Arbekacin postmarketing clinical study

We conducted a multicenter postmarketing clinical study to obtain arbekacin sulfate (ABK) pharmacokinetic parameters in children younger than 6 years, with the following results: Patients were divided into group A; neonates and low-birth-weight (LBW) infants (n=7) and group B; infants and children (n=3). A dose of 2-3 mg/kg of ABK was administered intravenously by infusion for 30 min, and pharmacokinetic parameters were obtained. Two LBW infants and one neonate were excluded because of infusion errors and administration of a steroid drug that may affect ABK efficacy. Maximum plasma concentrations (C_max) were 6.64±1.13 (μg/mL) for group A (n=4) and 7.91±1.43 (μg/mL) for group B (n=3), indicating no significant difference (p=0.2429). Steady-state volume of distributions (Vd_ss) were 0.382±0.045 (L/kg) and 0.304±0.060 (L/kg), and plasma half-lives (t_1/2) 3.20±0.91 (h) and 1.73 ±0.43 (h) for groups A and B. Although these were not significant different between groups (p=0.1049 and 0.0515), group A means were larger. Total body clearance (Cl_tot) was 0.091±0.017 (L/h/kg) and 0.154 ±0.030 (L/h/kg) for groups A and B. The group B mean was significantly larger (p=0.0148). Predicted plasma concentrations 12 h after infusion (trough), calculated ABK pharmacokinetic parameters, were 0.42±0.25 (μg/mL) for groups A and B. ABK plasma concentration profiles of these children were similar to those of adults, which were recommended in consideration of clinical effects and safety.