Since AZT has no effect on cells that contain inactive virus (latently infected cells) and these cells may act as viral reservoirs, that a second agent that can destroy these infected cells would be useful in combination with AZT. The different activities of AZT and IL-2, as well as the non-overlapping nature of their mechanisms of action and toxicity, increase the theoretical benefits of combining AZT, a drug which has clinically significant activity in HIV-related disease but cannot eliminate infected cells, with IL-2, a drug which may enhance anti-HIV immunity, destroy chronically infected cells, and allow immune recognition of latently infected cells.

Five patients who have already received and tolerated oral AZT for at least 8 weeks continue their AZT treatment and at the same time receive IL-2 on a schedule of 5 days on the drug, 2 days off the drug. The IL-2 is administered by 30-minute intravenous (IV) infusion according to this schedule for 4 weeks. The first week of IL-2 treatment is on an inpatient basis and the remaining 3 weeks are on an outpatient basis. Toxicity is monitored every week. Maximum tolerated dose (MTD) is defined as the maximum dose at which 3 out of 5 patients experience Grade 3 or above toxicity during the course of IL-2 administration. A second cohort of five patients will receive IV IL-2. If the MTD is not reached, five additional patients will receive IV IL-2. All five patients in a given cohort must complete a full 4-week course of IL-2 before subsequent patients are entered at the next higher dose level. After IV dosing is completed at these three levels, additional 5-patient cohorts receive subcutaneous (SC) IL-2 according to the same schedule. Each patient is restricted to one dosage group. Patients are treated and followed for a total of 24 weeks. Patients receive ibuprofen for fever and chills.