Dose Ranging Trial of Tipranavir/Ritonavir in Treatment-Experienced HIV Infected Individuals

This study will be conducted in HIV+, multiple ARV medication experienced patients. All patients must have received treatment from each of three ARV classes: NRTIs, NNRTIs and PIs, have received at least two PI-based ARV regimens (may include the current regimen) with a viral load greater than or equal to 1000 copies/mL at the time of study entry. The two separate PI-based regimens must each have been taken for at least 3 months. At least one resistance-conferring PI-mutation (from a pre-established panel) must be present. Baseline genotypic screening will be performed and will be used in conjunction with ARV medication history to determine new background therapy for each individual subject to use. Following genotypic screening at baseline, qualifying subjects will be randomized to one of three blinded treatment regimens. Subjects will discontinue their current protease inhibitor and initiate TPV/RTV for 2 weeks of functional monotherapy. Thereafter, the background ARV medications will be optimized and subjects will remain on blinded TPV/RTV plus optimized background therapy for the duration of the trial. Trial duration ranges between 12-32 weeks, depending on when the subject is entered into the trial and the interim analyses for determination of optimized TPV/RTV regimen is completed. On determination of the optimal TPV/RTV dose, subjects may opt to continue open-label treatment.