Revaccination With Subunit Influenza A/Vietnam/1203/2004 (H5N1) Vaccine
The purpose of this study is to determine whether having received an H5 vaccine in the past primes the immune system to respond rapidly to another dose of H5 vaccine. One hundred seventeen participants in a previous vaccine study (involving the A/Hong/Kong/97 virus) during the fall of 1998 at the University of Rochester will be eligible to enroll in this study. Participation in this study will up to 64 days and will involve donation of small samples of blood 7, 28, and 56 days after vaccination.
Biological: Influenza A/Vietnam/1203/2004 (H5N1; sanofi pasteur)
|Study Design:||Allocation: Non-Randomized
Endpoint Classification: Safety Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Prevention
|Official Title:||Revaccination of Healthy Subjects With Intramuscular Inactivated Subunit Influenza A/Vietnam/1203/2004 (H5N1) Vaccine Representing a Drifted Variant|
|Study Start Date:||October 2005|
|Estimated Study Completion Date:||March 2006|
|Primary Completion Date:||March 2006 (Final data collection date for primary outcome measure)|
This is an open label, phase I evaluation of a single dose of an investigational inactivated, subunit influenza A/Vietnam/1203/2004 (H5N1) vaccine in subjects who were previously vaccinated with a vaccine made from an antigenically distinct variant of H5N1. The study is designed to determine whether immunization with an antigenic variant can prime for responses to a single dose of vaccine representing the current pandemic threat. The primary objective is to determine the ability of a priming dose of rec H5 HA 1997 vaccine administered 7 years previously to result in booster responses to an inactivated subunit influenza A/Vietnam/1203/2004 (H5N1) vaccine. The secondary objectives are to 1) determine the safety of a booster dose of intramuscular inactivated subunit influenza A/Vietnam/1203/2004 (H5N1) vaccine in healthy adults, previously vaccinated with rec H5 HA 1997 vaccine and 2) evaluate the relationship between priming, levels of antigen-specific memory B and T cells , and the response to reactivation. The study will be performed at a single site, and will enroll as many previously vaccinated subjects as are available and eligible, up to a maximum of 117. Subjects will receive a single intramuscular dose of 90 mcg of the inactivated subunit influenza A/Vietnam/1203/2004 (H5N1) vaccine. Blood for assessment of antibody responses will be obtained before and at time points after vaccination. Subjects participating in the optional sub study will also have blood obtained for enumeration of memory B and T cells. Subjects will be followed for solicited adverse events for 7 days by memory aids and for 56 days for unsolicited adverse events. This study is linked to DMID protocol 08-0059.
|United States, New York|
|University of Rochester|
|Rochester, New York, United States, 14642|