The purpose of this study is to determine the mid levels of the tenofovir, lamivudine, and efavirenz, and 144 weeks safety and efficacy of the generic fixed dose combination of tenofovir /lamivudine/efavirenz tablets 300/300/600 mg in Thai HIV-infected patients.

The trial drug FDC of TDF/3TC/EFV is a new formulation combining fixed doses of the nucleoside reverse transcriptase inhibitors lamivudine 300 mg and tenofovir disoproxil fumarate 300 mg with the non nucleoside reverse transcriptase inhibitor efavirenz 600 mg for once daily and one-tablet HAART. Co-formulated TDF/3TC/EFV demonstrated bioequivalent to original individual EFV 3TC and TDF in Indian healthy volunteers (unpublished data). It has not been evaluated in clinical trials.

Inclusion Criteria:

• Signed informed consent
• Evidence of HIV infection
• Age> 18 years
• On a TDF/3TC/EFV (separated pills) containing HAART regimen with a VL < 50 copies within 24 weeks or ARV naïve
• eGFR >70 cc/min
• Currently having no AIDS defining illness
• No history of NRTI/NNRTI/PI failure
• Willing to adhere to the protocol requirements

Exclusion Criteria:

• Any history of taking CYP450 inhibitors or inducers drugs within 14 days of enrollment in the study
• Current pregnancy or lactating or plan to be pregnant
• Active opportunistic infection
• ALT more than 2 x upper limit
• Creatinine more than 1.5 time the upper limit
• Active drug abuse