title: Long-term persistence of zoster vaccine efficacy.
abstract: BACKGROUND
  The Shingles Prevention Study (SPS) demonstrated zoster vaccine efficacy through 4 years postvaccination. A Short-Term Persistence Substudy (STPS) demonstrated persistence of vaccine efficacy for at least 5 years. A Long-Term Persistence Substudy (LTPS) was undertaken to further assess vaccine efficacy in SPS vaccine recipients followed for up to 11 years postvaccination. Study outcomes were assessed for the entire LTPS period and for each year from 7 to 11 years postvaccination.
  
  
  METHODS
  Surveillance, case determination, and follow-up were comparable to those in SPS and STPS. Because SPS placebo recipients were offered zoster vaccine before the LTPS began, there were no unvaccinated controls. Instead, SPS and STPS placebo results were used to model reference placebo groups.
  
  
  RESULTS
  The LTPS enrolled 6867 SPS vaccine recipients. Compared to SPS, estimated vaccine efficacy in LTPS decreased from 61.1% to 37.3% for the herpes zoster (HZ) burden of illness (BOI), from 66.5% to 35.4% for incidence of postherpetic neuralgia, and from 51.3% to 21.1% for incidence of HZ, and declined for all 3 outcome measures from 7 through 11 years postvaccination. Vaccine efficacy for the HZ BOI was significantly greater than zero through year 10 postvaccination, whereas vaccine efficacy for incidence of HZ was significantly greater than zero only through year 8.
  
  
  CONCLUSIONS
  Estimates of vaccine efficacy decreased over time in the LTPS population compared with modeled control estimates. Statistically significant vaccine efficacy for HZ BOI persisted into year 10 postvaccination, whereas statistically significant vaccine efficacy for incidence of HZ persisted only through year 8.
authors.affiliation: Veterans Affairs Medical Center and University of Minnesota, Minneapolis.
authors.forename: Vicki A
authors.initials: VA
authors.lastname: Morrison
authors.affiliation: Cooperative Studies Program Coordinating Center, Veterans Affairs Connecticut Healthcare System, West Haven.
authors.forename: Gary R
authors.initials: GR
authors.lastname: Johnson
authors.affiliation: Geriatric Research Education and Clinical Centers (GRECC), Durham Veterans Affairs Medical Center and Duke University, North Carolina.
authors.forename: Kenneth E
authors.initials: KE
authors.lastname: Schmader
authors.affiliation: University of Colorado Denver, Anschutz Medical Campus, Aurora.
authors.forename: Myron J
authors.initials: MJ
authors.lastname: Levin
authors.affiliation: Cooperative Studies Program Coordinating Center, Veterans Affairs Connecticut Healthcare System, West Haven.
authors.forename: Jane H
authors.initials: JH
authors.lastname: Zhang
authors.affiliation: Veterans Affairs San Diego Healthcare System and University of California, San Diego.
authors.forename: David J
authors.initials: DJ
authors.lastname: Looney
authors.affiliation: University of Rochester, New York.
authors.forename: Robert
authors.initials: R
authors.lastname: Betts
authors.affiliation: Veterans Affairs Medical Center, St Louis, Missouri.
authors.forename: Larry
authors.initials: L
authors.lastname: Gelb
authors.affiliation: Veterans Affairs San Diego Healthcare System and University of California, San Diego.
authors.forename: John C
authors.initials: JC
authors.lastname: Guatelli
authors.affiliation: Veterans Affairs San Diego Healthcare System and University of California, San Diego.
authors.forename: Ruth
authors.initials: R
authors.lastname: Harbecke
authors.affiliation: Hines Veterans Affairs Medical Center, Chicago, Illinois.
authors.forename: Connie
authors.initials: C
authors.lastname: Pachucki
authors.affiliation: Veterans Affairs Maryland Health Care System and University of Maryland, Baltimore.
authors.forename: Susan
authors.initials: S
authors.lastname: Keay
authors.affiliation: Veterans Affairs Medical Center, Seattle, Washington.
authors.forename: Barbara
authors.initials: B
authors.lastname: Menzies
authors.affiliation: Vanderbilt University and Mid-South GRECC, Veterans Affairs Tennessee Valley Healthcare System, Nashville.
authors.forename: Marie R
authors.initials: MR
authors.lastname: Griffin
authors.affiliation: Veterans Affairs Ann Arbor Health Care System and University Of Michigan, Ann Arbor.
authors.forename: Carol A
authors.initials: CA
authors.lastname: Kauffman
authors.affiliation: National Institute of Allergy and Infectious Diseases, Bethesda, Maryland.
authors.forename: Adriana
authors.initials: A
authors.lastname: Marques
authors.affiliation: Veterans Affairs Medical Center, Tampa, Florida.
authors.forename: John
authors.initials: J
authors.lastname: Toney
authors.affiliation: Cooperative Studies Program Central Research Pharmacy Coordinating Center, Albuquerque, New Mexico.
authors.forename: Kathy
authors.initials: K
authors.lastname: Boardman
authors.affiliation: Merck and Co, Whitehouse Station, New Jersey.
authors.forename: Shu-Chih
authors.initials: SC
authors.lastname: Su
authors.affiliation: Merck and Co, Whitehouse Station, New Jersey.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Li
authors.affiliation: Merck and Co, Whitehouse Station, New Jersey.
authors.forename: Ivan S F
authors.initials: IS
authors.lastname: Chan
authors.affiliation: Merck and Co, Whitehouse Station, New Jersey.
authors.forename: Janie
authors.initials: J
authors.lastname: Parrino
authors.affiliation: Merck and Co, Whitehouse Station, New Jersey.
authors.forename: Paula
authors.initials: P
authors.lastname: Annunziato
authors.affiliation: Veterans Affairs San Diego Healthcare System and University of California, San Diego.
authors.forename: Michael N
authors.initials: MN
authors.lastname: Oxman
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017281:Cost of Illness; D062665:Epidemiological Monitoring; D005260:Female; D005500:Follow-Up Studies; D006562:Herpes Zoster / Q000150:complications / Q000453:epidemiology / Q000517:prevention & control*; D053061:Herpes Zoster Vaccine / Q000009:adverse effects / Q000276:immunology; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D051474:Neuralgia, Postherpetic / Q000453:epidemiology / Q000517:prevention & control; D014611:Vaccination; D064166:Vaccine Potency
chemical_list: D053061:Herpes Zoster Vaccine
keywords: herpes zoster; herpes zoster burden of illness; herpes zoster vaccine; persistence of vaccine efficacy; postherpetic neuralgia