A Study of Amprenavir in HIV-Infected Patients

Inclusion Criteria Patients must have: * Documented HIV-1 infection. * Evidence of failure or intolerance (have experienced a treatment-limiting toxicity) to standard protease inhibitor therapy and, in the judgment of the physician, be unable to construct a viable treatment regimen without APV. * Consent of parent or guardian if less than 18 years old. Exclusion Criteria Co-existing Condition: Patients with the following symptoms or conditions are excluded: * Malabsorption syndrome or other gastrointestinal dysfunction which might interfere with drug absorption or render the patient unable to take oral medication. * Serious medical conditions such as diabetes, congestive heart failure, cardiomyopathy, or other cardiac dysfunction, which, in the opinion of the investigator, would compromise the safety of the patient. * Hepatic failure. * Renal failure requiring dialysis. Patients with the following prior conditions are excluded: History of clinically relevant pancreatitis or hepatitis within the last 6 months. Prior Medication: Excluded: * Previous treatment with APV. * Patients currently participating in, or who would qualify for or have access to, an enrolling study of APV (ACTG 398 and ACTG 400). Risk Behavior: Excluded: Patients with current alcohol or illicit drug use which, in the investigator's opinion, may interfere with the patient's ability to comply with the requirements of the study. Required: Currently taking at least one nucleoside analogue or protease inhibitor, in addition to amprenavir. Required: * Received prior treatment with one or more protease inhibitors. * Patient must be naive to at least one or more nucleoside analogue, non-nucleoside analogue, or protease inhibitor drugs.