sy-5555 and Impetigo

Laboratory and clinical studies were performed on SY5555, the first penem oral antibiotic developed in Japan, in the pediatric field. The following results were obtained. 1. Antibacterial activities of the drug against 42 strains of Streptococcus pneumoniae clinically isolated in 1993 were compared to those of 13 other drugs mainly composed of beta-lactam preparations. Minimum inhibitory concentration (MIC) values of SY5555 were below 0.39 micrograms/ml for all strains examined, thus the drug showed an excellent activities against benzylpenicillin (PCG)-resistant strains as well. When the antibacterial effects of individual drugs were compared using MIC50 and MIC90 as indices, SY5555 was the most effective against PCG-sensitive strains and similar to cefazolin (CEZ), cefotaxime (CTX), cefuzonam (CZON), amoxicillin (AMPC) and imipenem (IPM). It also showed excellent antibacterial effects against moderately PCG-resistant strains, and the activities were similar to IPM. Activities of SY5555 on highly PCG-resistant strains were similar to those of CTX, CZON and IPM. 2. SY5555 at a dose of 5 mg/kg or 10 mg/kg was administered to 16 pediatric patients in the fasting state or after meal to examine its plasma concentration and urinary excretion rate. The fecal excretion was measured in 5 affected children treated with this drug. When the drug at a dose of 5 mg/kg was administered to 11 older children, 5 with ages 5-12 years and 6 with ages 10-13 years in the fasting state and after meal, respectively. Peak plasma levels were reached at 1 hour after administration in the two groups, and they were 0.93 +/- 0.25 and 2.44 +/- 1.25 micrograms/ml, respectively. The plasma levels then decreased gradually with half-lives of 1.95 +/- 1.09 and 0.72 +/- 0.21 hours, respectively. Urinary recovery rates in the first 6 hours after administration were 1.98 +/- 0.82 and 4.13 +/- 1.40%, respectively. In 3 cases (6-9 years) treated with the drug at a dose of 10 mg/kg after meal, a peak of 1.58 +/- 0.81 micrograms/ml appeared 1 hour after administration with a half-life of 1.08 +/- 0.30 hours and with the urinary recovery rate in the first 6 hours after administration of 3.46 +/- 1.03%. When the drug at a dose of 10 mg/kg was administered to 2 infants (2-3 months post partum) after meal, a peak plasma level of 3.74 micrograms/ml appeared 1 hour after administration with a half-life of 1.19 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adolescent; Bacterial Infections; Carbapenems; Child; Child, Preschool; Female; Half-Life; Humans; Impetigo; Infant; Male; Microbial Sensitivity Tests; Patient Compliance; Respiratory Tract Infections; Urinary Tract Infections

Pharmacokinetic and clinical studies on SY5555, a new oral penem antibiotics, were performed in pediatric infections and the following results were obtained. 1. Pharmacokinetics studies Pharmacokinetics of SY5555 was studied in 5 children (5y1m-10y11m) using doses of 5 mg/kg (n = 3) and 10 mg/kg (n = 2). The average peak plasma levels were 0.65 microgram/ml at 1 or 2 hours after administration of 5 mg/kg and 2.12 micrograms/ml at 1 or 2 hours after administration of 10 mg/kg, and the plasma half-lives were 0.81 and 1.08 hours, respectively. Average cumulative urinary recovery rates at 0-6 hours were 2.97 and 3.96%, respectively. 2. Clinical studies SY5555 was administered to 45 patients with various infectious diseases (2 with acute pharyngitis, 8 with acute tonsillitis, 4 with lacunar tonsillitis, 3 each with acute bronchitis, pneumonia and pertussis, 7 with scarlet fever, 3 with impetigo contagiosa, 6 with acute urinary tract infections, 2 with balanoposthitis and 1 each with cervical lymphadenitis, S.S.S.S., vulvitis and acute colitis) at daily doses between 3.4-10 mg/kg, t.i.d., for 3-14 days. Clinical responses were excellent in 27 patients, good in 15 patients, fair in 1 patient, and poor in 2 patients, and the efficacy rate was 93.3%. Causative organisms were examined and 39 strains of 11 species were identified. The eradication rate was 78.9%. Side effects were observed in 1 patient with diarrhea. An abnormal laboratory test value was observed in 1 patient with elevation of eosinophils. The above results suggest that SY5555 may be a very useful and safe drug for the treatment of pediatric infection.

Topics: Administration, Oral; Adolescent; Bacterial Infections; Carbapenems; Child; Child, Preschool; Female; Humans; Impetigo; Infant; Male; Respiratory Tract Infections; Scarlet Fever; Urinary Tract Infections