title: Superior immunogenicity profile of the new intradermal influenza vaccine compared to the standard subcutaneous vaccine in subjects 65 years and older: A randomized controlled phase III study.
abstract: BACKGROUND
  Although the elderly are at high risk for influenza, the immunogenicity in the elderly is lower than that in younger adults. We developed the new type of seasonal influenza vaccine with the novel intradermal (ID) injection system. In the previous exploratory phase I/II study of the ID vaccine with a dose of 15 μg HA per strain showed the superior immunogenicity profile to that of the standard subcutaneous (SC) injection vaccine in subjects aged 20 years and older.
  
  
  METHODS
  In this multicenter, randomized, double-blind, active controlled study, 900 adults aged 65 years and older were randomized at an equal ratio to either the ID vaccine group or the licensed standard SC vaccine group. Immunogenicity was assessed using serum hemagglutination inhibition (HAI) titers. The co-primary endpoints were the geometrical mean titers (GMT) and the seroconversion rates (SCR) of HAI titers against 3 vaccine strains on Day 21 (21 days after vaccination). To evaluate the early phase immunogenicity, the GMTs and SCRs on Day 7 were also assessed in the same way as the secondary endpoints.
  
  
  RESULTS
  The superiority of the ID vaccine in the GMTs and SCRs were demonstrated in all 3 vaccine strains both on Day 7 and Day 21. The frequency of any injection-site reactions was higher in the ID vaccine group, while the severity of injection-site reactions and the frequency of systemic AEs were comparable between the ID and the SC vaccine groups.
  
  
  CONCLUSIONS
  A single-dose of the influenza vaccine with the novel ID injection system and a dose of 15 μg HA was suggested as an appropriate regimen for clinical use in influenza prevention and associated disease burden reduction. It was also suggested that the new ID vaccine has the potential to replace the standard influenza vaccine from the view point of immunogenicity and safety.
  
  
  BACKGROUND
  JAPIC Clinical Trials Information (JapicCTI-142493).
authors.affiliation: Daiichi Sankyo Co. Ltd., Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Arakane
authors.affiliation: Daiichi Sankyo Co. Ltd., Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Annaka
authors.affiliation: Daiichi Sankyo Co. Ltd., Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Takahama
authors.affiliation: Daiichi Sankyo Co. Ltd., Japan.
authors.forename: Katsuyasu
authors.initials: K
authors.lastname: Ishida
authors.affiliation: Daiichi Sankyo Co. Ltd., Japan.
authors.forename: Michiharu
authors.initials: M
authors.lastname: Yoshiike
authors.affiliation: Kitasato Institute for Life Sciences, Laboratory of Viral Infection, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Nakayama
authors.affiliation: Daiichi Sankyo Co. Ltd., Japan. Electronic address: Takeshita.fumihiko.aw@daiichisankyo.co.jp.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Takeshita
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood; D004311:Double-Blind Method; D005260:Female; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D007252:Influenza Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control*; D007271:Injections, Intradermal; D007279:Injections, Subcutaneous; D008297:Male; D016896:Treatment Outcome
chemical_list: D000914:Antibodies, Viral; D007252:Influenza Vaccines
keywords: Clinical trial; Influenza; Intradermal vaccine; Novel device