Vol.64 No.2 March 2016
A phase I/II clinical study on ASP7374 (recombinant influenza hemagglutinin vaccine) in Japanese adults
1)Department of Infectious Diseases, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, Japan
2)Global Development, Astellas Pharma Inc.
Abstract
The immunogenicity and safety of a single subcutaneous injection (2 dose regimens) and intramuscular injection (1 dose regimen) of a new influenza vaccine, ASP7374, were compared in this clinical study among healthy adults to determine a clinically recommended dose.
Adult healthy males and females (age range: 20-49 years) were randomly allocated to one of the following groups in a 1: 1: 1 ratio: group 1, a single subcutaneous injection of ASP7374 15 μg/strain; group 2, a single subcutaneous injection of ASP7374 45 μg/strain; or group 3, a single intramuscular injection of ASP7374 45 μg/strain. Subjects were treated under open label conditions with intramuscular injections and double-blinded conditions with subcutaneous injection.
The geometric mean hemagglutination-inhibition(HI) antibody titer 28 days postvaccination was higher than that at baseline in all treatment groups among the strains (A/H1N1, A/H3N2, and B strain). The geometric mean HI antibody titer ratio (postvaccination/baseline) and seroconversion rate were highest with the intramuscular injection of ASP7374 45 μg/strain with any vaccine strain, followed by the subcutaneous injection of ASP7374 45 μg/strain and 15 μg/strain. All of the treatment groups had nearly 100% seroprotection rate 28 days postvaccination. The proportion of subjects with adverse events was higher in the subcutaneous injection groups (60.0% in the ASP7374 15 μg/strain group and 65.5% in the 45 μg/strain group) than in the intramuscular injection group (43.6%). A similar tendency was observed for local and systemic reactions. Most of the local/systemic reactions occurred within 2 days of administering the injections, and they resolved within 8 days of onset. In conclusion, the ASP7374 influenza vaccine injection had adequate immunogenicity and a well-tolerated safety profile. The subcutaneous injection of ASP7374 45 μg/strain and intramuscular injection of ASP7374 45 μg/strain appeared to be the clinically recommended doses.
Key word
influenza, HA vaccine, phase I/II study, adult
Received
June 29, 2015
Accepted
November 17, 2015
Jpn. J. Chemother. 64 (2): 244-252, 2016
