OBJECTIVES: Carbapenem-resistant Acinetobacter baumannii (CRAB) infections present a critical public health challenge in the United States, demanding effective treatment strategies due to limited options and significant healthcare burdens. This study aimed to assess the cost-difference and cost-effectiveness of sulbactam-durlobactam compared to colistin in managing CRAB infections in the critical care setting.

METHODS: A decision-analytic model was developed to evaluate treatments used in the Acinetobacter Treatment Trial Against Colistin (ATTACK) trial, in which patients received either sulbactam-durlobactam or colistin alongside imipenem-cilastatin for 7-14 days, followed by 14±2 days of follow-up. The model incorporated survival, CRAB recurrence, and the incidence of acute kidney injury (AKI), which is higher for patients treated with colistin. Costs were adjusted to 2023 US dollars. We performed a deterministic sensitivity analysis for key input parameters and a scenario analysis that assumed patients with recurrence switched to cefiderocol.

RESULTS: In the base case analysis, the expected per-patient cost, including expenses for medication and managing AKI, was $21,981 for sulbactam-durlobactam versus $8,002 for colistin. The incremental cost-effectiveness ratio (ICER) for sulbactam-durlobactam compared to colistin was $107,529 per additional life saved. Variations in sulbactam-durlobactam treatment cost notably influenced the cost-effectiveness ratio ($64,560-$164,821 per additional life saved). The model was less sensitive to variation in the survival rate without recurrence ($94,891-$120,168 per additional life saved) and the incidence of AKI injury in colistin-treated patients ($101,158-$113,753 per additional life saved). In the scenario analysis, the overall cost difference was larger ($31,596 for sulbactam-durlobactam versus $10,013 for colistin), yielding an ICER of $166,022 per additional life saved.

CONCLUSIONS: Although medication costs were higher for sulbactam-durlobactam compared with colistin, the cost difference lessened when including the acute costs of managing nephrotoxicity. Incorporating the efficacy difference observed in the ATTACK trial yielded a cost-effectiveness ratio of $107,529 per additional life saved.