Drug monitoring of antiretroviral drugs in children with perinatal HIV infection

Therapeutic drug monitoring is the practice of measuring the concentration of a drug in patient’s biological fluids to assess the effectiveness and safety of drug therapy. The results of determining the drug level in biological fluids can also indicate noncompliance of therapy regimen and low adherence to therapy.The aim. To compare the concentrations of some antiretroviral drugs (lopinavir, ritonavir, lamivudine, abacavir, zidovudine) in children living with HIV infection of different age groups.Methods. We examined 184 children with perinatal HIV infection who underwent therapeutic drug monitoring of nucleoside reverse transcriptase inhibitors (lamivudine, abacavir, zidovudine) and protease inhibitors (lopinavir, ritonavir). Children were divided into four age groups. Group 1 included children 1–2 years old (n = 7); group 2 – children 3–5 years old (n = 14); group 3 – children 6–11 years old (n = 78); group 4 – children 12–17 years old (n = 85). The concentration of antiretroviral drugs in blood plasma was determined using high-performance liquid chromatography with mass selective detection.Results. The lowest lopinavir concentration was found in children 12–17 years old (3782 [2117–5046] ng/ml), which was statistically significantly different from the similar values in children 6–11 years old (5614 [3521–7264] ng/ml; p = 0.011). For other antiretroviral drugs, no statistically significant differences in blood plasma concentrations were found in children of different age groups.Conclusion. The lowest lopinavir concentrations are detected in children older than 11 years. For the other studied antiretroviral drugs, this pattern was not revealed