The purpose of this study is to look at the safety and effectiveness of an experimental protease inhibitor (a type of anti-HIV drug) called BMS-232632. Doctors will compare an anti-HIV drug combination that includes BMS-232632 to a drug combination that includes ritonavir.

This is a three-arm study; patients are randomized to receive BMS-232632 at two different doses or RTV in combination with SQV and two nucleoside analogues over 48 weeks. Randomization is stratified for baseline phenotypic sensitivity.

Inclusion Criteria

Patients may be eligible for this study if they:

• Are HIV-positive.
• Have a viral load (level of HIV in the blood) of at least 2,000 copies/ml.
• Have a CD4 count of at least 100 cells/mm3 (or at least 75 cells/mm3 in patients who have never had an AIDS-defining illness).
• Are currently receiving an anti-HIV drug combination that includes a protease inhibitor or nonnucleoside reverse transcriptase inhibitor (NNRTI), and they have been taking this drug combination for at least 24 weeks. They must have responded well to this treatment at first (their viral load decreased) but are currently experiencing an increase in viral load.
• Will most likely respond well to the study drugs, as shown by the results of a lab test.
• Are at least 18 years old.
• Agree to use effective barrier methods of birth control (such as condoms).
• Are available for follow-up for at least 48 weeks.

Exclusion Criteria

Patients will not be eligible for this study if they:

• Have a newly diagnosed opportunistic (HIV-related) infection requiring treatment.
• Have only recently become HIV positive.
• Abuse alcohol or drugs.
• Have severe diarrhea within 30 days of study entry.
• Have hemophilia.
• Have a history of pancreatitis.
• Have hepatitis within 30 days of study entry.
• Have peripheral neuropathy (a painful condition affecting the nervous system).
• Are unable to take medications by mouth.
• Are pregnant or breast-feeding.