Lifetime Cost-Utility Analysis of Emicizumab Prophylaxis in Severe Haemophilia A Without Inhibitors in China: A Markov Model Analysis.

AIM: As emicizumab shares no sequence homology with factor VIII (FVIII), in patients with haemophilia A, haemostasis can be restored irrespective of the presence of FVIII inhibitors. Emicizumab, therefore, substantially improved previously available prophylactic options. This study aims to evaluate the cost-effectiveness of using emicizumab prophylaxis therapy compared to recombinant FVIII (rFVIII) prophylaxis for the treatment of severe haemophilia A.

METHODS

A Markov model from a Chinese healthcare system perspective using annual cycles was constructed to evaluate the lifelong costs and effectiveness. All patients started at age zero in a non-inhibitor state, treated with either emicizumab or rFVIII prophylaxis. On-demand rFVIII was given upon breakthrough bleeding for both groups. A part of severe patients developed FVIII inhibitors resulting from on-demand treatment. For patients with inhibitors, those previously treated with rFVIII prophylaxis switched to a recombinant activated factor VII (rFVIIa) on-demand only therapy, whereas those previously on emicizumab kept the same prophylactic regimen with rFVIIa for breakthrough bleeds. One immune tolerance induction (ITI) was allowed to eradicate inhibitors. Model inputs, including utility values, bleeding rates, adverse event rates and the success rate of ITI were from HAVEN 1 and 3 trials and the other literature.

RESULTS

The results of both the 0-12 age group and lifetime simulations demonstrated a dominant economic advantage of emicizumab prophylaxis over rFVIII prophylaxis therapy.

CONCLUSION

Severe haemophilia A patients treated by emicizumab prophylaxis can benefit both patients' QoL and economic outcomes compared to those treated by rFVIII prophylaxis.