Journal of Infectious Diseases
Volume 211 Issue 5 March 1, 2015
http://jid.oxfordjournals.org/content/current

AS03B-Adjuvanted H5N1 Influenza Vaccine in Children 6 Months Through 17 Years of Age: A Phase 2/3 Randomized, Placebo-Controlled, Observer-Blinded Trial
Pope Kosalaraksa1,a, Robert Jeanfreau2,a, Louise Frenette3, Mamadou Drame4, Miguel Madariaga4,b, Bruce L. Innis4, Olivier Godeaux5, Patricia Izurieta5 and David W. Vaughn6
Author Affiliations
1Department of Pediatrics, Khon Kaen University, Thailand
2Internal Medicine, Benchmark Research, Metairie, Louisiana
3QT Research, Sherbrooke, Canada
4GlaxoSmithKline Vaccines, King of Prussia, Pennsylvania
5GlaxoSmithKline Vaccines, Wavre
6GlaxoSmithKline Vaccines, Rixensart, Belgium
Presented in part: 50th Annual Meeting of the Infectious Diseases Society of America, San Diego, California, 17–21 October 2012; Second WHO Integrated Meeting on Development and Clinical Trials of Influenza Vaccines That Introduce Broadly Protective and Long-Lasting Immune Responses, Geneva, Switzerland, 5–7 May 2014.
a P. K. and R. J. are co–first authors.
b Present affiliation: Infectious Diseases Department, Naples Community Hospital, Florida.
Abstract
Background.
This phase 2/3, randomized, placebo-controlled, observer-blinded study assessed the immunogenicity, reactogenicity, and safety of an inactivated, split-virion H5N1 influenza vaccine (A/Indonesia/5/2005) in children aged 6 months through 17 years.
Methods. Children received 2 influenza vaccine doses 21 days apart, each containing 1.9 µg of hemagglutinin and AS03B adjuvant (5.93 mg of α-tocopherol). The randomization ratio was 8:3 for vaccine to placebo, with equal allocation between 3 age strata (6–35 months, 3–8 years, and 9–17 years). Immunogenicity against the vaccine strain was assessed 21 days after the first and second vaccine doses for all vaccinees, at day 182 for half, and at day 385 for the remaining half. Reactogenicity after each dose and safety up to 1 year after vaccination were evaluated.
Results.
Within each age stratum, the lower limit of the 98.3% confidence interval for the day 42 seroprotection rate was ≥70%, thus fulfilling the US and European licensure criteria. The immune responses elicited by vaccine persisted well above baseline levels for 1 year. The vaccine was more reactogenic than placebo, but no major safety concerns were identified.
Conclusions.
AS03B-adjuvanted H5N1 influenza vaccine was immunogenic and showed an acceptable safety profile in all age groups studied.
Clinical Trials Registration. NCT01310413.