Fosfomycin distribution in the lower urinary tract after administration of fosfomycin trometamol salt.

Fosfomycin trometamol (FT) is a new fosfomycin salt with pharmacokinetic characteristics allowing hypothesis of its use in the single-dose therapy of lower urinary tract infections. In this study the diffusion of fosfomycin into bladder mucosa and urine after administration of a single oral dose of FT (3 g) was evaluated in patients affected by bladder or prostatic carcinoma having to undergo surgery. The administration of FT was scheduled in order to obtain blood, urine and tissue samples, to be collected during surgical operation at different times post administration. The peak concentrations in serum and bladder mucosa were detected within 3 h and 6 h respectively. Fosfomycin concentrations in bladder mucosa proved to be higher than the MICs of the most common urinary tract pathogens for at least 36 h. In urine, fosfomycin reached concentrations markedly higher than those found in serum and bladder mucosa, antibacterial levels lasting until the 48th hour post dosing. Fosfomycin trometamol, because of its pharmacokinetic and pharmacodynamic properties, appears to be suitable for single-dose therapy of uncomplicated UTIs.