US Food and Drug Administration (FDA) has approved the use of Zostavax, a live attenuated virus vaccine, for the prevention of shingles in individuals 50 to 59 years of age. Zostavax is already approved for use in individuals 60 years of age and older.
Shingles is a disease caused by the varicella-zoster virus, which is a virus in the herpes family and the same virus that causes chickenpox. After an attack of chickenpox, the virus lies dormant in certain nerves in the body. For reasons that are not fully understood, the virus can reappear in the form of shingles, more commonly in people with weakened immune systems and with aging.
“The likelihood of shingles increases with age. The availability of Zostavax to a younger age group provides an additional opportunity to prevent this often painful and debilitating disease,” said Dr Karen Midthun, director, FDA’s Centre for Biologics Evaluation and Research.
Shingles is characterized by a rash of blisters, which generally develop in a band on one side of the body and can cause severe pain that may last for weeks, and in some people, for months or years after the episode.
According to FDA, the approval was based on a multicentre study conducted in the US and four other countries in 22,000 people who were 50-59 years of age. Half received Zostavax and half received a placebo. The study participants were then monitored for at least one year to see if they developed shingles. Compared with placebo, Zostavax reduced the risk of developing shingles by 70 per cent.
The most common side effects observed in the study were redness, pain and swelling at the site of injection, and headache. Zostavax, which is manufactured by US-based Merck, was originally approved in May 2006, for the prevention of shingles in individuals 60 years of age and older.