With about 1 million individuals getting herpes zoster each year in the United States, the best protection against the virus is vaccination.
The Centers for Disease Control and Prevention (CDC) recently released recommendations made by the Advisory Committee on Immunization Practices (ACIP) for the use of herpes zoster (shingles) vaccines.
About 1 million individuals are infected with herpes zoster each year in the United States and the best protection against the virus remains vaccination. With the US Food and Drug Administration’s (FDA) approval of GlaxoSmithKline’s Shingrix on October 20, 2017, there are now 2 vaccines against the virus available on the market.
Shingrix, the Zoster Vaccine Recombinant, Adjuvanted (RZV), is a 2-dose, subunit vaccine containing recombinant glycoprotein E in combination with a novel adjuvant, AS01B. The other vaccine, Merck’s Zostavax, or Zoster Vaccine Live (ZVL) was approved in 2006.
To create their recommendations, ACIP members reviewed data pertaining to the effectiveness of each vaccine in providing protection against herpes zoster as well as each vaccine’s cost-effectiveness. The recommendations were published in the CDC’s Morbidity and Mortality Weekly Report.
The effectiveness of RZV in preventing herpes zoster was assessed in a 2-part, phase 3 multicenter clinical trial which included over 30,000 participants randomized into 2 arms: those receiving the vaccine and those receiving placebo. The median follow-up time was 3.2 years for those participants who were 50 or older, and 3.7 years for those participants who were 70 or older. Investigators found that the vaccine was 96.6% effective in individuals between the ages of 50 and 59, 97.4% effective in those aged 60 to 69, and 91.3% effective in those 70 or older. Furthermore, vaccine efficacy in the first year after vaccination was 97.6% and 84.7% or higher 3 years after vaccination in those 70 or older.
Two randomized clinical trials and 7 observational studies evaluated the effectiveness of ZVL in preventing herpes zoster infections. A randomized clinical trial that enrolled individuals between 50 and 59 years of age found the vaccine to be 70% effective, while another randomized trial found the vaccine to be 64% effective in those aged 60 and older, and 38% effective in those aged 70 or older. The authors noted a “substantial decrease” in effectiveness following the first year post-vaccination. By 6 years post-vaccination, vaccines effectiveness falls to less than <35%.
In terms of cost-effectiveness, a CDC analysis conducted from a societal perspective over a lifetime found that “under most assumptions, vaccination with RZV prevented more disease at lower overall costs than did vaccination with ZVL,” the authors write. More information on the cost per quality-adjusted life year (QALY) is available in the study.
Taking into consideration available information, ACIP members approved the following recommendations at the October 2017 meeting:
Some additional important takeaways from the report include:
Finally, adults with a history of herpes zoster should still receive RZV; however, not while experiencing an episode. Those with chronic medical conditions such as chronic renal failure and diabetes mellitus, those taking low-dose immunosuppressive therapy and those anticipating immunosuppression or who have recovered from an immunocompromising illness should also receive RZV. Those with a history of severe allergic reaction should not receive RZV.
As more data become available, ACIP will review and revise recommendations accordingly.