Cost-effectiveness analysis of emicizumab use in hospitalized older individuals with acquired hemophilia A.

Acquired hemophilia A (AHA) is a rare, autoimmune disease that leads to a severe bleeding diathesis. The efficacy of emicizumab use in the inpatient management of AHA has been recognized, but widespread inpatient use remains limited due to its high cost. To evaluate cost-effectiveness of up-front emicizumab use in the inpatient management of AHA in the United States, we built a Markov simulation to examine the cost-effectiveness of administering emicizumab with concurrent recombinant activated factor VII (rFVIIa) vs rFVIIa alone (standard of care [SOC]) in older individuals newly diagnosed with AHA and hospitalized for bleeding control. Model outcomes included direct costs (medication use and hospital stay) and utilities associated with bleeding and nonbleeding health states (measured using quality-adjusted life days [QALDs]). The analysis was conducted over a 20-day hospitalization horizon with a health system perspective. We conducted deterministic and probabilistic sensitivity analyses (PSA), capturing uncertainty across parameters over 10 000 Monte Carlo simulations. The addition of up-front emicizumab to SOC vs SOC alone yielded lower total direct cost ($248 934 vs $569 038) and more QALDs (15.92 vs 14.72). The addition of up-front emicizumab to SOC was the dominant strategy. The duration of daily rFVIIa use had the largest impact on the incremental net monetary benefit. In a PSA, emicizumab was cost-effective in 100% of simulations. The addition of up-front emicizumab to SOC is less costly and more effective, even at current emicizumab pricing. Our results provide strong economic and clinical justification to consider up-front emicizumab use in AHA management.