PF735 ECONOMIC MODEL TO EVALUATE THE COST‐EFFECTIVENESS OF SECOND‐LINE NILOTINIB VERSUS DASATINIB FOR THE TREATMENT OF PHILADELPHIA CHROMOSOME‐POSITIVE CHRONIC MYELOID LEUKEMIA (CML‐CP) IN GERMANY

Abstract

Background:For CML‐CP patients who are intolerant or resistant to treatment with imatinib, nilotinib and dasatinib are both second‐generation tyrosine kinase inhibitors (TKIs) that are approved for use after imatinib. With recent label updates and guidelines that are expected to reflect those, there is interest in determining the cost‐effectiveness of second‐line nilotinib and dasatinib with a consideration for treatment‐free remission (TFR) as a recognized treatment goal for patients with deep molecular response. To date, nilotinib is the only TKI on the market with an approved product label for physician‐monitored TFR in select patients.Aims:To develop a cost‐effectiveness model that compares nilotinib with dasatinib in the second‐line treatment setting from the perspective of the German payer.Methods:A partitioned survival model was developed based on a previously published model and progression‐free survival (PFS) and overall survival (OS) curves from a retrospective chart review of patients treated with second‐line nilotinib or dasatinib. The model included health states for second‐line TKI treatment, second‐line TFR, post–second‐line TKI treatment, and accelerated phase (AP)/blast crisis (BC). The analysis was conducted using a lifetime analysis for a cohort of 1,000 adults with CML‐CP requiring second‐line nilotinib or dasatinib.Patients in the model could enter second‐line TFR after 36 months of continuous therapy where the last 12 months were at MR4.5 (BCR‐ABL1 ≤0.0032%). Rates of MR4.5 over time for nilotinib were obtained from the ENESTcmr trial and estimated for dasatinib by applying a hazard ratio derived from a real‐world chart review study of nilotinib and dasatinib. Duration of second‐line TFR based on MR4.5 was based on an extrapolation of the ENESTop trial for nilotinib and the DASFREE trial for dasatinib.The model included monthly recurring costs for drug treatment, resource use (eg, physician visit and BCR‐ABL1 molecular monitoring), and adverse events. Daily dosages for second‐line nilotinib and dasatinib were based on findings from the real‐world chart review. Drug costs were €48.66 per tab (€4,429 per month) for nilotinib and €191.30 per tab (€7,144 per month) for dasatinib. Exploratory analyses of nilotinib at different prices compared with dasatinib were also conducted. All frequency of use estimates and costs were specific to Germany. Health state utility values were derived from a publication. All costs and effects were discounted at 3% per year.Results:The model found that nilotinib was dominant over dasatinib in the second‐line setting. Over the lifetime time horizon, nilotinib was associated with cost savings (‐€88,427), which were mostly due to its lower acquisition cost, more QALYs gained (+2.14), more total life years gained (+2.15), greater years spent in TFR (+1.81), and fewer years in advanced disease (‐0.16). Scenario analyses found that nilotinib remained cost‐effective at a willingness‐to‐pay threshold of €30,000 per QALY when assuming that the cost of nilotinib was increased by up to 80%.Summary/Conclusion:Results from the model analysis indicated that nilotinib is expected to demonstrate cost‐effectiveness compared with dasatinib, resulting from greater molecular response and more patient years on TFR, combined with a lower cost of drug treatment. The superior efficacy of nilotinib and the associated differences in TFR could offset the lower unit cost for generic dasatinib.