Penetration of prulifloxacin into gynaecological tissues after single and repeated oral administrations

This study aimed to evaluate the penetration into gynaecological tissues of ulifloxacin, the active metabolite of prulifloxacin, a once-daily fluoroquinolone administered once or in repeated doses.

This was an open-label, randomised study that included 20 consenting female inpatients (age range 40-65 years) requiring total simple hysterectomy as a result of benign disease. Three groups of patients were enrolled: group A (four patients whose gynaecological tissue samples were used to set up the bioanalytical method); group B (eight patients treated 3 hours before surgery with one 600 mg tablet of prulifloxacin); group C (eight patients treated with prulifloxacin 600 mg once daily for 3 days and undergoing surgery 3 hours after the last dose). Patients to be treated with prulifloxacin were randomly allocated to group B or C. During surgery, samples of blood were collected jointly with healthy tissue removed from the endometrium, proximal fallopian tube, vaginal posterior fornix and portio vaginalis. Ulifloxacin concentrations in plasma and gynaecological tissues were determined by a liquid chromatography-tandem mass spectrometry (LC-MS/MS) bioanalytical method. An intrastudy assessment of the bioanalytical method performance was also conducted for plasma and tissues using calibration and quality control data (spiked samples).

Ulifloxacin mean concentrations were always higher in group C than in group B patients, both in plasma (0.76 vs 0.53 microg/mL) and in gynaecological tissues, namely fallopian tube (1.38 vs 0.81 microg/g), posterior fornix (1.48 vs 1.05 microg/g), portio vaginalis (1.46 vs 1.45 microg/g) and endometrium (2.20 vs 1.39 microg/g), as expected after repeated drug administrations. Tissue concentrations observed after repeated administrations were generally higher than the ulifloxacin minimum inhibitory concentrations for pathogens more frequently involved in gynaecological bacterial infections. The mean tissue/plasma ratios ranged between 1.5 and almost 3.

The results of this study are promising but not fully predictive of clinical or microbiological efficacy for prulifloxacin. There is a need for appropriate clinical trials confirming that prulifloxacin is a useful therapeutic tool in patients with gynaecological bacterial infections.