Change search
ReferencesLink to record
Permanent link

Direct link
Safety and immunogenicity of two different doses of a Vero cell-derived, whole virus clade 2 H5N1 (A/Indonesia/05/2005) influenza vaccine.
Institute of Public Health, University of Heidelberg, Germany.ORCID iD: 0000-0003-0362-5375
Show others and affiliations
2012 (English)In: Vaccine, ISSN 0264-410X, E-ISSN 1873-2518, Vol. 30, no 2, 329-35 p.Article in journal (Refereed) Published
Abstract [en]

A successful vaccine development strategy for areas with clustered H5N1 events requires conduct of vaccine trials in potentially non-naïve subjects and evaluation of post-vaccination responsiveness. An open-label, randomized, phase I/II study therefore assessed the immunogenicity and safety of two different dose levels of an inactivated, non-adjuvanted, whole virus clade 2.1 (A/Indonesia/05/2005) H5N1 Vero cell-derived influenza vaccine in healthy adults (21-45 years) from a region where the virus has been circulating (Hong Kong) as well as Singapore. Subjects (N=110) were randomized 1:1 to receive two vaccinations with either 3.75 μg or 7.5 μg H5N1 haemagglutinin antigen 21 days apart. Safety, immunogenicity (microneutralization [MN] and single radial haemolysis [SRH] at baseline and post-vaccination) and cross-reactivity against a heterologous clade 1 strain (A/Vietnam/1203/2004) of the vaccine were assessed. Pre-existing immunity to the vaccine strain was 14% which is higher than previously reported for these regions. Two vaccinations with either vaccine formulation induced high seroprotection rates (MN titre ≥ 1:20) against the vaccine strain A/Indonesia/05/2005: 82.7% and 86.5% in the 3.75 μg and 7.5 μg dose groups. Seroconversion rates and fold increase exceeded the CPMP criterion of >40% and >2.5 for MN and SRH in both dose groups after the second vaccination, while the seroprotection rate in the 7.5 μg dose group determined by SRH was only marginally lower (69.2%) than the CPMP criterion of >70%. Thus, 11 of 12 CHMP criteria were fulfilled. A cross-reactive antibody response against the heterologous A/Vietnam/1203/2004 strain was demonstrated after the second vaccination (>21% by MN and ≥ 25% by SRH). Persistence of antibodies against the vaccine strain was also demonstrated 6 months after the first vaccination, indicating that a booster vaccination would be effective in those who have received two priming doses. No serious adverse events were reported. The H5N1 influenza vaccine against clade 2.1 strain A/Indonesia/05/2005 was well tolerated and immunogenic after two vaccinations, and induced a cross-neutralizing antibody response, with no dose effect.

Place, publisher, year, edition, pages
Elsevier, 2012. Vol. 30, no 2, 329-35 p.
National Category
Public Health, Global Health, Social Medicine and Epidemiology
URN: urn:nbn:se:umu:diva-53184DOI: 10.1016/j.vaccine.2011.10.088PubMedID: 22080174OAI: diva2:510195
Available from: 2012-03-15 Created: 2012-03-15 Last updated: 2015-04-29Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMed

Search in DiVA

By author/editor
Wilder-Smith, Annelies
In the same journal
Public Health, Global Health, Social Medicine and Epidemiology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 25 hits
ReferencesLink to record
Permanent link

Direct link