Loracarbef (LY163892) versus cefaclor and norfloxacin in the treatment of uncomplicated pyelonephritis.

Optimal therapy for pyelonephritis requires the immediate administration of an effective broad-spectrum antibiotic. Because conventional oral antibiotics such as the sulfonamides and the aminopenicillins are limited by the development of resistant bacteria associated with this common disease, the therapeutic effectiveness of a new oral carbacephem antibiotic was investigated. Two double-blind, randomized clinical trials of loracarbef (LY163892) were conducted. A total of 245 patients (greater than or equal to 18 years old) with uncomplicated pyelonephritis were enrolled in parallel studies. One study compared loracarbef with cefaclor; the other compared loracarbef with norfloxacin. In the combined patient population, 119 patients were treated with loracarbef (400 mg twice daily), 43 with cefaclor (500 mg three times daily), and 83 with norfloxacin (400 mg twice daily). All treatment regimens continued for greater than or equal to 14 days. A total of 68 patients in the loracarbef group, 25 in the cefaclor group, and 43 in the norfloxacin group qualified for efficacy analysis. Escherichia coli was the causative pathogen in 85.0% of these patients. Successful posttherapy clinical and bacteriologic responses were similar for all three study drugs: 94.1 and 86.8%, 96.0 and 80.0%, 97.7 and 88.4% for loracarbef, cefaclor, and norfloxacin, respectively. Late posttherapy clinical responses were 87.4, 83.3, and 91.7% for the loracarbef, cefaclor, and norfloxacin groups, respectively. Bacteriologic responses for the three groups were 79.6, 60.0, and 88.9%. The most frequent adverse effects (headache, diarrhea, and nausea) were experienced by three patients (2.5%) in the loracarbef group; headaches were noted in two (4.7%) cefaclor patients, diarrhea was noted in three (7.0%) patients in the cefaclor group, and nausea was noted in four (9.3%). Gastrointestinal events were noted in four patients (4.8%) in the norfloxacin group. The data demonstrate that loracarbef is comparable in efficacy and safety to both cefaclor and norfloxacin as oral therapy for uncomplicated pyelonephritis.