Interleukin-2 Plus Antiretroviral Therapy for HIV-Infected Patients With Low CD4+ Counts (SILCAAT Study)

Study Summary

This study will examine whether interleukin-2 (IL-2) plus antiretroviral therapy (ART) slows HIV disease progression in patients with low CD4+ T cell counts compared with patients taking ART alone. CD4+ T cells are a subset of lymphocytes-white blood cells that are part of the body's immune system. IL-2 is a protein that is naturally produced by lymphocytes. Given in intermittent cycles, IL-2 can raise CD4+ T cell counts in some HIV-infected patients taking antiretroviral drugs. This study will examine whether the increase in CD4+ T cells lowers the risk of AIDS-related illnesses and death. HIV-infected patients 18 years of age and older with a viral load under 10,000 copies per milliliter and a CD4+ T cell count between 50 and 299 cells per cubic millimeter who are taking antiretroviral therapy and who have not previously received IL-2 therapy may be eligible for this study. Candidates will be screened with a medical history, physical examination, and blood and urine tests. Participation in the study will be from 4.5 to 6 years, depending on what point in the duration of the study the individual patient is enrolled. Patients will be randomly assigned to receive IL-2 plus ART or ART alone. All participants will be advised individually about the best ART regimen for them. Patients in the IL-2 treatment group will be taught how to self-inject IL-2 under the skin (similar to insulin injections). They will inject IL-2 twice a day for 5 days every 8 weeks for the first year (until week 49 of the study). From week 49 on they may receive 5-day cycles of IL-2 every 4 months when needed to maintain CD4+ T cell count elevations. An extra cycle may be given 2 months after the week 49 follow-up visit (see follow-up schedule below), depending on their CD4+ T cell count. Patients whose cell counts have not increased after 12 to 16 months of IL-2 treatment will discuss with the doctor the possibility of stopping IL-2. Those who do stop IL-2 treatment will be asked to remain in t

Primary Outcome

Number of participants with fatal or non-fatal AIDS-related opportunistic disease or death from any cause. AIDS-related opportunistic disease includes CDC Category C 1993 definition plus the following diseases: Aspergillosis, invasive; Bartonellosis; Chagas disease of the CNS; Herpes zoster, multidermal; Leishmaniasis, visceral; Lymphoma, Hodgkin's; Microsporidiosis (\> 1 month's duration); Nocardiosis; Penicillium marneffti, disseminated; Pneumocystis carinii, extrapulmonary; Rhodococcus equi

Interventions

• DRUG Proleukin