In a large clinical study of adults ages 50 to 59, ZOSTAVAXÂ® (Zoster Vaccine Live), Merck's vaccine for the prevention of shingles (herpes zoster), reduced the incidence of shingles by nearly 70 percent (69.8) compared to placebo.Â These new data were presented at the 48th annual meeting of the Infectious Diseases Society of America (IDSA) held last week in Vancouver.Â Based on these results, earlier this year Merck filed a supplemental Biologics License Application (sBLA) with the Food and Drug Administration (FDA) for the use of ZOSTAVAX to prevent shingles in people 50 to 59 years of age.
In this study, ZOSTAVAX significantly reduced the incidence of shingles in adults in their 50s when compared with placebo," says Myron Levin, MD, one of the studys investigators, and professor in the Departments of Pediatrics and Medicine at the University of Colorado School of Medicine's Division of Infectious Diseases and Department of Pediatrics, The Children's Hospital.
ZOSTAVAX is indicated for the prevention of herpes zoster (shingles) in people 60 years of age and older and is the only shingles vaccine licensed for use in the U.S.Â ZOSTAVAX is not indicated for the treatment of shingles or postherpetic neuralgia (PHN).Â The Centers for Disease Control and Prevention (CDC) recommends a single dose of ZOSTAVAX for all appropriate people 60 years of age and older, regardless of whether they have had a prior case of shingles.
This randomized, double-blind, placebo-controlled study included 22,439 adults aged 50 to 59 years; 11,211 volunteers received ZOSTAVAX and 11,228 received placebo. Participants also were followed for adverse events (AEs) for 42 days postvaccination and for serious adverse events (SAEs) through six months postvaccination. Â participants were monitored for occurrence of shingles for at least one year or longer after receiving vaccination.
The estimated geometric mean titer (GMT) ratio of 2.3 (95 percent CI: 2.2, 2.4; p<0.001) compared to placebo, which met the pre-specified success criterion for this endpoint. Â The vaccine induced a significantly higher varicella-zoster virus (VZV) antibody response, as measured by gpELISA, when compared to placebo at six weeks post-vaccination.Â efficacy of the vaccine was 69.8 percent (95 percent Confidence Interval (CI): 54.1 percent, 80.6 percent), which met the studys pre-specified criteria for success.Â In this study, 30 cases of shingles occurred in the vaccine group versus 99 cases of shingles in the placebo group:
An investigator-determined, vaccine-related SAE (anaphylactic reaction) was reported for one study participant who received ZOSTAVAX. Â With respect to SAEs, a similar proportion of subjects in both the vaccine and placebo groups reported SAEs within 42 days of vaccination (0.6 percent for vaccine vs. 0.5 percent for placebo) and 182 days of vaccination (2.1 percent for vaccine vs. 1.9 percent for placebo).Â There was also a significantly higher rate of systemic AEs in the aggregate (35.4 percent for vaccine vs. 33.5 percent for placebo); however, no significant differences were observed between the two study groups for any individual systemic AEs with the exception of pain in the extremity and headache.Â In this study, there was an overall higher incidence of AEs in the vaccine group versus the placebo group (72.8 percent for vaccine vs. 41.5 percent for placebo); this difference was primarily due to different rates of injection-site AEs (63.9 percent for vaccine vs. 14.4 percent for placebo). Â