Immune Responses to H5N1 Vaccine With and Without AS03 Adjuvant

Overview

Background: \- Adjuvants are substances included in vaccines that stimulate the immune system and increase the body's response to the vaccine. The AS03 adjuvant is used in seasonal flu vaccines in Europe. However, it has not been fully tested in the United States. Researchers want to test the immune responses of people who receive a bird flu vaccine with or without AS03 to better understand how the adjuvant works. This information may help develop better flu vaccines. Objectives: \- To compare the healthy immune system responses to bird flu vaccine with or without the AS03 adjuvant. Eligibility: \- Healthy volunteers between 18 and 45 years of age. Design: * Participants will be screened with a physical exam and medical history. * Participants will be assigned to one of two groups. Each group will have an initial vaccine, followed by a booster vaccine 21 days later. Both vaccinations will use the same type of vaccine. One group will have the vaccine with AS03; the other group will have the vaccine without it. * All participants will have two 36-hour inpatient stays to receive the vaccine. Each stay will involve the vaccination, followed by regular and frequent blood draws. Participants will be monitored for any signs or symptoms that may be caused by the vaccine. * Additional blood samples will be collected 7, 28, 42, and 100 days after the initial vaccination.

Adjuvants have been in use for many decades to enhance the effects of vaccines on the host immune system, yet we know very little on how they actually work. Better understanding of the mechanism by which adjuvants activate the immune system will enable us to develop better and safer vaccines as well as a broad range of immune interventions to a wide spectrum of diseases including cancer and autoimmunity. In the current study we propose to study the effect of AS03 adjuvant on the innate/early immune response to H5N1, avian flu, a potentially lethal disease that most subjects are assumed to be naive to AS03 is an adjuvant oil in water emulsion containing DL-alpha-tocopherol, squalene and the non-ionic detergent Tween 80 that has been widely used as an adjuvant to flu vaccines produced by GlaxoSmithKline(GSK). We therefore propose to randomize up to 60 healthy volunteers into two intervention arms (25 volunteers in each arm with up to 10 total replacements in the event a volunteer does not return for the first vaccine). The first arm will receive a vaccine containing H5N1 with AS03 adjuvant, the second arm will receive H5N1 without AS03 adjuvant. Both arms will receive primary and booster vaccination followed by repeated blood sampling to evaluate the immune responses. We will apply high throughput analytic techniques and use systems biology methods to integrate the collected data and draw a description of the immune system response with and without the adjuvant. The primary objective is to compare multiplex immune response signatures following two (primary and a boost) vaccinations with the GSK AS03 adjuvanted H5N1 influenza vaccine, or the non-adjuvanted form of the H5N1 influenza vaccine, at the 3.75 mcg dose and given 21 days apart and identify differences in very early innate immune responses. These immune signatures will also be correlated with the clinical observations especially safety related local and systemic events.