CD4 count is the best predictor of HIV disease progression. IL-7 plays an important role in immune system function, especially in the development of T cells, including CD4 cells. IL-7 may improve HIV-specific immune responses by increasing the number of CD4 cells and boosting immune response. This study will evaluate the safety of a single IL-7 dose given under the skin in HIV infected patients who are currently on potent antiretroviral therapy (ART).~This study will last 13 weeks. Participants will be stratified into two groups by viral load: Stratum 1 participants will have viral loads of less than 50 copies/ml, and Stratum 2 participants will have viral loads between 50 and 50,000 copies/ml. Participants will receive one dose of either IL-7 or placebo at study entry. Five different dosing levels of IL-7 will be tested sequentially in both strata. Dose escalation will occur independently in each stratum and enrollment in a stratum will end when the maximum-tolerated dose is reached. As of 10/23/06, due to adverse events associated with the 60 mcg/kg dose level, all participants will receive up to the 30 mcg/kg dose level, with no further dose escalation. New participants will enroll in Stratum 2 only.~There will be 9 study visits; medical and medication history, a physical exam, lymph node and spleen assessment, and blood collection will occur at most visits. Participants will undergo an electrocardiogram at study entry and on Day 1, and a spleen ultrasound at Week 3. Urine collection will occur on Day 4 and at Weeks 2 and 3.
The purpose of this study is to determine the safety of a single, under-the-skin dose of interleukin-7 (IL-7) in HIV infected people currently taking anti-HIV drugs.