV. Immunogenicity was evaluated in the per-protocol cohort (N = 280), and safety was evaluated in the intent-to-treat cohort (N = 314).
[h=4]RESULTS:[/h] Seroconversion rates (SCRs) for QIV were 80.4% (95% confidence interval [CI], 73.0%-86.6%), 72.0% (95% CI, 63.9%-79.2%), 86.0% (95% CI, 79.2%-91.2%), and 66.4% (95% CI, 58.1%-74.1%) for A/H1N1, A/H3N2, B/Yamagata, and B/Victoria, respectively. Quadrivalent influenza vaccines demonstrated immunogenic superiority over TIV for B/Victoria with a geometric mean titer ratio of 4.73 (95% CI, 3.73%-5.99%) and SCR difference of 54.02% (95% CI, 43.88%-62.87%). Safety was similar between the vaccine groups despite the QIV's higher antigen content. No serious adverse events were reported related to vaccination.
[h=4]CONCLUSIONS:[/h] Quadrivalent influenza vaccine (15 ?g HA/strain) was immunogenic with an acceptable safety profile. The next phase of its development in children 6-35 months of age is a phase III trial in countries where it is not yet licensed. In countries where it is already licensed, a switch from TIV to QIV would provide broader protection in this vulnerable group.
? The Author 2015. Published by Oxford University Press on behalf of the Pediatric Infectious Diseases Society.
[h=4]KEYWORDS:[/h] children; immunogenicity; influenza; quadrivalent; vaccine
PMID: 26407273 [PubMed - as supplied by publisher]