The purpose of this study is to see if 141W94 is as safe and effective as indinavir when used with nucleoside reverse transcriptase inhibitors (NRTIs) for 48 weeks. This study also examines what effect other drugs have on how the body handles 141W94.

• Drug: Indinavir sulfate
• Drug: Amprenavir

Inclusion Criteria

Patients must have:

• Documented HIV infection.
• HIV RNA >= 400 copies/ml within 14 days prior to randomized study drug administration.
• No active AIDS-defining opportunistic infection or disease.
• Signed, informed consent from parent or legal guardian of patients less than 18 years of age.

Exclusion Criteria

Co-existing Condition:

Patients with the following conditions or symptoms are excluded:

• Unlikely to complete the randomized dosing period.
• Malabsorption syndrome or other gastrointestinal dysfunction that might interfere with drug absorption or ability to take oral medications.
• Serious medical conditions (e.g., diabetes, cardiac dysfunction, hepatitis) that would compromise patient safety.

Concurrent Medication:

Excluded:

• Cytotoxic chemotherapeutic agents (except local treatment for Kaposi's sarcoma).
• Investigational treatments (treatment through Treatment IND or expanded-access programs are evaluated individually).
• Immunomodulating agents such as systemic, high-dose corticosteroids, interleukins, or interferons.
• Terfenadine, astemizole, cisapride, triazolam, midazolam, and ergotamine/dihydroergotamine-containing regimens.

Concurrent Treatment:

Excluded:

Radiation therapy (except local treatment for Kaposi's sarcoma).

Patients with the following prior conditions are excluded:

Clinically relevant pancreatitis or hepatitis within the last 6 months.

Prior Medication:

Excluded:

• Cytotoxic chemotherapeutic agents within 30 days of study drug administration (except local treatment for Kaposi's sarcoma).
• Protease inhibitor therapy.
• Dose of vaccine through an investigational HIV vaccine trial within the 3 months prior to study drug administration.
• Immunomodulating agents such as systemic, high-dose corticosteroids, interleukins, or interferons within 30 days of study drug administration.

Prior Treatment:

Excluded:

Radiation therapy within 30 days prior to study drug administration (except local treatment for Kaposi's sarcoma).

Risk Behavior:

Excluded:

Current alcohol or illicit drug use that may interfere with drug absorption or ability to take oral medication.

Required:

NRTI therapy at day of entry and up to screening.

Required:

>= 12 weeks of NRTI therapy.