OBJECTIVES: New antibiotics are often costlier and offer marginal or no significant clinical advantages over existing alternatives. This study compared the cost-effectiveness of cefiderocol and imipenem/cilastatin in treating complicated urinary tract infections (cUTI) in hospitalized patients and estimated the ICER.

METHODS: We conducted a cost-effectiveness analysis from the perspective of the payer using data from various sources: clinical cure outcomes from the FDA website, the average sales price from CMS, life expectancy data from the CDC, hospital costs from the American Hospital Association, the consumer price index for hospital care from the US Bureau of Labor Statistics, and cUTI survival and quality of life data from the published literature. The analysis focused on direct healthcare costs and included health outcomes clinical cure rate and quality-adjusted life years (QALYs). Costs were converted in 2023 constant dollars. The costs and outcomes were not discounted. A multivariate sensitivity analysis using Monte Carlo simulation was also performed.

RESULTS: Cefiderocol was more expensive than imipenem/cilastatin ($22,537 vs. $13,934), primarily due to its higher average drug cost ($9,648 vs. $683). While cefiderocol showed slightly better clinical cure rates (89.7% vs. 87.4%) and similar QALYs (0.830 vs. 0.829) to those of imipenem/cilastatin the difference was not clinically or statistically significant. The additional cost with cefiderocol was $374,032 per case cured and $8.2 million per QALY gained (assuming a life expectancy of 12.2 at an average age of 75.1 years) compared to imipenem/cilastatin. The sensitivity analysis showed that it is highly unlikely that cefiderocol ICER would be below the willingness to pay threshold of $75,000-$100,000.

CONCLUSIONS: Cefiderocol was more expensive and similar outcomes compared to imipenem/cilastatin. Imipenem/cilastatin is a more cost-effective option for treating complicated urinary tract infections in hospitalized patients. The incremental cost-effectiveness ratio per QALY gained with cefiderocol over imipenem/cilastatin exceeded the commonly referenced willingness to pay societal thresholds.