title: A Phase I, randomized, open-label study to evaluate the safety and immunogenicity of an enterovirus 71 vaccine.
abstract: BACKGROUND
  Large-scale outbreaks of enterovirus 71 (EV71) infections have occurred in Asia-Pacific regions. Severe complications include encephalitis and poliomyelitis-like paralysis, cardiopulmonary collapse, and death, necessitating an effective vaccine against EV71.
  
  
  METHODS
  In this randomized Phase I study, we evaluated the safety and immunogenicity of an inactivated alum-adjuvanted EV71 whole-virus vaccine produced on Vero cell cultures. Sixty healthy volunteers aged 20-60 years received two doses of vaccine, administered 21 days apart. Each dose contained either 5 μg of EV71 antigen with 150 μg of adjuvant (Group A05) or 10 μg of EV71 antigen with 300 μg of adjuvant (Group B10). Serologic analysis was performed at baseline, day 21, and day 42.
  
  
  RESULTS
  There were no serious adverse events. Mild injection site pain and myalgia were the most common adverse events with either vaccine formulation. The immunogenicity data showed that 90% of vaccine recipients have a 4-fold or greater increase in neutralization antibody titers (NT) after the first dose, without a further increase in NT after the second dose. The seroconversion rates on day 21 and day 42 were 86.7% and 93.1% respectively, in Group A05, and 92.9% and 96.3%, respectively, in Group B10. Thus, 5 μg and 10 μg of the EV71 vaccine can induce a remarkable immune response in healthy adults after only the first vaccination.
  
  
  CONCLUSIONS
  The 5 μg and 10 μg adjuvanted EV71 vaccines are generally safe and immunogenic in healthy adults. (ClinicalTrials.gov number, NCT01268787).
authors.affiliation: Department of Internal Medicine, Far Eastern Memorial Hospital, 21, Section 2, Nanya South Road, New Taipei City, Taiwan.
authors.forename: Aristine
authors.initials: A
authors.lastname: Cheng
authors.forename: Chang-Phone
authors.initials: CP
authors.lastname: Fung
authors.forename: Chia-Chyi
authors.initials: CC
authors.lastname: Liu
authors.forename: Yi-Tsung
authors.initials: YT
authors.lastname: Lin
authors.forename: Hsih-Yeh
authors.initials: HY
authors.lastname: Tsai
authors.forename: Shan-Chwen
authors.initials: SC
authors.lastname: Chang
authors.forename: Ai-Hsiang
authors.initials: AH
authors.lastname: Chou
authors.forename: Jui-Yuan
authors.initials: JY
authors.lastname: Chang
authors.forename: Ren-Huei
authors.initials: RH
authors.lastname: Jiang
authors.forename: Yi-Chin
authors.initials: YC
authors.lastname: Hsieh
authors.forename: Ih-Jen
authors.initials: IJ
authors.lastname: Su
authors.forename: Pele Choi-Sing
authors.initials: PC
authors.lastname: Chong
authors.forename: Szu-Min
authors.initials: SM
authors.lastname: Hsieh
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage; D000328:Adult; D000534:Alum Compounds; D000818:Animals; D000917:Antibody Formation / Q000276:immunology; D002522:Chlorocebus aethiops; D004770:Enterovirus / Q000276:immunology*; D004769:Enterovirus Infections / Q000276:immunology / Q000517:prevention & control; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D014611:Vaccination / Q000009:adverse effects*; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D014709:Vero Cells; D014765:Viral Vaccines / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D055815:Young Adult
chemical_list: D000276:Adjuvants, Immunologic; D000534:Alum Compounds; D015164:Vaccines, Inactivated; D014765:Viral Vaccines; C041524:aluminum sulfate