A Study of ABT-378/Ritonavir Combination in HIV-Infected Patients Who Have Taken Protease Inhibitors

Inclusion Criteria Concurrent Medication: Allowed: - Antiretroviral regimen containing a protease inhibitor and one or two nucleoside reverse transcriptase inhibitors that has not changed in the last 12 weeks. Patients must have: - HIV infection with plasma HIV RNA of at least 1,000 copies/ml and less than or equal to 100,000 copies/ml at screening. Prior Medication: Allowed: Naive to or has had less than 8 weeks of at least one nucleoside reverse transcriptase inhibitor and an acceptable regimen of two nucleoside reverse transcriptase inhibitors. Exclusion Criteria Concurrent Medication: Excluded: Medications that are contraindicated with ABT-378/ritonavir for the duration of the study, such as midazolam, triazolam, terfenadine, astemizole, cisapride, pimozide, ergotamine and dihydroergotamine. Over-the-counter medicine or alcohol, without knowledge or permission of the investigator. Patients with the following prior conditions are excluded: Evidence of acute illness determined by vital signs, physical examination, or laboratory results. Clinically significant abnormal ECG results. Positive test result for drug abuse with the exception of cannabis, unless the investigator anticipates cannabis use will interfere with compliance with the study. Prior Medication: Excluded: Investigational drugs with the exception of Amprenavir within 28 days prior to the initiation of study dosing. Treatment with a non-nucleoside reverse transcriptase inhibitor. Treatment with a protease inhibitor different from the current protease inhibitor for more than 6 weeks prior to current regimen. Treatment with more than one protease inhibitor concurrently. Risk Behavior: Excluded: Active substance abuse, alcohol abuse, psychiatric illness. Presumption, by investigator, of poor compliance to regimen.