Study of Autologous T-cells Genetically Modified at the CCR5 Gene by Zinc Finger Nucleases in HIV-Infected Subjects

Overview

This research study is being carried out to study a new way to possibly treat human immunodeficiency virus (HIV). The agent is called SB-728-T which are CD4+ T-cells obtained from an individual that are genetically modified at the CCR5 gene by Zinc Finger Nucleases. The CCR5 gene is required for certain types of HIV to enter into and infect T-cells. T cells are one of the white blood cells used by the body to fight HIV. The most important of these are called "CD4+ T-cells" Some people are born without the CCR5 gene on their T-Cells. These people remain healthy and are resistant to infection with HIV. Other people have a low number of CCR5 genes on their T-cells and their HIV disease is less severe and is slower to cause disease (AIDS). The purpose of this research study is to find out whether SB-728-T is safe to give to humans and find out how this affects HIV.

Laboratory studies have shown that when CD4+ T-cells are modified with Zinc Finger Nucleases SB-728, HIV is prevented from killing the CD4+ T-cells. On the basis of these laboratory results, there is the potential that this may work in humans infected with HIV and improve their immune system by allowing their CD4+ T-cells to survive longer. The new treatment to be studied will involve removing white blood cells from the blood that contain CD4+ T-cells. The extracted CD4+ T-cells are then genetically modified by the Zinc finger Nucleases to be resistant to infection by removing the CCR5 gene from the surface of the CD4+ T-cell where HIV enters the cell. Additional genetically modified cells are manufactured and then re-infused back into the individual. Researchers hope that these genetically modified cells will be resistant to infection by HIV and will be able to reproduce additional resistant CD4+ T-cells in your body.