An Open Label Safety Study of Tipranavir Co-administered With Low-dose Ritonavir in Patients With Advanced HIV-1 Infection and Limited Treatment Options.

Inclusion Criteria: 1. Triple anti-retroviral class experienced patients with at least 2 previous PI-based regimens who had failed or are intolerant to currently approved HIV-1 treatments. 2. Age equal or more than 18 years 3. Patient is willing to use an effective barrier method of contraception for the duration of study participation and up to three months thereafter 4. Patient voluntarily provides written informed consent to participate, in compliance with local law. Exclusion Criteria: 1. Hypersensitivity to active ingredients or any of the excipients in tipranavir or ritonavir 2. Required use of restricted medications. 3. Female patients of childbearing potential who have a positive pregnancy test at baseline or are breast feeding. 4. Any medical condition which in the opinion of the investigator would interfere with the patients' ability to participate in or adhere to the requirements of this protocol. 5. Use of other investigational drugs, within 30 days prior to TPV boosted with ritonavir initiation and for the duration of study participation 6. Hepatic impairment evidenced by the following baseline laboratory findings: * AST or ALT more than 5X ULN or total bilirubin more than 3.5X ULN * AST or ALT more 2.5X ULN and total bilirubin more 2X ULN