The purpose of this study is to see if it is safe and effective to give combinations of three or four anti-HIV drugs to HIV-infected patients. The drugs used in this study are delavirdine (DLV), nelfinavir (NLF), didanosine (ddI), and stavudine (d4T).

This is a multicenter, open-label study. Patients are stratified by HIV-1 RNA levels (20,000 to 200,000 copies/ml and greater than 200,000 copies/ml). Patients are equally randomized to one of four groups and receive antiretroviral therapy for 24 weeks. Group 1 receives delavirdine (DLV) plus nelfinavir (NFV) plus stavudine (d4T). Group 2 receives DLV plus NFV plus didanosine (ddI). Group 3 receives NFV plus d4T plus ddI. Group 4 receives DLV plus NFV plus d4T plus ddI. Patients are evaluated for drug safety and viral burden. Patients may opt to continue on the study for 24 additional weeks, at the discretion of the investigator.

Inclusion Criteria

You may be eligible for this study if you:

• Are at least 18 years old.
• Are HIV-positive.
• Have a CD4 count of at least 50 cells/mm3.
• Have a viral load of at least 20,000 copies/ml.

Exclusion Criteria

You will not be eligible for this study if you:

• Have taken d4T.
• Have taken protease inhibitors, including NFV.
• Have taken nonnucleoside reverse transcriptase inhibitors.
• Have taken ddI for 1 month or more.