tetano
Editor, Senior Moderator
Vaccine. 2014 Nov 21. pii: S0264-410X(14)01543-6. doi: 10.1016/j.vaccine.2014.11.018. [Epub ahead of print]
Immunogenicity of heterologous H5N1 influenza booster vaccination 6 or 18 months after primary vaccination in adults: A randomized controlled clinical trial.
Langley JM1, Frenette L2, Jeanfreau R3, Halperin SA4, Kyle M5, Chu L6, McNeil S4, Dram? M7, Moris P8, Fries L9, Vaughn DW8.
Author information
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 7.5μg 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 3.75μg 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.
Copyright ? 2014. Published by Elsevier Ltd.
KEYWORDS:
Heterologous booster; Immunogenicity; Influenza A/H5N1 vaccine
PMID:
25448092
[PubMed - as supplied by publisher]
Free full text
http://www.ncbi.nlm.nih.gov/pubmed/25448092
Immunogenicity of heterologous H5N1 influenza booster vaccination 6 or 18 months after primary vaccination in adults: A randomized controlled clinical trial.
Langley JM1, Frenette L2, Jeanfreau R3, Halperin SA4, Kyle M5, Chu L6, McNeil S4, Dram? M7, Moris P8, Fries L9, Vaughn DW8.
Author information
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 7.5μg 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 3.75μg 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.
Copyright ? 2014. Published by Elsevier Ltd.
KEYWORDS:
Heterologous booster; Immunogenicity; Influenza A/H5N1 vaccine
PMID:
25448092
[PubMed - as supplied by publisher]
Free full text
http://www.ncbi.nlm.nih.gov/pubmed/25448092