Background. Herpes zoster (HZ) and postherpetic neuralgia (PHN) cause significant morbidity in older adults. The incidence and severity of HZ and PHN increase with age in association with an age-related decline in varicella-zoster virus (VZV)-specific cell-mediated immunity (VZV-CMI). VZV vaccines can boost VZV-CMI. Therefore, we tested the hypothesis that VZV vaccination would protect older adults against HZ and PHN. Methods. We enrolled 38,546 adults ≥60 years of age in a randomized, double-blind, placebo-controlled trial of an investigational HZ vaccine and actively followed subjects for the development of HZ. The primary end point was the burden of illness due to HZ (HZ BOI), a composite measure of the incidence, severity, and duration of pain and discomfort caused by HZ. The secondary end point was the incidence of PHN. Results. Subject retention was >95%. HZ vaccine reduced the HZ BOI by 61.1% (95% confidence interval [CI], 51.1%-69.1%; P < .001) and reduced the incidence of PHN by 66.5% (95% CI, 47.5%-79.2%; P < .001). The incidence of HZ was also reduced by 51.3% (95% CI, 44.2%-57.6%; P < .001). HZ vaccine was well tolerated; injection site reactions were generally mild. HZ vaccine neither caused nor induced HZ. Conclusion. The Shingles Prevention Study demonstrated that HZ vaccine significantly reduced the morbidity due to HZ and PHN in older adults.
Bibliographical noteFunding Information:
Supplement sponsorship. This article was published as part of a supplement entitled “Varicella Vaccine in the United States: A Decade of Prevention and the Way Forward,” sponsored by the Research Foundation for Microbial Diseases of Osaka University, GlaxoSmithKline Biologicals, the Sabin Vaccine Institute, the Centers for Disease Control and Prevention, and the March of Dimes.
Financial support: The Shingles Prevention Study, VA Cooperative Study #403, was conducted by the Cooperative Studies Program, Department of Veterans Affairs, Office of Research and Development in collaboration with the National Institute of Allergy and Infectious Diseases and Merck. Additional support was provided by a grant from Merck to the VA Cooperative Studies Program and by the James R. and Jesse V. Scott Fund for Shingles Research. Supplement sponsorship is detailed in the Acknowledgments.
Administrative and statistical support was provided by the VA Cooperative Studies Program Coordinating Center, West Haven, Connecticut: P. Antonelli, B. Huff, J. H. Zhang, T. C. Kyriakides, K. Newvine, R. Concepcion, K. DiBenedetto, S. O’Neil, and P. O’Brien.
Potential conflicts of interest: M.N.O. is Study Chairman of Department of Veterans Affairs (VA) Cooperative Study #403, The Shingles Prevention Study, and its substudies, which have been supported, in part, by grants from Merck to the VA Cooperative Studies Program, The VA San Diego Medical Research Foundation, and the VA Connecticut Research and Education Foundation. M.J.L. has received lecture fees and honoraria, consultation fees, and research support from Merck; holds a partial interest in a patent related to the herpes zoster vaccine; and is on the Merck speakers’ bureau.