In a double blind trial published this week in PLoS Medicine Rajesh Gandhi and colleagues detect no significant reduction in viral load after people with low-level HIV viremia had an integrase inhibitor added to their treatment regimen.
Antiretroviral therapy (ART) consists of combinations of drugs that prevent viral replication by inhibiting essential viral enzymes such as reverse transcriptase and protease. However, despite ART, residual viremia (virus in the blood) still occurs in HIV-positive individuals. The origin of this low-level residual viremia, and whether intensification of treatment can affect it, is controversial.
In this randomized, controlled trial the researchers assessed whether the addition of raltegravir (a drug that inhibits HIV integrase) to standard ART had any effect on residual viremia. The researchers found that the addition of raltegravir to ART for 12 weeks did not demonstrably reduce low-level residual viremia in HIV-positive individuals receiving standard ART. These findings suggest that residual viremia might be due to the release of HIV from stable reservoirs. If so, new therapeutic strategies designed to eliminate these reservoirs of latently infected cells will be required to cure HIV infection.
Gandhi RT, Zheng L, Bosch RJ, Chan ES, Margolis DM, et al. (2010) The Effect of Raltegravir Intensification on Low-level Residual Viremiain HIV-Infected Patients on Antiretroviral Therapy: A Randomized Controlled Trial. PLoS Med 7 (8): e1000321. doi:10.1371/journal.pmed.1000321