title: Safety, tolerability, and immunogenicity after 1 and 2 doses of zoster vaccine in healthy adults ≥60 years of age.
abstract: BACKGROUND
  Incidence and severity of herpes zoster (HZ) and postherpetic neuralgia increase with age, associated with age-related decrease in immunity to varicella-zoster virus (VZV). One dose of zoster vaccine (ZV) has demonstrated substantial protection against HZ; this study examined impact of a second dose of ZV.
  
  
  METHODS
  Randomized, double-blind, multicenter study with 210 subjects ≥60 years old compared immunity and safety profiles after one and two doses of ZV, separated by 6 weeks, vs. placebo. Immunogenicity was evaluated using VZV interferon-gamma (IFN-γ) enzyme-linked immunospot (ELISPOT) assay and VZV glycoprotein enzyme-linked immunosorbent antibody (gpELISA) assay. Adverse experiences (AEs) were recorded on a standardized Vaccination Report Card.
  
  
  RESULTS
  No serious vaccine-related AEs occurred. VZV IFN-γ ELISPOT geometric mean count (GMC) of spot-forming cells per 10(6) peripheral blood mononuclear cells increased in the ZV group from 16.9 prevaccination to 49.5 and 32.8 at 2 and 6 weeks postdose 1, respectively. Two weeks, 6 weeks and 6 months postdose 2, GMC was 44.3, 42.9, and 36.5, respectively. GMC in the placebo group did not change during the study. The peak ELISPOT response occurred ∼2 weeks after each ZV dose. The gpELISA geometric mean titers (GMTs) in the ZV group were higher than in the placebo group at 6 weeks after each dose. Correlation between the IFN-γ ELISPOT and gpELISA assays was poor.
  
  
  CONCLUSIONS
  ZV was generally well-tolerated and immunogenic in adults ≥60 years old. A second dose of ZV was generally safe, but did not boost VZV-specific immunity beyond levels achieved postdose 1.
authors.affiliation: Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Joost N
authors.initials: JN
authors.lastname: Vermeulen
authors.forename: Joep M A
authors.initials: JM
authors.lastname: Lange
authors.forename: Stephen K
authors.initials: SK
authors.lastname: Tyring
authors.forename: Patrick H
authors.initials: PH
authors.lastname: Peters
authors.forename: Margaret
authors.initials: M
authors.lastname: Nunez
authors.forename: Gregory
authors.initials: G
authors.lastname: Poland
authors.forename: Myron J
authors.initials: MJ
authors.lastname: Levin
authors.forename: Carrie
authors.initials: C
authors.lastname: Freeman
authors.forename: Ira
authors.initials: I
authors.lastname: Chalikonda
authors.forename: Jianjun
authors.initials: J
authors.lastname: Li
authors.forename: Jeffrey G
authors.initials: JG
authors.lastname: Smith
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Caulfield
authors.forename: Jon E
authors.initials: JE
authors.lastname: Stek
authors.forename: Ivan S F
authors.initials: IS
authors.lastname: Chan
authors.forename: Rupert
authors.initials: R
authors.lastname: Vessey
authors.forename: Florian P
authors.initials: FP
authors.lastname: Schödel
authors.forename: Paula W
authors.initials: PW
authors.lastname: Annunziato
authors.forename: Katia
authors.initials: K
authors.lastname: Schlienger
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Silber
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood; D004311:Double-Blind Method; D004797:Enzyme-Linked Immunosorbent Assay; D058501:Enzyme-Linked Immunospot Assay; D005260:Female; D053061:Herpes Zoster Vaccine / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D014645:Herpesvirus 3, Human / Q000276:immunology; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010919:Placebos / Q000008:administration & dosage; D014611:Vaccination / Q000009:adverse effects* / Q000379:methods*
chemical_list: D000914:Antibodies, Viral; D053061:Herpes Zoster Vaccine; D010919:Placebos; D007371:Interferon-gamma