Safety and Efficacy Study of Switching From Epzicom to Truvada

Inclusion Criteria

• Adult (greater than or equal to 18 years) males or non-pregnant, non-lactating females
• HIV-1 infected subjects currently receiving a ritonavir-boosted protease inhibitor and fixed-dose ABC/3TC regimen continuously for greater than or equal to 3 months
• HIV infection as documented by a validated HIV antibody enzyme-linked immunosorbent assay (ELISA) and confirmed by one of the following:
• Immunoblot detection of HIV antibody
• Positive HIV-1 blood culture
• Positive HIV-1 serum P24 antigen
• HIV-1 plasma viremia greater than 1000 copies/mL by polymerase chain reaction (PCR) or branched-chain deoxyribonucleic acid (bDNA) method
• Detection of proviral DNA by PCR

(If confirmation of HIV infection is not available then repeat testing of HIV antibody will be required)

• Two consecutive plasma HIV-1 RNA concentration less than 200 copies/mL. The two HIV-1 RNA determinations ensure that the subject has been virologically-suppressed for at least 3 months prior to study entry:
• The subject must have a plasma HIV-1 RNA level less than 200 copies/mL using the AmpliPrep/Taqman HIV-1 Test or Roche Amplicor HIV-1 Monitor Test Version 1.5 Ultrasensitive method at least 3 months prior to the screening visit, as the "qualifying HIV-1 RNA."
• HIV-1 RNA less than 200 copies/mL measured by bDNA (Chiron 3.0) may be used as a qualifying HIV-1 RNA for entry to the study but not for the confirmatory HIV-1 RNA.
• The subject must have a confirmed second plasma HIV-1 RNA less than 200 copies/mL at screening, as the "confirmatory HIV-1 RNA."
• The subject must not have a plasma HIV-1 RNA greater than or equal to 200 copies/mL between the qualifying and confirmatory HIV-1 RNA measurements.
• Subjects receiving lipid-lowering agents (LLA) will be allowed; however, LLAs must be stable for greater than or equal to 3 months prior to study entry.
• Adequate renal function defined as a calculated CLcr greater than or equal to 50 mL/min according to the Cockcroft-Gault formula
• Negative serum pregnancy test (females of childbearing potential only)
• Hepatic transaminases alanine aminotransferase (ALT) and aspartate aminotransferase (AST) less than or equal to 5 X upper limit of normal
• Males and females (of childbearing potential, ie, a non-menopausal female or a female with menopause < 2 years, and who has not had a hysterectomy, bilateral oophorectomy, or medically documented ovarian failure; this definition includes a young woman who has not yet started menstruating), and must agree to avoid pregnancy by sexual abstinence, or utilization of a highly effective method of birth control throughout the study period and for 30 days following discontinuation of study drug
• The ability to understand and sign a written informed consent form, which must be obtained prior to initiation of any study procedures

Exclusion Criteria

• Subjects receiving ABC/3TC and a PI without ritonavir
• Subjects receiving other ARV agents (eg, 2 protease inhibitors boosted with low-dose ritonavir (ie, "double-boosted PI regimens"), nonnucleoside reverse transcriptase inhibitors [NNRTIs], integrase inhibitors, TDF, or other nucleoside reverse transcriptase inhibitor [NRTIs]) in addition to ABC/3TC and a ritonavir-boosted protease inhibitor
• Have known resistance to any of the study agents at any time in the past including NRTI resistance mutations (including but not limited to K65R, L74V/I, M184V/I, or thymidine analog mutations) and/or PI resistance mutations
• A new acquired immunodeficiency syndrome (AIDS) defining condition diagnosed (with the exception of CD4 criteria) within 30 days of baseline
• Previous therapy with agents with systemic myelosuppressive, pancreatoxic, hepatotoxic or cytotoxic potential within 3 months of study start or the expected need for such therapy at the time of enrollment
• Proven or suspected acute hepatitis in the 30 days prior to study entry
• Anticipated need to initiate drugs during the study that are contraindica