(HealthDay)—Plazomicin is noninferior to meropenem for patients with complicated urinary tract infections (UTIs), according to a study and a research letter published in the Feb. 21 issue of the New England Journal of Medicine.

Florian M.E. Wagenlehner, M.D., from Justus Liebig University in Giessen, Germany, and colleagues randomly assigned 609 patients with complicated UTIs, including acute pyelonephritis, to receive intravenous plazomicin or meropenem for a total of seven to 10 days of treatment. The researchers found that with respect to the primary efficacy end point (composite cure, including clinical cure and microbial eradication), plazomicin was noninferior to meropenem. Composite cure was observed in 88.0 and 91.4 percent of patients in the plazomicin and meropenem groups, respectively, on day 5. At the test-of-cure visit (15 to 19 days after therapy initiation), 81.7 and 70.1 percent of patients, respectively, had composite cure.

In a related research letter, James A. McKinnell, M.D., from Los Angeles Biomedical Research Institute, and colleagues randomly assigned patients with bloodstream infection or hospital-acquired or ventilator-associated bacterial pneumonia caused by carbapenem-resistant Enterobacteriaceae infections to plazomicin (18 patients) or colistin (21 patients) combined with adjunctive meropenem or tigecycline. Due to slow enrollment, the trial was stopped early. The researchers found that the primary end-point event (death from any cause at 28 days or clinically significant disease-related complications) occurred in 24 and 50 percent of receiving plazomicin and colistin, respectively.

"Establishing a successful environment of antibacterial drug development will require that further scientific, logistic, and be addressed in order to have ongoing development to meet patient needs," write the authors of an accompanying editorial.

Several authors from both studies disclosed financial ties to , including Achaogen, which manufactures plazomicin and funded both studies.