title: Evaluation of the Safety and Immunogenicity of a Candidate Pandemic Live Attenuated Influenza Vaccine (pLAIV) Against Influenza A(H7N9).
abstract: BACKGROUND
  We evaluated a candidate A/Anhui/2013(H7N9) pandemic live attenuated influenza vaccine (pLAIV) in healthy adults, and assessed the ability of 1 or 2 doses to induce immune memory.
  
  
  METHODS
  Healthy subjects in 2 age groups (18-49 years and 50-70 years) with undetectable hemagglutination-inhibiting (HAI) antibody to H7N9 were enrolled. Younger subjects received either 1 or 2 intranasal doses of 10(7.0) fluorescent focus units of A/Anhui/1/2013 pLAIV, while older subjects received a single dose. All subjects received a single 30-µg dose of unadjuvanted, antigenically matched A/Shanghai2/2013(H7N9) pandemic inactivated influenza vaccine (pIIV) 12 weeks after their first dose of pLAIV.
  
  
  RESULTS
  Both vaccines were well tolerated. Serum HAI antibody responses were detected in 0 of 32 younger subjects and 1 of 17 older subjects after 1 dose of pLAIV and in 2 of 16 younger subjects after a second dose. Strong serum antibody responses were detected after a single subsequent dose of pIIV that was broadly reactive against H7 influenza viruses.
  
  
  CONCLUSIONS
  An A(H7N9) pLAIV candidate was safe in both age groups. Priming with pLAIV resulted in responses to subsequent pIIV that exceeded those seen in naive subjects in previous reports. The A(H7N9) pLAIV induces strong immune memory that can be demonstrated by exposure to subsequent antigenic challenge.
  
  
  BACKGROUND
  NCT01995695 and NCT02274545.
authors.affiliation: Department of Medicine, University of Rochester Medical Center, New York.
authors.forename: Mahdee
authors.initials: M
authors.lastname: Sobhanie
authors.affiliation: Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda.
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Matsuoka
authors.affiliation: Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, Victoria, Australia.
authors.forename: Sinthujan
authors.initials: S
authors.lastname: Jegaskanda
authors.affiliation: Department of Medicine, University of Rochester Medical Center, New York.
authors.forename: Theresa
authors.initials: T
authors.lastname: Fitzgerald
authors.affiliation: Medimmune, Gaithersburg, Maryland.
authors.forename: Raburn
authors.initials: R
authors.lastname: Mallory
authors.affiliation: Medimmune, Gaithersburg, Maryland.
authors.forename: Zhongying
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda.
authors.forename: Catherine
authors.initials: C
authors.lastname: Luke
authors.affiliation: Department of Medicine, University of Rochester Medical Center, New York.
authors.forename: John
authors.initials: J
authors.lastname: Treanor
authors.affiliation: Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda.
authors.forename: Kanta
authors.initials: K
authors.lastname: Subbarao
mesh_terms: D000281:Administration, Intranasal; D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging; D000914:Antibodies, Viral / Q000097:blood; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D064766:Influenza A Virus, H7N9 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000009:adverse effects* / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D058873:Pandemics / Q000517:prevention & control*; D013997:Time Factors; D014779:Virus Replication / Q000502:physiology; D017201:Virus Shedding; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral; D007252:Influenza Vaccines
keywords: immune memory; live vaccine; pandemic influenza