Plasma pharmacokinetics and tissue penetration of alatrofloxacin in morbidly obese individuals

Objectives: To characterise the peritoneal and subcutaneous adipose penetra tion of alatrofloxacin. If the extent of penetration of this lipophilic flu oroquinolone is adequate in patients with extensive adipose layers, it may provide better antimicrobial coverage than more commonly used antibiotics t hat are less lipophilic. Study Participants and Methods: Six morbidly obese individuals undergoing a Roux-Y gastric bypass procedure received single I-hour infusions of alatro floxacin equivalent to 300mg of its active metabolite, trovafloxacin. Blood samples were obtained over a 24-hour period and adipose tissue from subcut aneous and deep tissue sites were obtained approximately 3 hours post-infus ion of alatrofloxacin. Plasma and adipose tissue concentrations of trovaflo xacin were determined by high pressure liquid chromatography with fluoresce nce detection. Results: The mean maximum plasma concentration, area under the concentratio n-time curve, and elimination half-life of trovafloxacin were 3.6 mg/L, 37. 4 mg/L .h, and 12.1h, respectively. The mean tissue concentrations at the s ubcutaneous and deep adipose sites were 0.43 and 0.41 mug/g, respectively. Conclusions: These results indicated that the pharmacokinetics of trovaflox acin in morbidly obese individuals are similar to those in healthy control individuals. In addition, the concentrations of trovafloxacin achieved in t he adipose tissue were above the minimum inhibitory concentration of most p athogens responsible for surgical and decubitus ulcer infections.