Dosing of Tenofovir and Efavirenz in Antiretroviral Therapy

Inclusion Criteria: * HIV antibody positive * Chinese nationality * Naïve to antiretroviral therapy * Willing to start antiretroviral therapy * Provision of written informed consent Exclusion Criteria: * Pregnant, breastfeeding, or lactating * Females try to get pregnant during the research period * Subjects who allergic to any of the research drugs * Subjects that taking other drugs that known to impact the absorption, distribution, metabolism and excretion of the research drugs * Any serious or active medical or psychiatric illness which, in the opinion of the Investigator, would interfere with treatment, assessment, compliance with the protocol, or subject safety. This would include any active clinically significant renal, cardiac, pulmonary, vascular, or metabolic (thyroid disorders, adrenal disease) illness, or malignancy * Medical or psychiatric condition or occupational responsibilities that may preclude compliance with the protocol * Laboratory blood values: * Haemoglobin \<9.0 grams/decilitre (g/dL) * Neutrophil count \<1500/mm3 * Platelet count \<75,000/mm3 * Aspartate aminotransferase or Alanine transaminase \>3 times Upper Limit of Normal (ULN) * Total bilirubin \>3 times Upper Limit of Normal (ULN) * Subjects with an estimated creatinine clearance of \<90 mL/minute