Aim To investigate the pharmacokinetics of NM394 （an active metabolite of prulifloxacin） and evaluate the dose relationship and accumulation characteristics after single and multiple doses of prulifloxacin. Methods Twelve healthy volunteers were given 132.1 mg, 264.2 mg, and 396.3 mg of prulifloxacin tablets in a randomized 3 × 3 crossover design test for single doses trial. With one-week washout period, 264.2 mg of prulifloxacin tablets were given for multiple doses trial. NM394 in plasma was determined by a sensitive HPLC method and its pharmacokinetic parameters were analyzed and evaluated by Drug and Statistics saftware （version 1.0）. Results The Cmax, Tmax, t 1/2, AUC0-24, and AUC0-∞ of NM394 after single doses of 132.1 mg, 264.2 mg, and 396.3 mg of prulifloxacin tablets were 0.64 ± 0.25 μg· mL^-1, 1.06 ± 0.35 μg· mL^-1, and 1.45 ± 0.44 μg· mL^-1 , respectively; Tmax 0.94±0.22 h, 1.02±0.17 h, and 0.98±0.23 h, respectively; t 1/2 8.37±0.70 h, 7.70±0.82 h, and 7.78 ± 0.77 h, respectively; AUC0-24 2.93 ± 0.78 μg· mL^-1· h, 4.39 ± 1.05 μg· mL^-1· h, and 5.55± 1.32 μg·mL^-1 ·h, respectively; AUC0-∞ 3.32±0.84 μg·mL^-1 ·h, 4.82± 1.06 μg·mL^-1 ·h, and 6.10 ± 1.38 μg·mL^-1· h, respectively. And the Cmax, Tmax, t,1/2, AUC0- 24, and AUC0-∞ after multiple doses of 264.4 mg prulifloxacin tablets were 1.20 ± 0.33 μg· mL^- 1, 0.67 ± 0.12 h, 7.38 ± 1.03 h, 5.58 ± 1.25 μg· mL^-1·h, and 6.09 ± 1.24 μg· mL^-1· h, respectively. Conclusion The Cmax and AUC of NM394 are in high correlation with given prulifloxacin doses. There are no differences in pharnacokinetic characteristics of NM394 between single and multiple doses. No accumulation in plasma is observed after multiple doses of 264.2 mg per day for 7 d.
