4CPS-029 Cost-effectiveness of eculizumab for active antibody-mediated rejection in early post-kidney transplantation patients

<h3>Background and Importance</h3> The presence of donor-specific antibodies (DSA) is the main cause of the development of acute humoral rejection (AHR), which is associated with a four-fold higher risk of graft loss. Eculizumab is a humanised anti-C5a antibody that inhibits the complement system. <h3>Aim and Objectives</h3> The objective is to evaluate the cost-effectiveness of eculizumab in a cohort of patients with AHR and DSA. <h3>Material and Methods</h3> Patients treated with eculizumab for AHR and DSA since 2016 at a tertiary care hospital. Effectiveness is measured in time free from renal replacement therapy (RRT) after AHR and treatment with eculizumab. The cost is measured as the cost of the medication, and the differential direct healthcare cost between haemodialysis and non-dialysis patients. The price of eculizumab used is the national health system price with VAT, and the direct cost is 144.5€/day (Data from the Renal Anaemia Institute). Descriptive analysis is presented as mean and standard deviation (SD). Inferential analysis was performed using the Kaplan-Meier statistical test. <h3>Results</h3> Nine patients, mean age 49 years (range 22–63 years), 56% women, and with DSA, were treated with eculizumab for AHR. The mean follow-up time was 784 days (112–2364), and the mean cumulative dose of eculizumab was 8633 mg (range 900–33600 mg). The pre-treatment estimated glomerular filtration rate (eGFR), creatinine, and proteinuria were, respectively, 28.3 mL/min/1.73m2 (7–90 mL/min/1.73m2), 4.7 mg/dL (1.4–7.2 mg/dL), and 14763 mg/g creatinine (329.7–111689.1 mg/g creatinine). Post-treatment values (28 days) were 45.3 mL/min/1.73m2 (16–90 mL/min/1.73m2), 1.95 mg/dL (0.8–4.5 mg/dL), and 819.5 mg/g creatinine (59.8–2635.2 mg/g creatinine); and at the end of follow-up, 45.4 mL/min/1.73m2 (16–90 mL/min/1.73m2), 1.99 mg/dL (1.0–6.3 mg/dL), and 576.5 mg/g creatinine (102.3–2621.3 mg/g creatinine). The mean cost of treatment was 94690.7€ (SD, 5484.5–377884.4 €); the mean cost avoided per RRT was 113352.2€ (16184.0–341598.0€), for the actual follow-up time. During the follow-up period, 1/9 patients transitioned to RRT. The estimated mean time free from RRT is 1851.0 days (95% CI, 1140.0–2562.0 days). In inferential estimation, the mean cost avoided per RRT is 267469.5€ (95% CI, 164730–370209.0€). <h3>Conclusion and Relevance</h3> Eculizumab is effective in treating patients with AHR and the presence of DSA. Additionally, it is dominant in the cost-effectiveness analysis (−172778.8€, for 1851.0 days). <h3>References and/or Acknowledgements</h3> <h3>Conflict of Interest</h3> No conflict of interest