Plasma kinetics of mitoxantrone in leukemic patients

The plasma kinetics of mitoxantrone (MX), a new cytostatic anthracenedione, were investigated with HPLC in five leukemic patients suffering from acute myeloid leukemia, at the dose of 24 mg m-2 infused over 30 min at constant rate. The decay of the plasma concentrations was best fitted to a three compartment model with average elimination half-lives of respectively 4.1 min (alpha-phase), 19.8 min (beta-phase) and 8.9 h (gamma-phase), a mean distribution volume of 317 l m-2 and an average total body clearance of 0.37 l min-1 m-2. The cumulative urinary recovery of unchanged MX was 7.5% of the administered dose in 4 days, with the highest elimination during the first day. No MX urinary metabolites or conjugates have been detected.