[Fundamental and clinical studies on S6472 (a new prolonged acting preparation of cefaclor) in the urological field].

Fundamental and clinical studies on S6472, a new prolonged acting preparation of cefaclor, were performed and the following results were obtained. Serum level and urinary excretion. 750 mg of S6472, 500 mg of cefaclor (CCL) and 500 mg of cephalexin (CEX) were orally administered in 6 healthy adult volunteers by the cross over method to measure serum level and urinary excretion. The serum level-time curve of S6472 showed 2 peaks at 1 and 6 hours after administration. The peak serum level of S6472 was 4.2 micrograms/ml and 2.9 micrograms/ml, respectively, 1 and 6 hours after administration. The peak serum level of CCL and CEX was 5.8 micrograms/ml and 12.1 micrograms/ml, respectively, 2 hours after administration. The urine level-time curve of S6472 also showed 2 peaks at 0-2 and 4-6 hours after administration and the peak urine level was 1,320 micrograms/ml and 994 micrograms/ml, respectively, 0-2 and 4-6 hours after administration. The peak urine level of CCL was 1,337 micrograms/ml, 0-2 hours after administration and that of CEX was 2,079 micrograms/ml, 2-4 hours. The mean urinary excretion of S6472, CCL and CEX was 56%, 69% and 94% of dose at 12 hours after administration. Clinical evaluation. S6472 was tried in 200 cases of various urinary tract infections. For one group of 85 cases with acute uncomplicated cystitis, clinical effects were evaluated as excellent in 40 cases, moderate in 42 cases and poor in 3 cases, and the overall clinical effectiveness rate was 96.5%. For another group of 68 cases with complicated urinary tract infection, clinical effects were evaluated as excellent in 9 cases, moderate in 27 cases and poor in 32 cases, and the overall clinical effectiveness rate was 52.9%. Side effects. Side effects were observed in 7 cases with diarrhea, epigastralgia, stomatitis, eruption and facial swelling. Administration of S6472 was discontinued in 2 cases, but in 7 cases all symptoms were transient.