Neither aducanumab nor donanemab is cost-effective in treating adults with early Alzheimer disease

Reference

Ross EL, Weinberg MS, Arnold SE. Cost-effectiveness of aducanumab and donanemab for early Alzheimer disease in the US. JAMA Neurol 2022;79(5):478-487.

Synopsis

These authors developed a decision analytic model, including various estimates of harms and benefits of therapy and their associated economic costs, to determine if either aducanumab or donanemab are cost-effective in treating adults with early Alzheimer disease. These anti-amyloid monoclonal antibodies are the furthest developed agents in this class. The authors used published or publicly available data to feed the model, including the “utilities” associated with different degrees of cognitive impairment, and then conducted sensitivity analyses to determine the robustness of their findings. Additionally, they projected the effectiveness of these agents on quality-adjusted life years (QALYs) from the scores reported in individual studies. Since these are messy, the authors conducted a more optimistic sensitivity analysis. Finally, they used US$150,000/QALY as the threshold for determining cost-effectiveness. Lifetime QALYs increased by 0.133 with aducanumab and 0.408 with donanemab. Despite optimistic estimates of treatment effectiveness, the authors concluded that neither of these agents is cost-effective. We recently reviewed the only data published so far on aducanumab, which was not at all encouraging. Since cost-effectiveness is a ratio, a small number, especially a 0, in the denominator makes for a very expensive intervention!