US FDA approves Merck & Co's Zostavax, the first medical prevention for shingles

The US Food and Drug Administration has approved Merck & Co's new vaccine Zostavax (live varicella zoster vaccine ) for prevention of herpes zoster in individuals 60 years of age and older. The condition, which is commonly known as shingles, is a frequently-painful disease marked by a blistering rash and caused by the reactivation of the virus that causes chickenpox.

New Jersey-headquartered Merck, which is the USA's largest pharmaceutical group after Pfizer, says the efficacy and safety of the agent as a single dose was evaluated in the landmark Shingles Prevention Study of 38,546 men and women age 60 and over who had no previous history of shingles. According to the firm, in the randomized, double-blind, placebo-controlled study of Zostavax significantly reduced the risk shingles 51% compared with placebo (p<0.001), adding that its efficacy in preventing the condition was highest for those between 60 to 69 years of age and declined with increasing age.

Industry observers have played down the direct importance of the approval, pointing out that, with peak annual sales of around $300.0 million, Zostavax will not make a significant contribution to Merck's revenue. By comparison, the firm's top-selling drug, the cholesterol-lowering product, Zocor (simvastatin), contributed first-quarter 2006 sales of $1.06 billion but will soon lose its patent protection.