[Evidence-based therapeutic drug monitoring of atazanavir]

Abstract

The HIV protease inhibitor atazanavir presents a wide inter-individual variability related to an intense hepatic metabolism. Dose-dependent elevations of bilirubin have been frequently reported with atazanavir. Relative to literature, the atazanavir therapeutic drug monitoring can it be proposed? In naïve HIV-infected patients, the probability of achieving an undetectable HIV viral load at W48 was significantly associated with a plasma trough concentration (C(min)) of atazanavir >200 ng/mL. Studies in HIV-infected pre-treated patients reported that the genotypic inhibitory quotient was a predictive factor of the virologic response with a threshold value around 200 ng/mL/mutation. Concerning the exposure-toxicity relationship, the risk of occurrence of grade 3-4 hyperbilirubinemia was more frequently associated with C(min) > 750-800 ng/mL. Non-randomized studies have reported the interest of atazanavir therapeutic drug monitoring to optimize the virologic response and prevent severe bilirubin elevations. Therefore, the level of evidence of the interest of atazanavir therapeutic drug monitoring is recommended.