Laboratory and clinical studies on TMS-19-Q

Laboratory and clinical studies on TMS-19-Q, a new macrolide antibiotic, were carried out and the results were as follows 1) Antimicrobial activity The minimal inhibitory concentrations (MICs) of TMS-19-Q against 50 clinical isolates of Mycoplasma pneumoniae (M. pneumoniae) ranged from 0.0035 to 0. 06 μg/ml. The peak MIC of TMS-19-Q was 0. 015 μg/ml, which was superior to those of josamycin (JM) and oleandomycin (OL). The growth inhibitory effect of TMS-19-Q against M. pneumoniae in test tube revealed bactericidal activity in the concentration of 0.5 and 1.0 μg/ml. In the treatment of hamster experimentally infected with M. pneumoniae the viable organisms in the lungs decreased to 102cells/ml on the 3rd day. On the 10 th day of drug treatment, 80% (8 out of 10) of the hamsters receiving TMS-19-Q showed no viable M. pneumoniae cells upon the culture of their lungs. The antimicrobial activity of TMS-19-Q against 50 strains of Legionella pneumophila was almost same as that of erythromycin (EM). The MICs of TMS-19-Q against 155 clinical isolates (Streptococcus pneumoniae 47, Streptococcus pyogenes 54, Streptococcus faecalis 27 and Staphylococcus epidermidis 27) were compared with those of JM and EM. The antibacterial activity of TMS-19-Q was superior to that of JM and was almost equal to that of EM. 2) Absorption and excretion in humans The average peak plasma level of TMS-19-Q in six healthy adult volunteers after single oral dosage of 600 mg with TMS-19-Q·O tablet was 0. 5 μg/ml; while same dosage of TMS-19-Q with GC tablet to same volunteers yielded an average peak plasma level of 1.8 μg/ml. When TMS-19-Q·GC tablet (600mg) was given to four patients with chronic respiratory tract infections, the peak sputum level was 0. 38 μg/ml and the urinary excretion rate was about 3% on average. 3) Clinical evaluation and adverse reaction Twenty-nine patients with respiratory tract infections were treated with TMS-19-Q·GC tablet at daily dose of 600mg for 4 to 19 days. In clinical response of 29 patients, excellent was 10, good was 15, fair was 2, poor was 2. Over all efficacy rate was 86. 2%. Neither side effects nor changes in laboratory data attributable to the drug were observed in these patients.