Probability of Optimal Target Attainment of Amikacin in Patients With Febrile Neutropenia During Treatment for a Hematological Disorder: a Prospective, Single-centre Study and PKPD-analysis

Amikacin is an aminoglycoside (AG) that exerts a rapid bactericidal effect against many Gram-negative pathogens. Its pharmacological effect depends on the peak concentration achieved. However, a common side effect of AG is dose-dependent acute kidney injury (AKI), especially when administered over several days due to an accumulation of the drug in the proximal renal tubular cells. In patients in advanced stage of a hematological disease, low body weight influences amikacin pharmacokinetics and pharmacodynamics (PKPD) and increases its clearance. However, there is little known about amikacin PKPD in patients with febrile neutropenia (FN). Whereas the therapeutic efficacy is associated with the peak concentration of AG, toxicity of AG depends on the area under the curve (AUC) or trough level of the drug. When using the AUC to predict renal toxicity, an AUC between 200 and 300 mg/L * h of amikacin has been proposed as a potential threshold for renal toxicity. At the University Hospital Basel (USB), amikacin is administered intravenously (iv) as once daily infusion combined with cefepime or piperacillin/tazobactam immediately after the occurrence of a fever spike in patients with FN. After the iv administration of amikacin, peak concentration is achieved after 30-60 min. The in-house guidelines recommend the administration of lower amikacin dosages compared to other published studies (15 mg/kg body weight vs. 20 mg/kg or up to 30 mg/kg). It remains unclear if adequate peak concentrations are achieved in patients with FN, when lower amikacin doses are administered. The aim of this study is to investigate the probability of optimal pharmacological target attainment (Cmax ≥60 mg/L) during amikacin treatment among patients with FN treated for hematological disorder in order to evaluate the in-house amikacin dosage recommendations. The current project includes the sampling of biological material during hospital admission and the collection of health-related personal data.