Cost-effectiveness of frontline eltrombopag with immunosuppressive therapy for severe aplastic anemia

• Frontline eltrombopag plus immunosuppressive therapy (IST) is cost-effective compared with IST alone for adults with severe aplastic anemia • Incremental net monetary benefit per patient treated with frontline eltrombopag is, on average, 64, 000 The randomized phase 3 RACE trial demonstrated eltrombopag used in conjunction with traditional immunosuppressive therapy (IST) to be an efficacious treatment for severe aplastic anemia. However, eltrombopag can pose a significant cost burden. Using clinical data from the RACE trial, we performed the first cost-effectiveness analysis of frontline eltrombopag plus IST in adults with newly diagnosed severe aplastic anemia across all accepted willingness-to-pay (WTP) thresholds from the United States modified societal perspective. The primary outcome was the incremental net monetary benefit across WTP thresholds of 50, 000-150, 000/quality-adjusted life year (QALY) with base-case WTP threshold of 120, 000/QALY. Frontline eltrombopag plus IST versus frontline IST alone accrued discounted costs of 593, 000 and 561, 000, and discounted QALYs of 11. 53 and 10. 73, respectively, with a per-patient incremental net monetary benefit of 64, 000 95% credible interval -91, 000 to 262, 000 favoring frontline eltrombopag plus IST. Deterministic sensitivity analyses demonstrated that the 6-month overall response risk ratio (with versus without frontline eltrombopag) had the greatest effect on model results. In probabilistic sensitivity analysis, frontline eltrombopag with IST was favored in 78% of 10, 000 second-order Monte Carlo iterations, as well as 58% and 82% of 10, 000 iterations at WTPs of 50, 000 and 150, 000/QALY, respectively. At current pricing, frontline eltrombopag is the cost-effective therapeutic strategy in adults with severe aplastic anemia in the US. Longer-term clinical and patient utility data will likely help further clarify the cost-effectiveness of eltrombopag in this setting.