Tailor-made HIV/AIDS treatment closer to reality

By "priming" the immune system, as with a vaccine, to fight the specific strain of HIV/AIDS infecting a given patient, the scientists believe they have developed a therapy that shows immense promise and could be an even more effective weapon against the virus than the anti-retroviral cocktails currently in use. The results of the first-stage clinical trials, which tested the therapy in conjunction with anti-retroviral drugs, were published recently in Clinical Immunology. Phase 2 of the clinical trial, which is nearly complete, is testing the therapy's efficacy on its own at 8 different sites in Canada.

The new therapy uses dendritic cells which are removed from each HIV-infected patient and subsequently multiplied in-vitro. Dendritic cells present material from invading viruses on their surface, allowing the rest of the immune system to identify and attack the invaders. "They are the "grand conductors" of the immune response," explains Dr Routy. "With them, you push the immune system, in all its functions, at the same time." In the current trial, dendritic cells were exposed to a sample of HIV RNA (ribonucleic acid) specific to the patient involved. This exposure encouraged the cells to develop defences specific to that viral strain. The modified cells -- called AGS-004 -- were then injected back into the patients.

Not only were there few reported side-effects from the AGS-004, but the researchers also measured increased levels of CD8-lymphocytes in the patients -- the "attack" cells of the human immune system that the treatment is intended to mobilize, thus confirming that the intervention was targeted and controlled.

By boosting the immune system in this way, Routy hopes to develop an HIV/AIDS treatment that will require fewer injections and less long-term toxicity for patients than antriretrovirals.

Dr. Jean-Pierre Routy is a practitioner in the Division of Hematology at the MUHC as well as a researcher in the Infection and Immunity Axis at the Research Institute of the MUHC. He is also an Associate Professor of Hematology at McGill University in addition to a senior clinical researcher with the Fonds de la Recherche en Santé du Québec (FRSQ).

This study was funded by a grant from the Canadian Network for Vaccines and Immunotherapeutics (CANVAC), the Canadian HIV Trials Network (CTN), the National Institutes of Health (NIH) and Argos Therapeutics.

This article was co-authored by Rafick-Pierre Sékaly, Université de Montréal, Mohamed-Rachid Boulassel of the McGill University Health Centre (MUHC), Bader Yassine-Diab and Oleg Yegorov of the Université de Montréal and Centre Hospitalier de l'Université de Montréal (CHUM), Lothar Finke, Don Healey, Renu Jain, Tamara Monesmith ,Charles Nicolette and Irina Tcherepanova of Argos Therapeutics, In, Durham, USA.