Conditions: HIV Infection
Keywords: HIV infection T cell activation Antiretroviral Therapy CCR5 Maraviroc
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 45
Healthy volunteers: no

Brief summary:
Many people with HIV fail to regain normal CD4 counts despite effectively suppressing HIV replication with medications. Blocking the "co-receptor" for HIV might decrease inflammation of the immune system, potentially providing an immune benefit. The goal of the current trial is to determine whether adding maraviroc, a new CCR5 "co-receptor" blocker, decreases inflammation, providing an immune benefit for patients with low CD4 counts despite undetectable viral loads on HIV medications.

In this study, HIV-infected patients who are receiving antiretroviral therapy for HIV will receive either maraviroc or a placebo (sugar pill) each day for 24 weeks. After 24 weeks, the study medication will be stopped and all subjects will be followed for 12 more weeks. Blood tests measuring the extent of inflammation, low-level viremia, and immune function will be measured throughout the trial and compared between treatment arms.

Detailed description:
Our primary hypothesis is that CCR5 inhibitors may have protective immunomodulatory effects independent of their impact on HIV replication. Specifically, we predict that maraviroc will reduce the persistent T cell activation that prevents normal immune reconstitution during HAART-mediated viral suppression. This hypothesis will be tested in the context of a placebo controlled pilot study assessing the impact of maraviroc in antiretroviral-treated patients with a CD4+ T cell count less than 350 cells/mm3. In order to address the immunologic activity of this drug independent of plasma HIV RNA levels, we will study individuals who have undetectable viral loads (\< 75 copies RNA/mL). Subjects will be randomized to maraviroc for 24 weeks or matching placebo for 24 weeks, followed by a 12 week washout period. We will use as our primary endpoint the proportion of CD8+ T cells that co-expresses CD38 and HLA-DR, as these outcomes have been well validated in prior studies. The primary outcome will be change in the percentage of activated CD8+ T cells at week 24. Change in CD4+ T cell counts, HIV RNA levels (using ultra-sensitive techniques), and other more experimental immunologic measurements will be assessed as secondary outcomes.

Arms:
arm 1: Maraviroc (dose based on current medications in regimen: 150mg orally (PO) twice daily (BID) for those on a protease inhibitor-based regimen other than Tipranavir; 600mg PO BID for efavirenz-containing regimens; or 300 mg PO BID for all other regimens). arm 2: Placebo (dose based on current medications in regimen: 150mg PO BID for those on a protease inhibitor-based regimen other than Tipranavir; 600mg PO BID for efavirenz-containing regimens; or 300 mg PO BID for all other regimens).

Interventions: intervention 1: Placebo intervention 2: Maraviroc
Intervention descriptions: intervention 1: Dose based on current medications in regimen: 150mg PO BID for those on a protease inhibitor-based regimen other than Tipranavir; 600mg PO BID for efavirenz-containing regimens; or 300 mg PO BID for all other regimens. intervention 2: Dose based on current medications in regimen: 150mg orally (PO) twice daily (BID) for those on a protease inhibitor-based regimen other than Tipranavir; 600mg PO BID for efavirenz-containing regimens; or 300 mg PO BID for all other regimens.

Protocol document: