Inclusion Criteria

Patients must have:

• HIV infection documented by a licensed antibody ELISA assay and confirmed by Western blot, positive HIV blood culture, positive HIV serum antigen, or plasma viremia.
• CD4+ cell count of at least 300 cells/mm3.
• HIV-1 RNA less than 10,000 copies/ml by Roche Amplicor PCR assay.
• CDC Category A or B Classification for HIV infection (no clinical diagnosis of AIDS).
• Compliance with dosing schedule and protocol evaluations.

Prior Medication:

Required:

• 3TC at 150 mg bid, ZDV at 600 mg/day (200 mg tid or 300 mg bid), plus a marketed protease inhibitor (ritonavir, saquinavir, indinavir, or nelfinavir) at its recommended dose for at least 10 weeks.

Allowed:

• Inhaled corticosteroids for the treatment of asthma.

Exclusion Criteria

Co-existing Condition:

Patients with the following conditions or symptoms are excluded:

• Malabsorption syndromes affecting drug absorption (e.g., Crohn's disease and chronic pancreatitis).
• Enrollment in other investigational protocols.

Concurrent Medication:

Excluded:

• Cytotoxic chemotherapeutic agents.
• Nonnucleoside reverse transcriptase inhibitors.
• Other investigational agents.

Concurrent Treatment:

Excluded:

Radiation therapy.

Prior Medication:

Excluded:

• Cytotoxic chemotherapeutic and immunomodulating agents such as systemic corticosteroids, IF-2, alpha-IFN, beta-IFN, or gamma-IFN (except for inhaled corticosteroids for the treatment of asthma) within 4 weeks of study entry.
• HIV immunotherapeutic vaccine within 3 months of study entry.

Prior Treatment:

Excluded:

Radiation therapy within 4 weeks of study entry.