*Background: During chronic HIV-1 infection the immune system is chronically hyperactivated. This hyperactivation is considered as the main cause of CD4+ T-cell loss. Furthermore, HIV replicates most efficiently in activated CD4+ T-cells. In this study we try to inhibit the activation of the immune system with mycophenolate mofetil (MMF). Previous studies in which HIV-1 infected patients have been treated with MMF in addition to antiretroviral treatment (ART) have not shown any additional effect, compared to ART alone. In this study MMF will be used without antiretroviral medication.