title: Health and Economic Impact of Switching from a 4-Valent to a 9-Valent HPV Vaccination Program in the United States.
abstract: BACKGROUND
  Randomized clinical trials have shown the 9-valent human papillomavirus (HPV) vaccine to be highly effective against types 31/33/45/52/58 compared with the 4-valent. Evidence on the added health and economic benefit of the 9-valent is required for policy decisions. We compare population-level effectiveness and cost-effectiveness of 9- and 4-valent HPV vaccination in the United States.
  
  
  METHODS
  We used a multitype individual-based transmission-dynamic model of HPV infection and disease (anogenital warts and cervical, anogenital, and oropharyngeal cancers), 3% discount rate, and societal perspective. The model was calibrated to sexual behavior and epidemiologic data from the United States. In our base-case, we assumed 95% vaccine-type efficacy, lifelong protection, and a cost/dose of $145 and $158 for the 4- and 9-valent vaccine, respectively. Predictions are presented using the mean (80% uncertainty interval [UI] = 10(th)-90(th) percentiles) of simulations.
  
  
  RESULTS
  Under base-case assumptions, the 4-valent gender-neutral vaccination program is estimated to cost $5500 (80% UI = 2400-9400) and $7300 (80% UI = 4300-11 000)/quality-adjusted life-year (QALY) gained with and without cross-protection, respectively. Switching to a 9-valent gender-neutral program is estimated to be cost-saving irrespective of cross-protection assumptions. Finally, the incremental cost/QALY gained of switching to a 9-valent gender-neutral program (vs 9-valent girls/4-valent boys) is estimated to be $140 200 (80% UI = 4200->1 million) and $31 100 (80% UI = 2100->1 million) with and without cross-protection, respectively. Results are robust to assumptions about HPV natural history, screening methods, duration of protection, and healthcare costs.
  
  
  CONCLUSIONS
  Switching to a 9-valent gender-neutral HPV vaccination program is likely to be cost-saving if the additional cost/dose of the 9-valent is less than $13. Giving females the 9-valent vaccine provides the majority of benefits of a gender-neutral strategy.
authors.affiliation: Centre de recherche du CHU de Québec, Axe Santé des populations et pratiques optimales en santé, Québec, Canada (MB, JFL, MD, TM); Département de médecine sociale et préventive, Université Laval, Québec, Canada (MB, MD, TM); Department of Infectious Disease Epidemiology, Imperial College, London, UK (MB, MCB); National Center for HIV, Viral Hepatitis, STD and TB Prevention, Centers for Disease Control and Prevention (CDC), Atlanta, GA (HWC, LEM). marc.brisson@crchudequebec.ulaval.ca.
authors.forename: Marc
authors.initials: M
authors.lastname: Brisson
authors.affiliation: Centre de recherche du CHU de Québec, Axe Santé des populations et pratiques optimales en santé, Québec, Canada (MB, JFL, MD, TM); Département de médecine sociale et préventive, Université Laval, Québec, Canada (MB, MD, TM); Department of Infectious Disease Epidemiology, Imperial College, London, UK (MB, MCB); National Center for HIV, Viral Hepatitis, STD and TB Prevention, Centers for Disease Control and Prevention (CDC), Atlanta, GA (HWC, LEM).
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Laprise
authors.affiliation: Centre de recherche du CHU de Québec, Axe Santé des populations et pratiques optimales en santé, Québec, Canada (MB, JFL, MD, TM); Département de médecine sociale et préventive, Université Laval, Québec, Canada (MB, MD, TM); Department of Infectious Disease Epidemiology, Imperial College, London, UK (MB, MCB); National Center for HIV, Viral Hepatitis, STD and TB Prevention, Centers for Disease Control and Prevention (CDC), Atlanta, GA (HWC, LEM).
authors.forename: Harrell W
authors.initials: HW
authors.lastname: Chesson
authors.affiliation: Centre de recherche du CHU de Québec, Axe Santé des populations et pratiques optimales en santé, Québec, Canada (MB, JFL, MD, TM); Département de médecine sociale et préventive, Université Laval, Québec, Canada (MB, MD, TM); Department of Infectious Disease Epidemiology, Imperial College, London, UK (MB, MCB); National Center for HIV, Viral Hepatitis, STD and TB Prevention, Centers for Disease Control and Prevention (CDC), Atlanta, GA (HWC, LEM).
authors.forename: Mélanie
authors.initials: M
authors.lastname: Drolet
authors.affiliation: Centre de recherche du CHU de Québec, Axe Santé des populations et pratiques optimales en santé, Québec, Canada (MB, JFL, MD, TM); Département de médecine sociale et préventive, Université Laval, Québec, Canada (MB, MD, TM); Department of Infectious Disease Epidemiology, Imperial College, London, UK (MB, MCB); National Center for HIV, Viral Hepatitis, STD and TB Prevention, Centers for Disease Control and Prevention (CDC), Atlanta, GA (HWC, LEM).
authors.forename: Talía
authors.initials: T
authors.lastname: Malagón
authors.affiliation: Centre de recherche du CHU de Québec, Axe Santé des populations et pratiques optimales en santé, Québec, Canada (MB, JFL, MD, TM); Département de médecine sociale et préventive, Université Laval, Québec, Canada (MB, MD, TM); Department of Infectious Disease Epidemiology, Imperial College, London, UK (MB, MCB); National Center for HIV, Viral Hepatitis, STD and TB Prevention, Centers for Disease Control and Prevention (CDC), Atlanta, GA (HWC, LEM).
authors.forename: Marie-Claude
authors.initials: MC
authors.lastname: Boily
authors.affiliation: Centre de recherche du CHU de Québec, Axe Santé des populations et pratiques optimales en santé, Québec, Canada (MB, JFL, MD, TM); Département de médecine sociale et préventive, Université Laval, Québec, Canada (MB, MD, TM); Department of Infectious Disease Epidemiology, Imperial College, London, UK (MB, MCB); National Center for HIV, Viral Hepatitis, STD and TB Prevention, Centers for Disease Control and Prevention (CDC), Atlanta, GA (HWC, LEM).
authors.forename: Lauri E
authors.initials: LE
authors.lastname: Markowitz
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D017046:Cost Savings; D003362:Cost-Benefit Analysis; D018562:Disease Transmission, Infectious / Q000517:prevention & control*; D005260:Female; D000068857:Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18 / Q000008:administration & dosage / Q000191:economics; D006801:Humans; D008297:Male; D032541:Mass Vaccination / Q000191:economics*; D015233:Models, Statistical; D009959:Oropharyngeal Neoplasms / Q000191:economics / Q000517:prevention & control* / Q000821:virology; D030361:Papillomavirus Infections / Q000150:complications / Q000191:economics* / Q000517:prevention & control* / Q000821:virology; D053918:Papillomavirus Vaccines / Q000008:administration & dosage* / Q000191:economics*; D019057:Quality-Adjusted Life Years; D012725:Sexual Behavior; D014481:United States; D002583:Uterine Cervical Neoplasms / Q000191:economics / Q000517:prevention & control* / Q000821:virology; D055815:Young Adult
chemical_list: D000068857:Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18; D053918:Papillomavirus Vaccines