Abacavir (ABC), Efavirenz (EFV), Lamivudine (3 TC) and Nelfinavir
(NFV) are antiretrovirals (ARV) drugs frequently prescribed to
treat human immunodeficiency virus (HIV) infection [1]. Therapy
based on antiretroviral combination is used for patient treatment
infected with HIV. Accurate dose of ARV is essential in this kind of
therapy for guaranteeing viral suppression, as well as to avoid patient
intoxication [2]. Additionally, reports show that patients
whose therapy is based on dose plasmatic ARV level, responded
better to it than individuals who followed a standard and/or fixed
regimen [3]. Due to the complexity presented by the management
of patients infected with HIV, it seems clear that any way to
monitor the pharmacokinetics of ARV therapy could substantially