Moxalactam and cefoperazone: In vitro comparison of two new beta-lactam antibiotics

The in vitro activites of moxalactam and cefoperazone were compared to cefamandole, cefoxitin, mezlocillin, carbenicillin and amikacin. The minimum inhibitory concentrations of over 500 clinical isolates were determined using the agar dilution method. Moxalactam followed closely by cefoperazone were the most active compounds tested against the enterobacteriaceae. Amikacin was the most active drug against Pseudomonas aeruginosa followed by cefoperazone and moxalactam with 80% of the strains susceptible to 4 mg/1, 8 mg/1, and 16 mg/1 respectively. Cefoperazone was more active than moxalacatam against most of the gram-positive organisms tested. Both cefoperazone and moxalactam were bactericidal against most strains of enterobacteriaceae, Pseudomonas aeruginosa and Staphylococcus aureus .