Background and hypothesis Atypical haemolytic uraemic syndrome (aHUS) is a rare condition caused by compliment dysregulation. Eculizumab is an effective treatment for patients with aHUS, yet a lifelong treatment strategy is costly for health services and is of uncertain additional benefit to patients. This economic evaluation was conducted as part of stopping eculizumab treatment safely in aHUS (SETS aHUS) trial and assessed the cost-effectiveness of a lifelong delivery of eculizumab strategy compared with stopping treatment with a disease monitoring strategy over the long-term.

Methods A Markov model was used to estimate cost and quality adjusted life years (QALYs) for the two strategies compared. The main source of data used was SETS aHUS, for quality-of-life, resource use estimates, and treatment probabilities. Time to treatment restart over an estimated patient lifetime was extrapolated from trial data using parametric survival functions.

Results The eculizumab withdrawal and disease monitoring strategy changed QALYs by 0.22 (95% CrI: −0.7 to 1.25), and reduced costs per patient by £4 188 361 (95% CrI: -£6 390 713 to -£675 511) compared with the lifelong delivery of eculizumab. Survival was similar, with withdrawal patients presenting 0.0005 LYs less on average (95% CrI: −0.003 to 0) over an 80-year time horizon. The likelihood of withdrawal being more effective and less costly was 71%. Results were robust across multiple scenarios exploring uncertainties.

Conclusion Treatment withdrawal with disease monitoring strategy is cost-effective compared with lifelong treatment with eculizumab. Its adoption is expected to substantially reduce costs per patient and may improve patient quality of life on average.

The authors have declared no competing interest.

This project was funded by the National Institute for Health and Care Research; Health Technology Assessment programme (project number 15/130/94).

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Ethical approval was obtained from the North East Tyne & Wear South Research Ethics Committee, Reference 18/NE/0078, on 13th of April 2018

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