Pharmacokinetic, bacteriological and clinical studies on cefpodoxime proxetil in the field of pediatrics

Pharmacokinetic, bacteriological and clinical studies on cefpodoxime proxetil (CPDX-PR, CS-807), a newly developed oral cephem, were carried out in the treatment of infectious diseases in the field of pediatrics. 1. Since CPDX demonstrates very powerful antimicrobial actions against such Gram-negative bacilli as Escherichia coli, Salmonella sp., Klebsiella pneumoniae and Serratia sp., such Gram-positive cocci as Streptococcus pyogenes and Streptococcus pneumoniae, and beta-lactamase producing Branhamella catarrhalis and Haemophilus influenzae, this drug was thought to be useful for the treatment of pediatric infectious diseases when main causative bacteria in the field of pediatrics were taken into account. 2. When changes in blood and urine concentrations of CPDX following the administration of this drug at 3.7 mg/kg before meal were determined, Cmax and T1/2 were found to be 2.98 micrograms/ml at 2-hour and 1.73 hours, respectively; an urinary excretion rate in the first 6 hours and a maximum urine concentration were 32.5% and 52 micrograms/ml, respectively. 3. Clinically, 8 of 8 patients with the upper respiratory tract infections (100%), 28 of 29 patients with bronchitis and/or pneumonia (96.6%), 3 of 4 patients with otitis media (75%), 2 of 2 patients with sinusitis (100%), 3 of 3 patients with the skin soft tissue infections (100%), 1 of 1 patient with bacterial enteritis (100%) and 11 of 14 patients with urinary tract infections (78.6%) responded well to the treatment with CPDX-PR, showing a 91.8% efficacy rate in all the patients treated. 4. Bacteriologically, Staphylococcus aureus, Staphylococcus epidermidis, S. pyogenes, S. pneumoniae, E. faecalis, B. catarrhalis, H. influenzae, E. coli and Salmonella typhimurium were all eradicated from 5, 1, 4, 6, 1, 5, 5, 11 and 1 patient, respectively. An eradication rate in all the patients examined was 97.5% (39/40). 5. Gastrointestinal symptoms appeared as side effects in 2 of 71 patients (vomiting in 1 and diarrhea in 1), hence, an incidence of side effects was 2.8% (2/71). As for abnormal laboratory findings, eosinophilia, thrombocytosis and increases in GOT and GPT were observed in 3 of 39 patients examined (7.7%), 1 of 39 patients (2.6%) and 2 of 34 patients (5.9%), respectively. In addition, we also examined the effect of the drug on the hemostatic system, but found no changes upon the treatment. Based on these results, it appeared that CPDX-PR was a useful and safe drug in treatment of infectious diseases in the field of pediatrics when administered 2-3 times a day at a dose of 3-6 mg/kg.