An open label study will be performed on 80 people with HIV infection who are maintained on effective treatment with antiretroviral drugs.

The goal of this study is to test whether a bowel anti-inflammatory drug that is known to be safe and effective for inflammatory bowel disease would offer benefit in reducing the residual immune activation associated with treated HIV-1 infection. Specifically, the two immediate goals are to examine the safety of Pentasa® in reducing markers of immune activation believed to be important reflectors of risk for cardiovascular disease and ongoing immune damage in people with chronic treated HIV-1 infection.

Inclusion Criteria:

• Age at least 18
• On ART for at least 1 year during which: viremia <50 RNA copies/ml for at least 3 measurements (allowing for 1 nonconsecutive blip of <100), and CD4 T cell count consistently >500 during that time
• CD4 T cell nadir >350
• Last CD4 and T cell test in past 6 months

Exclusion Criteria:

• Plans to modify antiretroviral therapy in the next 12 weeks for any reason
• History of inflammatory bowel disease or irritable bowel disease
• Chronic active hepatitis B or C
• History of autoimmune disease
• Hypersensitivity to any component of Pentasa
• Clostridium difficile infection
• Receiving rectally delivered medications
• Receiving anti-inflammatory medications (such as nonsteroidal anti- inflammatory drugs, steroids, or TNF inhibitors)
• Receiving immunosuppressive steroids
• Receiving any medications associated with bleeding risk
• Hemoglobin < 10.0 g/dL
• Platelet count less than 100,000/mm3
• White blood cell count < 2,000 cells/mm3 or > 15,000 cells/mm3
• Symptoms of sexually transmitted infection
• Antibiotics used in the last 90 days
• Renal insufficiency with creatinine clearance less than 50 ml/min
• Elevated transaminases greater than 2.5 times the upper limit of normal
• Evidence of decompensated cirrhosis, heart failure
• Pregnant or breastfeeding women