Cost-effectiveness of nilotinib versus imatinib as first-line treatment for newly diagnosed patients with Philadelphia chromosome-positive (Ph+) chronic myeloid leukemia in the chronic phase (CML-CP): Swedish perspective.

Abstract

6572 Background: The ENESTnd study showed that, vs. imatinib (400 mg QD), nilotinib (300 mg BID) results in superior major molecular and complete cytogenetic response and time to disease progression as 1st-line (FL) therapy in newly-diagnosed Ph+ CML-CP patients. The objective was to assess, from a Swedish societal perspective, the direct/indirect cost and quality adjusted life years (QALYs) of FL imatinib v. nilotinib in newly-diagnosed Ph+ CML-CP. Methods: A literature-based Markov model was developed to estimate the lifetime QALYs and costs of Ph+ CML-CP patients initiating therapy with nilotinib or imatinib. A central model feature is the discontinuation rate from FL therapy, which was based on ENESTnd for the first 12 months and, thereafter, on the rate observed in the IRIS study, stratified by initial 12-month FL responses. Patients discontinuing FL therapy were modeled to receive one additional tyrosine kinase inhibitor (TKI). Prognosis after FL discontinuation was modeled using published studies. Clinical outcomes and drug exposure were obtained from the ENESTnd study. Non-TKI-drug costs and productivity loss were assumed to increase as disease progressed. Quality of life varied by disease stage and response. Results: Compared to FL imatinib (Table), FL nilotinib results in increases in net discounted FL drug therapy costs, decreases in other direct medical costs and productivity loss, and gains in discounted survival and QALYs. The discounted incremental cost/LY and cost/QALY are estimated at $21,028 and $22,914, respectively. In probabilistic sensitivity analysis, 95% of model replications cost ≤$56,000/QALY gained. Conclusions: FL nilotinib is cost-effective in Swedish patients with Ph+ CML-CP who are initiating TKI therapy. Imatinib Nilotinib Difference FL drug costs* $602,605 $733,924 $131,319 Other direct medical costs* $227,488 $192,521 -$34,968 Productivity* $647,601 $712,079 $64,478 Net cost difference* - - $31,874 Life Expectancy* 17.3 18.82 1.52 QALY* 14.39 15.78 1.39 Cost/LYG* - - $21,028 Cost/QALY* - - $22,914 Notes: US$1=SEK 6.90. * Discounted at 3%/year.