Ritonavir (ABT-538)/Indinavir Combination Treatment in HIV-Infected Patients Previously Receiving Indinavir 800 mg TID

Inclusion Criteria Patients must have: HIV infection. CD4 cell count greater than 100 cells/microliter. HIV RNA levels greater than 400 copies/microliter using the Roche Ultrasensitive assay. No acute illness. Consent of parent or guardian if less than legal age. No prior enrollment in this study. All entry criteria for this study met within 15 days prior to enrollment. Exclusion Criteria Co-existing Condition: Patients with any of the following symptoms or conditions are excluded: Any condition that in the opinion of the investigator may obscure proper observation of the safety or activity of the treatment regimens used in this study. Concurrent Medication: Excluded: Concurrent non-nucleoside reverse transcriptase inhibitors as part of the antiretroviral regimen. Any of the following medications with ritonavir: midazolam, clorazepate, diazepam, estazolam, flurazepam, triazolam, zolpidem, quinidine, amiodarone, encainide, flecainide, propafenone, bepridil, terfenadine, astemizole, cisapride, bupropion, clozapine, rifabutin, meperidine, propoxyphene, piroxicam, pimozide, dihydroergotamine, and ergotamine. Any of the following medications with indinavir: terfenadine, astemizole, cisapride, triazolam, midazolam. No requirement for rifampin or ketoconazole. Any concurrent treatment with other protease inhibitors. Other concurrent medication (including over-the-counter medicine or alcohol) without the knowledge and permission of the primary investigator. Patients with the following prior conditions are excluded: History of significant drug hypersensitivity. Psychiatric illness that precludes compliance with the protocol. Receipt of investigational drug within 30 days prior to administration of study drug. History of acute or chronic pancreatitis. Anticipation of poor patient compliance with protocol. Prior Medication: Excluded: Prior treatment with ritonavir. Risk Behavior: Excluded: History of active substance abuse (i.e., recreational drugs or alcohol). Included: - Indinavir 800 mg three times a day plus unspecified nucleosides for at least 3 months.