Clinical efficacy of moxalactam with emphasis on infections due to multidrug-resistant organisms in patients with renal insufficiency.

The efficacy of moxalactam, a new beta-lactam antibiotic with an expanded spectrum of in vitro activity, was evaluated in 22 patients with 27 sites of infection. The pathogens included six strains of multidrug-resistant Serratia marcescens and one of Pseudomonas aeruginosa. The minimal inhibitory concentration of moxalactam for the study isolates ranged from less thant 0.12 to 32 microgram/ml. Peak serum levels exceeded the minimal inhibitory concentration of the pathogen in every instance with mean peak serum levels of 43.0, 65.0 and 123 microgram/ml for doses of 0.5, 1.0 and 2.0 g, respectively. Pharmacokinetic data was obtained in patients with normal and abnormal renal function and during hemodialysis. Moxalactam was found to have excellent penetration into synovial, peritoneal, pleural and cerebrospinal fluids. 23 of the 27 infections were cured, There were six episodes of recurrent infections at the 4-week follow-up among the 12 patients treated for urinary tract infections. Drug toxicity was not a major problem. There were nine instances of superinfection noted (three each due to Candida spp., enterococci and P. aeruginosa), only of which was clinically significant.