(537) Comparative Effectiveness of Meropenem/Vaborbactam vs Ceftazidime/Avibactam in Hospital Pneumonia

Introduction: Increasing rates of antimicrobial resistance have complicated the treatment of severe infections. Novel agents with in vitro activity against multi-drug resistant (MDR) gram negative pathogens remain crucial to efforts to address the challenge of antimicrobial resistance. However, few studies explore outcomes with newer agents outside the confines of either randomized trials or small case series.

Methods: To explore comparative effectiveness of meropenem/vaborbactam (MEV) vs. ceftazidime/avibactam (CZA) in pneumonia treatment, we conducted a multicenter retrospective cohort study within the Premier Healthcare Database, 2019-2021. We included all adult hospitalized patients who met previously described criteria for pneumonia and who also received either MEV or CZA. We employed descriptive statistics to compare patients receiving MEV to those receiving CZA along demographic and clinical characteristics. We examined both in-hospital mortality and various measures of morbidity and resource utilization.

Results: We identified 1,546 patients who received MEV or CZA for pneumonia. Compared to those on CZA (n=1,317, 85.7%), MEV patients (n=219, 14.3%) were more likely to be Hispanic (24.75 vs. 15.2%), and more likely to suffer from diabetes with complications (47.5% vs. 38.7%), and obesity (37.0% vs. 27.6%), but less likely to have chronic pulmonary disease (27.9% vs. 36.9%). Subjects receiving MEV more commonly were seen in hospitals in the South (58.5% vs. 45.6%) and less often cared for in teaching institutions (48.9% vs. 60.4%). More MEV than CZA patients required dialysis sometime during hospitalization (14.2% vs. 9.7%). While hospital mortality was similar in the two groups (28.3% vs. 26.5%), we observed a trend towards MEV-treated (vs. CZA-treated) patients having lower mean (SD) post-infection onset unadjusted hospital costs ($139,014 [$172,073] vs. $167,657 [$238,478], p=0.088)

Conclusions: In this cohort of hospitalized patients with pneumonia treated with either MEV or CZA, despite some markers indicating higher disease severity, patients treated with MEV had similar mortality. We observed a trend towards lower hospital costs among MEV treated subjects compared to those receiving CZA.

Disclosure: Study supported by a grant from Melinta Therapeutics, Parsippany, NJ