title: Immunogenicity and persistence of immunity of a quadrivalent Human Papillomavirus (HPV) vaccine in immunocompromised children.
abstract: The aim of this study was to determine the immunogenicity and reactogenicity of HPV vaccine in immunocompromised children.
  
  
  
  A multi-centre clinical trial was conducted in three paediatric hospitals in Australia. Unvaccinated children 5-18years of age attending one of three paediatric hospitals with a range of specified conditions associated with immunosuppression were included. Quadrivalent HPV vaccine (Gardasil) was given to the participants and serum anti-HPV antibody levels were measured at baseline (before first dose), 7 and 24months after the first dose of vaccine.
  
  
  
  Fifty-nine participants were enrolled across the three paediatric hospitals and among those one was seropositive to types 6, 11 and 16 at baseline. Seven months after the first dose, seroconversion rates were 93.3%, 100%, 100% and 88.9% for type 6, 11, 16 and 18 respectively. The corresponding rates at 24month follow up were 82.2%, 91.1%, 91.1% and 68.9%. The greatest increase in geometric mean titre (GMT) was for type 16, followed by type 11. GMTs declined over the following months, but remained more than fourfold higher for all serotypes compared to baseline titres at 24months post vaccination. Injection site erythema, pain and swelling were commonly reported local adverse events and were less common after each dose. Few participants reported systemic adverse events, and minor disease flare occurred in two participants. One child developed a squamous cell oral carcinoma during follow up, but tissue was unable to be tested for HPV.
  
  
  
  Immunosuppressed children had an adequate immunogenic response to Quadrivalent HPV vaccine regardless of age and the cause of immunosuppression. HPV related cancers occur at higher frequency and earlier in immunosuppressed patients, so early vaccination and optimal scheduling should be further studied in such children.
  
  
  
  NCT02263703 (ClinicalTrials.gov).
authors.affiliation: School of Public Health and Community Medicine, Faculty of Medicine, University of New South Wales, Kensington, NSW 2052, Australia; College of Public Service and Community Solutions, Arizona State University, USA. Electronic address: r.macintyre@unsw.edu.au.
authors.forename: C Raina
authors.initials: CR
authors.lastname: MacIntyre
authors.affiliation: Dept Gastroenterology Children's Hospital at Westmead, Hawkesbury Rd, Westmead NSW 2145, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Shaw
authors.affiliation: Nephrology, Sydney Children's Hospital, Randwick, High St, Randwick NSW 2031, Australia; School of Women's & Children's Health, Faculty of Medicine, University of New South Wales, Kensington, NSW 2052, Australia.
authors.forename: Fiona E
authors.initials: FE
authors.lastname: Mackie
authors.affiliation: The Women's and Children's Hospital and Robinson Research Institute and School of Medicine, The University of Adelaide, 55 King William Road, North Adelaide 5006, Australia.
authors.forename: Christina
authors.initials: C
authors.lastname: Boros
authors.affiliation: The Women's and Children's Hospital and Robinson Research Institute and School of Medicine, The University of Adelaide, 55 King William Road, North Adelaide 5006, Australia.
authors.forename: Helen
authors.initials: H
authors.lastname: Marshall
authors.affiliation: School of Public Health and Community Medicine, Faculty of Medicine, University of New South Wales, Kensington, NSW 2052, Australia.
authors.forename: Michelle
authors.initials: M
authors.lastname: Barnes
authors.affiliation: School of Public Health and Community Medicine, Faculty of Medicine, University of New South Wales, Kensington, NSW 2052, Australia.
authors.forename: Holly
authors.initials: H
authors.lastname: Seale
authors.affiliation: Nephrology, Sydney Children's Hospital, Randwick, High St, Randwick NSW 2031, Australia; School of Women's & Children's Health, Faculty of Medicine, University of New South Wales, Kensington, NSW 2052, Australia.
authors.forename: Sean E
authors.initials: SE
authors.lastname: Kennedy
authors.affiliation: School of Public Health and Community Medicine, Faculty of Medicine, University of New South Wales, Kensington, NSW 2052, Australia.
authors.forename: Aye
authors.initials: A
authors.lastname: Moa
authors.affiliation: School of Public Health and Community Medicine, Faculty of Medicine, University of New South Wales, Kensington, NSW 2052, Australia.
authors.forename: Andrew
authors.initials: A
authors.lastname: Hayen
authors.affiliation: School of Public Health and Community Medicine, Faculty of Medicine, University of New South Wales, Kensington, NSW 2052, Australia.
authors.forename: Abrar Ahmad
authors.initials: AA
authors.lastname: Chughtai
authors.affiliation: Dept Gastroenterology Children's Hospital at Westmead, Hawkesbury Rd, Westmead NSW 2145, Australia.
authors.forename: Edward V
authors.initials: EV
authors.lastname: O'Loughlin
authors.affiliation: Dept Gastroenterology Children's Hospital at Westmead, Hawkesbury Rd, Westmead NSW 2145, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Stormon
mesh_terms: D000293:Adolescent; D000914:Antibodies, Viral / Q000097:blood; D001315:Australia / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D000068857:Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18 / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology*; D052162:Human papillomavirus 16 / Q000276:immunology*; D006801:Humans; D016867:Immunocompromised Host; D000071497:Immunogenicity, Vaccine; D008297:Male; D030361:Papillomavirus Infections / Q000453:epidemiology / Q000276:immunology* / Q000517:prevention & control* / Q000821:virology; D000069078:Seroconversion; D013997:Time Factors; D014611:Vaccination
chemical_list: D000914:Antibodies, Viral; D000068857:Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18
keywords: Adolescents; Cancer; Human Papillomavirus; Immunisation; Immunodeficiency; Vaccine; Warts