Pharmacokinetic, bacteriological and clinical studies on
SY5555 were performed in children. The results were as follows: 1. A total of 15 patients considered to have
bacterial infections were treated with
SY5555. Each dose, 5 mg/kg, was orally administered 3 times daily, for 4-11 days. Clinical efficacies of
SY5555 in 13 patients with
bacterial infections (1 with
pneumonia, 2 with
bronchitis, each 1 with
maxillary sinusitis, 2 with
otitis media, 5 with
pharyngitis, 1 each with
gastroenteritis and
pyelonephritis) were evaluated as excellent in 10 patients and as good in 3 patients with an efficacy rate of 100%. Two patients with
viral infection and
malignant lymphoma were not evaluated. Thirteen causative strains in 7 species were found in 10 patients. Streptococcus pneumoniae in 1/3, Haemophilus influenzae in 2/2, Streptococcus pyogenes 4/4, Salmonella spp. in 1/1, Escherichia coli in 1/1 were eradicated. Only one patient developed mild
diarrhea as an adverse reaction. Another patient showed elevated GPT (
glutamate pyruvate transaminase). The abnormality was mild and the patient recovered after the cessation of
SY5555 administration without specific treatment. 2. MICs of
SY5555 were examined against 33 clinical isolates.
SY5555 has low MICs against Enterococcus faecalis and other Gram-positive cocci. 3. Pharmacokinetic studies Peak plasma concentrations of
SY5555 was 1.15 micrograms/ml at a dose level of 4.9 mg/kg orally administered at fasting. Based on the above results and the broad spectrum of the anti-bacterial activities,
SY5555 appears to be a promising
antibiotics that is usable as a single agent for the primary
therapy of
respiratory tract infections, skin
soft tissue infections and
urinary tract infections in children.