Laboratory Studies And Clinical Evaluation Of Carumonam In Respiratory Infections

Carumonam (CRMN, AMA-1080), a novel synthetic monocyclic β-lactam antibiotic, was basically and clinically evaluated with the following results: 1) Antimicrobial activity: CRMN was specifically active against aerobic Gram-negative bacteria including Pseudomonas aeruginosa. Its activity against Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, Enterobacter cloacae, Enterobacter aerogenes and P. aeruginosa was in general equal or superior to that of the third-generation cephems such as ceftizoxime, cefoperazone and latamoxef. 2) Carumonam level in serum and sputum: CRMN was drip infused for 1 h to five patients with chronic respiratory infections at a dose of 1 or 2 and its serum and sputum levels were assayed microbiologically. Peak serum levels were 33.5—64.7 μg/ml with the 1 g dose and 88.4—146.6μg/ml with the 2 g dose at the end of drip infusion. Peak sputum levels were 1.21—6.56 μg/ml (2 g) at 2 to 4 h after infusion. The average ratio of peak levels in sputum to those in serum was 3.7 and 5.6%, respectively. 3) Clinical results: CRMN was administered to 13 patients with various respiratory infections. Clinical response was excellent in 2, good in 6, fair in 3 and poor in 1 patient, and 1 patient was not evaluable. The overall efficacy rate was 66.7%. In one patient S-GPT and urobilinogen values were transiently elevated mildly to moderately. We therefore conclude that CRMN is a useful antibiotics in treating patients with respiratory infections due to aerobic Gram-negative bacteria.