The efficacy and safety of high-dose arbekacin sulfate therapy (once-daily treatment) in patients with MRSA infection.

The efficacy and safety of once-daily high-dose arbekacin sulfate therapy for methicillin-resistant Staphylococcus aureus (MRSA) infection were evaluated, with analysis of their relationship to blood drug levels. The study was conducted in patients with pneumonia or sepsis, the cause of which was suspected to be MRSA, who were admitted to the Nagasaki University Hospital or its affiliated hospitals between January 2009 and December 2010. The initial drug dose was set at a level expected to yield the goal peak of 20 μg/ml and a trough level of less than 2 μg/ml, using the Habekacin Therapeutic Drug Monitoring analysis software. Thirteen patients were enrolled: 10 patients had pneumonia and 3 patients had sepsis. Patient mean age was 72.0 years; mean initial drug dose was 269.2 mg. Clinical efficacy at completion of treatment and bacterial eradication–reduction were achieved in 66.7% (6/9) and 62.5% (5/8) of patients, respectively. Incidence of adverse reactions was 38.5% (5/13). In analysis of efficacy in relationship to serum drug levels, the peak drug level was 22.7 ± 5.50 μg/ml, on average, and 15 μg/ml or higher in all 6 responders. Also, in patients with renal dysfunction, it seemed to be essential to ensure a certain peak drug level and to control the trough level appropriately. Although the number of patients was limited, once-daily high-dose arbekacin sulfate therapy may be highly effective, without posing any major safety problems. Further larger-scale studies are needed.