West Nile Virus Vaccine Enters Human Clinical Trials

A new investigational vaccine against West Nile Virus infection is now being tested in a Phase 1 clinical trial at Duke University.

West Nile Virus (WNV) isost commonly spread through the bite of infected mosquitoes. In the United States, the infection is usually a seasonal epidemic, beginning in late spring or early summer and continuing into the fall. Last year, 2,205 cases of WNV disease and 97 related deaths were reported in the United States.

Most individulas infected with WNV show no symptoms.

Roughly 1 in 5 people who are infected will display relatively mild symptoms, such as fever, headache, body aches, nausea, and vomiting. Only about 1 in 150 people infected with WNV will develop a serious neurologic illness, such as encephalitis or meningitis.

Most people with WNV disease make a complete recovery. Elderly and other immunocompromised individuals, however, are at higher risk for long-term side effects or death resulting from infection.

From 1999 to 2014, a total of 41,762 cases of WNV disease have been confirmed in the United States, including 1,765 deaths. Although an effective veterinary vaccine against WNV is available, no human vaccine has been approved for commercial use.

The experimental vaccine was discovered and developed by scientists at the Oregon National Primate Research Center at Oregon Health & Science University (OHSU) in Portland. The investigational vaccine, called HydroVax-001, was made with a unique, hydrogen peroxide-based process that renders the virus inactive while still maintaining key immune-system triggering surface structures.

The virus used to make the vaccine is inactivated and cannot cause WNV infection. Due to it’s inactivation, the experimental vaccine could likely be used in a diverse population, including immunologically vulnerable groups, such as the elderly.

The clinical trial, which will explore the safety of the vaccine and its ability to produce an immune response, will enroll 50 healthy men and women, ages 18 to 50 years. Volunteers are to be randomly assigned to receive a low dose of the vaccine (one microgram), a higher dose (four micrograms), or a placebo.

The study participants will be followed for 14 months.