Acambis first to test West Nile vacc in older adults

UK-headquartered Acambis says that clinical testing of its investigational West Nile virus vaccine, ChimeriVax-West Nile, is underway in older adults, those most in need of protection against this infection. Acambis' ChimeriVax-West Nile is the most advanced product in development for this condition and the first to be tested in older adults.

According to the US Centers for Disease Control and Prevention (CDC), people over the age of 50 are more likely to develop serious symptoms from West Nile virus infection; however, individuals of all ages living in areas where this virus has been identified are at risk. West Nile virus continues to be a high-profile problem in the USA, causing 4,256 cases and 165 deaths in 2006. This is a more than 41% increase in the number of cases and 38% increase in deaths compared with 2005, the drugmaker points out.

The trial is designed to evaluate the safety, tolerability and immunogenicity of ChimeriVax-West Nile in older adults and is being conducted in the USA. The randomized, double-blind, placebo-controlled study is the second part of a Phase II evaluation of the vaccine.