A real-world investigation into prescribing patterns and effectiveness of ceftolozane/tazobactam among critically ill patients from SPECTRA

Background: Ceftolozane/tazobactam (C/T) real-world use was examined in a global population of critical care patients treated in intensive care unit settings. Methods: The Study of Prescribing patterns and Effectiveness of Ceftolozane/Tazobactam Real-world Analysis (SPECTRA) is a multinational, retrospective observational study of 617 adults treated with C/T conducted between 2016 and 2020. Population-associated clinical, treatment-related, and microbiologic characteristics, resource utilization, and clinical outcomes were assessed in critical care patients. Results: In this SPECTRA critical care cohort (n=298), 81.5% had ≥1 comorbidity. Common infection sites were respiratory (50.0%), skin/wound/tissue (21.1%), blood (13.7%), and urine (10.3%); common pathogens were Pseudomonas aeruginosa (89.7%; 66.7% multidrug resistant), Klebsiella spp. (6.9%), and Escherichia coli (6.4%); 51.7% received C/T as third-line/salvage therapy. Thirty-day readmission rates were 3.4% (all cause) and 1.7% (infection related). Overall clinical success was 53.4% (95% confidence interval: 47.5% to 59.1%) and was greater with first-line C/T (62.2%) versus third line (45.5%). All-cause in-hospital mortality was 35.6%; infection-related mortality was 13.8%. Conclusions: In this multinational, high-risk cohort, most patients had beneficial outcomes despite their clinical complexity and late intervention with C/T. These results support C/T use against a wide range of Gram-negative pathogens in critical care settings. Trial registration: Not applicable due to retrospective design.