Safety of and Immune Response to a West Nile Virus Vaccine (WN/DEN4delta30) in Healthy Adults

West Nile Fever Clinical Trial

Official title: Phase 1 Study of the Safety and Immunogenicity of a 2-Dose Regimen of West Nile/Dengue 4-3'delta30 Chimeric Virus Vaccine (WN/DEN4delta30), a Live Attenuated Vaccine for West Nile Encephalitis

Status Completed

Clinical Trial Summary

West Nile (WN) virus infection is an emerging disease. Infection with WN virus may lead to paralysis, coma, and death. The purpose of this study is to determine the safety of and immune response to a two-dose regimen of a WN vaccine in healthy adults. The vaccine is based on a live attenuated vaccine developed against dengue virus.

Clinical Trial Description

WN is widely distributed in Africa and Europe, where it is usually associated with mild illness. In the United States, WN is considered a public health threat because severe illness caused by WN infection has caused paralysis, coma, and death, especially in the elderly. This study will evaluate the safety and immunogenicity of a live attenuated chimeric virus, WN/DEN4delta30, which is derived from the DEN4 dengue virus and wild-type WN serotypes.

This study will last at least 32 weeks. Participants in Cohort 1 will be randomly assigned to receive 1X10^4 plaque-forming units (PFU) WN/DEN4delta30 or placebo at study entry and Day 180. Cohort 2 will be randomly assigned to receive a higher dose of WN/DEN4delta30, 10^5 PFU, or placebo at study entry and Day 180. Immediately after receiving their injections, participants will be observed for 30 minutes for immediate adverse reactions.

After each vaccination, participants will be asked to monitor their temperatures three times every day for 16 days. Study visits will occur every other day after each vaccination until Day 16, followed by three additional visits at selected days through Day 180 post-vaccination. Blood collection, medical history, vital signs measurement, and a targeted physical exam will occur at all visits. Participants will also be required to keep temperature diaries until Day 16 after vaccination. Female participants will have a urine pregnancy test performed within 60 days of study entry, and on Days 28, 42, 150, 180, 208, and 222. Pregnancy prevention counseling will occur at selected visits. ;

Study Design

Allocation: Randomized, Endpoint Classification: Safety Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator), Primary Purpose: Prevention

Related Conditions & MeSH terms

• West Nile Fever

• NCT number: NCT00537147
• Study type: Interventional
• Source: National Institute of Allergy and Infectious Diseases (NIAID)
• Status: Completed
• Phase: Phase 1
• Start date: March 2008
• Completion date: June 2009