Open-label study of a regimen of antiretrovirals for the treatment of AIDS-KS. This study will be conducted at a single site, the Parirenyatwa Hospital KS Clinic.

Step 1 was conducted to determine the extent of clinical resolution of AIDS-KS disease in response to treatment with antiretroviral therapy and to investigate whether clinical resolution of KS is associated with suppression of KSHV replication.

Step 2 was developed to then evaluate the clinical, immunological, and virological effects of a switch from a twice-daily all-nucleoside reverse transcriptase inhibitor (NRTI) antiretroviral regimen to a once-daily regimen of 2 NRTIs plus a ritonavir-boosted protease inhibitor in persons with AIDS-KS and good virologic suppression an all NRTI regimen.

Step 3 was included to evaluate the clinical, immunological, and virological effects of intensification with a ritonavir-boosted protease inhibitor in persons with AIDS-KS who have virological failure on an all NRTI regimen.

To identify factors associated with successful treatment of KS with antiretroviral therapy and to determine if highly active antiretroviral therapy improves survival and quality of life for persons with AIDS-KS in Zimbabwe.

A secondary objective is to investigate the durability of HIV-1 suppression by the combination of ABC/3TC/ZDV in persons infected with HIV-1 subtype C and to evaluate the timing and characteristics of mutations in HIV-1 reverse transcriptase in subjects who fail to achieve, or to maintain suppression of HIV-1 replication during treatment with ABC/3TC/ZDV.

An important objective is to assess adherence to a simplified antiretroviral regimen in a resource-limited setting.

The study will evaluate the clinical, immunological, and virological effects of a switch from a twice-daily all-nucleoside reverse transcriptase inhibitor (NRTI) antiretroviral regimen to a once-daily regimen of 2 NRTIs plus a ritonavir-boosted protease inhibitor in persons with AIDS-KS and good virologic suppression on ABC/3TC/ZDV (see above).

Inclusion Criteria:Completion of at least 96 weeks of treatment with ABC/3TC/ZDV on protocol Step 1.

• Currently receiving ABC/3TC/ZDV on Step 1/initial open-label allNRTI phase of study.
• Plasma HIV-1 RNA < 400 copies/mL on the most recent plasma HIV-1 RNA performed within 4 weeks of Step 2 entry.
• Willing to potentially switch to a new antiretroviral regimen.
• In the opinion of the site investigator currently has clinical evidence of active KS disease.

Exclusion Criteria

• None