The first four authors contributed equally to the work.
Immunogenicity and safety of a 2009 pandemic influenza A (H1N1) monovalent vaccine in Chinese infants aged 6–35 months: a randomized, double-blind, controlled phase I clinical trial
Article first published online: 8 NOV 2012
© 2012 John Wiley & Sons Ltd
Influenza and Other Respiratory Viruses
Volume 7, Issue 6, pages 1297–1307, November 2013
How to Cite
Li, Y.-P., Li, W., Liang, X.-F., Liu, Y., Huang, X.-C., Li, C.-G., Li, R.-C., Wang, J.-Z., Wang, H.-Q. and Yin, W.-D. (2013), Immunogenicity and safety of a 2009 pandemic influenza A (H1N1) monovalent vaccine in Chinese infants aged 6–35 months: a randomized, double-blind, controlled phase I clinical trial. Influenza and Other Respiratory Viruses, 7: 1297–1307. doi: 10.1111/irv.12028
- Issue published online: 5 NOV 2013
- Article first published online: 8 NOV 2012
- Accepted 26 August 2012. Published Online 7 November 2012.
- National High Technology Research
- Center for Disease Control and Prevention. Grant Number: 2010AA022908
- Chinese infant;
- pandemic influenza vaccine;
- seasonal influenza vaccine
Please cite this paper as: Li et al. (2012) Immunogenicity and safety of a 2009 pandemic influenza A (H1N1) monovalent vaccine in Chinese infants aged 6–35 months: a randomized, double-blind, controlled phase I clinical trial. Influenza and Other Respiratory Viruses DOI: 10.1111/irv.12028.
Objectives The goal of this double-blind, randomized, controlled clinical trial was to assess the safety and immunogenicity of two different doses of a monovalent split-virion 2009 pandemic influenza A/H1N1 vaccine without adjuvant in Chinese infants aged 6-35 months.
Design and setting Subjects were randomly assigned to receive either a 2009 pandemic (H1N1) vaccine containing 7.5 or 15 μg haemagglutinin (HA) or a seasonal influenza vaccine. 2 doses of the H1N1 vaccines or the seasonal influenza vaccine were given 21 days apart in younger infants aged 6-23 months or older infants aged 24-35 months.
Sample Serum samples were collected immediately before the first injection and before and 21 days after the second injection.
Main outcome measures Primary outcomes were haemagglutinin inhibition (HI) antibody responses 21 days following each vaccination. Safety was monitoring throughout the study.
Results The first vaccination of 7.5 μg and 15 μg H1N1 vaccine induced seroprotective antibody titers (HI titers ≥ 1: 40) in 42.9-57.4% of younger infants and 49.1-61.0% older infants. Immune responses after completion of the two dose schedule were comparable in both age groups with seroprotective rates of 91-98% in each vaccine and age group and GMTs of 173-263. The H1N1 vaccine elicited similar rates of local and systemic adverse reactions as the seasonal influenza vaccine.
Conclusions The 2009 pandemic influenza A /H1N1 vaccine were highly immunogenic in infants aged 6-35 months, and displayed a safety and reactogenicity profile similar to the seasonal influenza vaccine.
Trial registration ClinicalTrial.gov identifier: NCT01047202