GlaxoSmithKline's shingles vaccine shows positive results in adults 70 and older

Scientific data about Glaxo's shingles vaccine, Shingrix, was published this week in the New England Journal of Medicine coming out Thursday.  In adults age 70 and older, two doses of the vaccine demonstrated 90 percent efficacy compared with a placebo.  An earlier study in people age 50 and over showed the GSK vaccine was 97.2 percent effective compared with a placebo.

Currently, Merck has the only approved vaccine, Zostavax, for the herpes zoster (shingles) virus, which was approved in 2006.  The effectiveness of Merck's vaccine was found in a Kaiser Permanente study of adults 60 years and older to decrease from 68.7 percent effective initially to 4.2 percent in the eighth year after vaccination.

Study results published in the New England Journal found that the efficacy of the GSK vaccine went down slightly, from 90 percent to 88 percent, four years after people were vaccinated.

"Given the limited efficacy and duration of Zostavax, newer vaccine formulations with improved efficacy are welcome," a New England Journal editorial said.

Adults' immune systems to protect against diseases decline with age. Shingles, which usually occurs after 50, is related to the childhood illness chicken pox.

After the itchy blisters of chicken pox disappear, the varicella zoster virus goes dormant in nerve cells.  Years later, the virus can reactivate as shingles. People who live to 85 have a 50-50 chance of developing shingles, which can result in a complication called postherpetic neuralgia, a debilitating nerve pain.

Shingles typically shows up as a painful, itchy rash that develops on one side of the  body.

The Merck vaccine is made from a weakened form of the herpes zoster virus. In contrast, the Glaxo vaccine is made from a single viral protein combined with an immune-stimulating substance known as an adjuvant.

"This is the first time that such high efficacy has been demonstrated in a vaccine candidate for older people and it is remarkable, as we know that these people frequently have an age-related weakening of their immune system," said Emmanuel Hanon, GSK senior vice president of vaccines research and development.

Anthony Cunningham, executive director of the Westmead Institute for Medical Research in Australia and principal investigator of the latest study, said people over 70 and 80 years are "the age groups most affected by the disease."

"Importantly," the vaccine "also prevents a common and feared complication of herpes zoster -- prolonged pain, or post herpetic neuralgia in these groups," he said.

There are ongoing studies, both by GSK and an outside medical investigator, looking at whether people who have had the Zostavax vaccine could also get the Glaxo vaccine, if approved by the Food and Drug Administration.

GSK employs about 5,000 in the Philadelphia area, at the Navy Yard and at research and development sites in Upper Merion and Upper Providence in Montgomery County.