Cost-Effectiveness Analysis of Ceftazidime-Avibactam Versus Colistin-Meropenem in the Treatment of Infections Due to Carbapenem-Resistant Enterobacteriaceae in Colombia

Abstract Background: Ceftazidime-Avibactam (CAZ-AVI) may offer a significant advance over previously antimicrobials against carbapenem-resistant Enterobacteriaceae (CRE). We evaluate the cost-effectiveness of CAZ-AVI compared to colistin-meropenem (COL+MEM) in the treatment of CRE infections in ColombiaMethods: A decision tree model was developed from healthcare system perspective assuming a 30-day time horizon. Inputs were derived from a published observational study. The clinical course was simulated based on treatment response between 48-72 hours, and the duration of the treatment was 7-14 days. The clinical failure was assumed as the addition of an antibiotic. The model considered that combination therapy of COL+MEM was not superior to monotherapy to reflect real clinical behavior. Cost inputs were extracted from a published Colombian manual tariffs and official databases, expressed in 2019 dollars (USD). Utility values were from published literature. The sensitivity analyses were performed.Results: In the base case analysis, CAZ-AVI was associated with reduced mortality, length of hospital stay and fewer add-on antibiotics, resulting in an increase of 1.76 QALYs per patient versus COL+MEM. and incremental costs associated in CAZ-AVI were $2,521 higher per patient compared to COL+MEM ($755 versus $3,276). The incremental costs were partially increased due to the lower mortality rate observed with CAZ-AVI. The incremental cost-effectiveness ratio was estimated to be $3,317 per QALY. In the probabilistic sensitivity analysis, with a willingness to pay above $2,438, CAZ-AVI has a higher probability of being cost-effective.Discussion: CAZ-AVI demonstrates cost-effectiveness as a treatment for CRE infections by reducing the number of deaths and increasing QALYs.