March 26, 2012 (San Diego, California) — Healthy adults 60 years and older get no added benefit from a second vaccination against varicella zoster virus (VZV), which suggests that those who have had shingles might also not benefit from subsequent vaccination, according to a report presented here at the American Academy of Dermatology (AAD) 70th Annual Meeting.
However, a zoster booster "might be worthwhile in individuals with a depressed immune system," said Rana Mays, MD, from the Center for Clinical Studies in Webster, Texas. She quickly added that this has not been studied.
Dr. Mays and her colleagues conducted a double-blind, placebo-controlled, multicenter study, in which they randomized 209 adults 60 years or older with a history of chicken pox to 2 doses of either the VZV vaccine (n = 104) or placebo (n = 105), given 42 days apart.
Immunogenicity was evaluated using a VZV interferon-gamma enzyme-linked immunospot (ELISPOT) assay and a VZV glycoprotein enzyme-linked immunosorbent antibody (gpELISA) assay.
The researchers found that immunogenicity increased significantly from baseline after the first vaccine, but there was no statistically significant increase after the second vaccine.
Specifically, VZV interferon-gamma ELISPOT geometric mean count of spot-forming cells per 106 peripheral blood mononuclear cells increased in the VZV group from 16.9 at baseline to 49.5 at 2 weeks and 32.8 at 6 weeks. After the second dose, the count at 2 weeks, 6 weeks, and 6 months was not significantly different, at 44.3, 42.9, and 36.5, respectively.
Overall, the findings show a slow decline in immunogenicity over the 6-month period, noted Dr. Mays.
As expected, immunogenicity did not increase in the placebo group.
There were no serious adverse effects in the vaccinated group, although 2 subjects discontinued because of injection-site reaction, vomiting, and vertigo, said Dr. Mays.
Dr. Mays was asked whether the recent approval by the US Food and Drug Administration of the VZV vaccine for adults 50 to 59 years of age (an extension of the previous age of 60 years and older), might make a booster shot necessary down the road, but she said that remains undetermined.
"Despite the wide use of the zoster vax, many patients do get surprised when they get shingles after vaccination, because the vaccine is not 100% effective; in fact, it is far short of that," said Richard L. Gallo, MD, PhD, professor and chief of dermatology at the University of California at San Diego. Even after vaccination, people have a 30% risk for infection, he told Medscape Medical News.
"If there was a strategy that could increase the effectiveness of the vaccine, that would be very useful. Unfortunately, this study did not show that. I am not sure we know definitively that there is no point to revaccination, but in terms of this study, we didn't see a big boost in their antibody titer."
Dr. Mays has disclosed no relevant financial relationships. Dr. Gallo reports receiving consulting fees from Allergan and Novartis; receiving investigator grants from Colgate-Palmolive, Galderma Laboratories, L.P., Intendis, Johnson & Johnson Consumer Product, and L'Oreal USA; and being a founder and stockholder of Skin Epibiotics.
American Academy of Dermatology (AAD) 70th Annual Meeting: Late-breaking abstract. Presented March 16, 2012.
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Cite this: No Benefit to Zoster Booster Vaccine - Medscape - Mar 26, 2012.
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