About The Study

This clinical research study tested the efficacy and safety of AGS-004, an experimental immunotherapy, to control HIV replication during analytical treatment interruption. As a follow up study to CTN 229 and CTN 239, this study was designed to see if AGS-004 increases the body’s immune response to HIV and if, even after stopping ART, the immunotherapy can control HIV replication.

AGS-004 is created from a person’s own dendritic cells — white blood cells that stimulate the body’s immune system — and a sample of their HIV virus. This is the first experimental treatment designed from a person’s HIV genetic material and their body’s cells. This study was sponsored by Argos Therapeutics (Durham, NC), CIHR, and the NIH. For more information about this trial, see clinicaltrials.gov.

Study Approach

In this randomized, double-blind, phase 2B trial, researchers administered AGS-004 intradermally — into the skin — every four weeks while on ART. At week sixteen, participants underwent a clinically controlled ART interruption for twelve weeks while still receiving the injection every four weeks. Any study participant with a plasma HIV level >200 copies per mL or a CD4 count >450 cells per cubic mm at week fourteen did not undergo the treatment interruption. Plasma HIV levels and CD4 counts were monitored through the treatment interruption.


The immune response caused by AGS-004 was not effective in improving viral control compared with placebo, as measured during treatment interruption. Both the plasma HIV levels and changes in CD4 cell count were similar between placebo and treatment groups.


Although CTN 229 and 239 found that AGS-004 was safe and showed promising effects on the immune system, CTN 256 found that there was no antiviral effect compared to placebo.

Principal Investigators

Here’s who is leading this study.

Can’t find what you’re looking for? Email ctninfo@hivnet.ubc.ca.

Participating Sites

Here’s where this study is being conducted.