Combination antiretroviral therapy including two nucleoside reverse transcriptase inhibitors (NRTIs) and a single HIV-1 protease inhibitor (PI) results in significant and sustained decreases in plasma HIV-1 RNA with a resultant marked diminution in the selection of drug-resistant variants in those able to adhere to and tolerate these regimens. However, two lines of evidence suggest that additional and perhaps more aggressive approaches may be necessary in some HIV-infected individuals: 1) the failure of some potent three-drug regimens to sustain viral replication to levels below the limits of detection; and 2) the ability to recover virus from lymphoid tissue obtained from those without evidence of detectable plasma HIV-1 RNA using the most sensitive assays. A regimen containing more drugs with potentially different mechanisms of action or synergistic activity may result in greater, more rapid, or more durable antiviral activity, or reduce the number of latently infected cells in those patients with acute or early HIV-1 infection.

Patients in Group I begin study therapy within 7 to 14 days of screening. Patients are randomized to 1 of 2 treatment arms. Arm A receives stavudine (d4T) plus didanosine (ddI) plus ritonavir plus indinavir. Arm B receives d4T plus ddI plus ritonavir plus indinavir plus hydroxyurea. Patients are discontinued from hydroxyurea after Week 24. Group II consists of patients who meet eligibility criteria but who elect not to receive antiretroviral treatment. Patients in Groups I and II follow the same schedule of evaluations. Enrollment visit (Week 0) evaluations are completed prior to dispensing drugs, and all patients have clinical, virologic, and immunologic evaluations performed every 4 weeks through Week 24, then every 8 weeks thereafter. Patients in Group I take study drugs for 104 weeks with an optional 52-week rollover. Laboratory results from the Week 96 evaluation are used to decide whether or not patients continue on study medications. Patients who elect not to participate in the optional rollover or meet criteria for treatment failure at any time during the study are offered the best available treatment at the discretion of their HIV care provider and continue to be followed at 8-week intervals.