[Absorption and excretion studies of S6472 (sustained release preparations of cefaclor)]

In order to see absorption and excretion of S6472 (sustained release preparations of cefaclor (CCL], 3 studies regarding, 1) influence of meals (single dose of 375 mg in capsule form), 2) dose response (single dose of 375 mg vs. 750 mg in granule form) and 3) continuous administration (twice-a-day administration of 750 mg in granule form for 8 days) were conducted in 15 healthy adult male volunteers using capsule and granule forms of S6472. The following is the summary of the results from the above studies: Tolerance. In the above 3 studies, none of the 15 volunteers complained of subjective abnormalities. In the clinical laboratory tests performed before the administration of S6472 and at the next day of the completion of the studies, the values from the laboratory tests were within normal range. Influence of meals. The average time for peak plasma level of CCL and decrease in the plasma level following the administration of S6472 were the fastest in the fasted volunteers, followed by the volunteers with light meals and usual meals. From this, it was confirmed that plasma levels of CCL were maintained for longer period of time in the non-fasted volunteers than in the fasted volunteers. In the volunteers who had light and usual meals, the peak plasma levels, AUC of the plasma levels and urinary recovery rate were almost the same. Influence by amount of meals was scarcely observed. Dose response. Mean serum levels and their AUC in the volunteers receiving 750 mg of S6472 were approximately twice as much as those in the volunteers receiving 375 mg of S6472, and dose response between the 2 doses was confirmed. Continuous administration. Mean serum levels and their AUC at the first dose and the 15th dose (final dose) were almost the same. In the continuous administration of S6472 for 8 days (15 doses), no accumulation of CCL in the body was observed.