Immunogenicity of heterologous H5N1 influenza booster vaccination 6 or 18 months after primary vaccination in adults: a randomized controlled clinical trial.
Vaccine
; 33(4): 559-67, 2015 Jan 15.
Article
em En
| MEDLINE
| ID: mdl-25448092
ABSTRACT
BACKGROUND:
Highly pathogenic avian influenza A/H5N1 viruses continue to circulate in birds and infect humans causing serious illness and death.METHODS:
In this randomized, observer-blinded study, adults ≥18 years of age (n=841) received 3.75 or 7.5 µg hemagglutinin antigen (HA) of an AS03-adjuvanted (AS03A or AS03B) A/Indonesia/5/2005 H5N1 (subclade 2.1) vaccine (priming), followed by the same HA dose of AS03-adjuvanted A/turkey/Turkey/1/05 H5N1 (clade 2.2) influenza vaccine as a booster 6 or 18 months after priming; an unprimed group received placebo at Day 0, and 3.75 µg HA of AS03A-adjuvanted booster vaccine at 6 and 18 months. Antibody responses were assessed by hemagglutination-inhibition assay (HI). Microneutralization (MN) antibody and cellular immunoassays were assessed in a subset of participants.RESULTS:
Geometric mean titers (GMTs) and seroconversion rates (SCRs) were higher in primed vs. unprimed subjects against the booster strain 10 days following booster vaccination at month 6 and month 18. After the booster at 18 months, the lower limit of the 97.5% confidence interval for the difference in SCR and GMT ratios between primed and unprimed subjects was >15% and >2.0, respectively, fulfilling the primary endpoint criteria for superiority against the booster strain. MN and cellular immune responses corresponded with the immunogenicity seen in HI measures.CONCLUSIONS:
Adults primed with a dose-sparing oil-in-water adjuvanted H5N1 subclade vaccine had rapid and durable antibody responses to a heterologous subclade boosting vaccine given 6 or 18 months later.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Vacinas contra Influenza
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Imunização Secundária
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Influenza Humana
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Virus da Influenza A Subtipo H5N1
Tipo de estudo:
Clinical_trials
Limite:
Adolescent
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Adult
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Aged
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Aged80
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Animals
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Female
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Humans
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Male
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Middle aged
País/Região como assunto:
Asia
Idioma:
En
Revista:
Vaccine
Ano de publicação:
2015
Tipo de documento:
Article