The purpose of this study is to evaluate tolerability of darunavir (PREZISTA) or etravirine (INTELENCE) in patients infected with human immunodeficiency virus type 1 (HIV-1) who are naïve to these medications and in patients who have experienced tolerability issues on their current or prior combination antiretroviral therapy (cART). The tolerability is evaluated by switching the patients from their previous or current combination antiretroviral therapy (cART) to either darunavir or etravirine.

This is an open label (all people know the identity of the intervention.), multicenter (study conducted at multiple sites), observational study (individuals are observed for certain outcomes) of darunavir and etravirine in patients infected with HIV-1 who are naïve to these medications and who have experienced tolerability issues on their current or prior combination antiretroviral therapy (medicines used for treatment of HIV). PREZISTA is indicated for naïve HIV patients (someone who has never used HIV drugs) and treatment-experienced HIV patients and INTELENCE is indicated for treatment-experienced patients who have failed prior therapy and have HIV-1 strains resistant to multiple antiretroviral agents (HIV-1 strains are able to survive the exposure of the multiple antiretroviral agents), including Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs). In this study patients will receive either darunavir (PREZISTA) or etravirine (INTELENCE) and physician selected optimized background agents (other antiretroviral medicines), as permitted by the local formulary and supported by the current Canadian Product Monograph. 90 patients will participate in this study (75 Patients planned for the darunavir group and 15 patients planned for the etravirine group). The total duration of the study will be 24 weeks. Safety and tolerability will be evaluated at screening (14 days prior to Day 1), baseline (patient's medical status before any treatment or research is done) at Day 1, Week 4, Week 12 and Week 24. Tolerability will be evaluated using HIV Symptom Distress Module (HIV-SDM) also referred to as the HIV Symptom Index (HSI) which is a self-completed questionnaire to evaluate symptoms and measure the presence and bothersomeness of side effects commonly seen with HIV and antiretroviral treatment over the last 4 weeks (20 questions about all symptoms which the patient might have had during the past four weeks). Higher scores indicate the presence of more symptoms and/or a greater degree of distress related to the 20 symptoms. In HIV-SDM data is collected to see the benefit of switching to either darunavir or etravirine.

Inclusion Criteria:

• Have a documented HIV-1 infection
• Have 1 or more significant symptoms with at least grade 2 toxicity on the Division of AIDS Toxicity "DAIDS grading scale" on current or prior combination antiretroviral therapy (cART) regimen (current or prior cART including regimens consisting of 2 Nucleoside reverse transcriptase inhibitors (NRTIs) and a third agent with the exception of darunavir or etravirine)
• Have stable response to current cART ie, have an HIV-plasma viral load [number of virus in blood] at screening <400 copies/mL (undetectable) or last plasma viral load on prior regimen within the previous 6 months <400 copies/mL)
• Must not have resistance to Primary HIV protease inhibitor medicines

Exclusion Criteria:

• Has been Infected with HIV-2 - Has received previous treatment with darunavir or etravirine or non-HAART (Highly Active Antiretroviral Therapy) regimen
• Has had prior virologic failure to 2 or more regimens or single virologic failure on prior cART
• Has a documented resistance to darunavir and etravirine
• Is currently using any drug contraindicated in the current Canadian Product Monograph for darunavir or etravirine

Patients infected with human immunodeficiency virus type 1 who have experienced tolerability issues on their current or prior ccombination antiretroviral therapy regimen and for whom a regimen including darunavir and/or etravirine is clinically indicated.