To examine the efficacy of saquinavir SGC (soft gel capsules) in combination with other antiretrovirals in HIV-1 infected patients currently treated with saquinavir HGC (hard gel capsules) measured by the absolute change in plasma HIV-1 RNA during the 24 weeks of study treatment.

Eligible patients will be stratified by HIV-1 RNA level into 2 populations: 1) >= 5,000-30,000 HIV-1 RNA, 2) > 30,000 HIV-1 RNA. All patients will be randomized to 1 of 3 treatment arms: Arm A - Saquinavir soft gel capsules (SQV SGC) + 2 new nucleoside analogs (reverse transcriptase inhibitors [RTIs]), Arm B - SQV SGC + nelfinavir + stavudine (d4T) or a new RTI, or Arm C - SQV SGC + ritonavir + d4T or a new RTI. All patients will undergo plasma HIV-1 RNA determinations, CD4 lymphocyte counts, hematology and chemistry blood work at baseline, weeks 4, 8, 12, 16 and 24.

Inclusion Criteria

Patients must have:

• Documented HIV infection.
• CD4 > 100 cells/mm3.
• Saquinavir HGC-experienced patients (>= 3 months cumulative therapy).

Required:

>= 3 months cumulative saquinavir HGC therapy.