Economic evaluations of sunitinib versus interferon-alfa (IFN-α) in first-line metastatic renal cell carcinoma (mRCC)

Abstract

6607 Background: A randomized phase III trial of sunitinib vs. IFN-a as first-line therapy for patients with mRCC is ongoing. An interim analysis of this study demonstrated superiority for the primary endpoint, progression-free survival (PFS), in the sunitinib arm vs. the IFN-a arm (median PFS = 11 months [95% CI: 10–12] vs. 4 months [95% CI: 4–6]; P<0.000001). Because of the clinical significance of these results, the objective of this study was to demonstrate the economic value of sunitinib vs. IFN-a in this setting from a US third-party payer perspective. Methods: Two Markov models with a 5- and 10-year time horizon were developed to evaluate the cost- effectiveness of sunitinib vs. IFN-a. The models projected survival and costs in 6-week cycles based on extrapolation of the trial survival data. Model 1 looked at first-line treatment followed by palliative care only, while Model 2 incorporated second-line treatment. Effectiveness was measured in terms of progression-free months (PFM) in Model 1, and life-years (LY) gained and quality adjusted life-years (QALY) gained in Model 2. Resource utilization included drugs, tests, scans, monitoring, physician visits, hospitalizations and treatment of adverse events. Costs and survival benefits were discounted annually at 3% and 5% in Model 1 and 2, respectively. All costs were adjusted to 2006 US dollars. Scenario and probabilistic sensitivity analyses were conducted. Results: Projected PFS and overall survival were longer for sunitinib than for IFN-a. The incremental cost-effectiveness ratios of sunitinib vs. IFN-a over 5- and 10-years were $7,769 and $7,782/PFM, respectively, in Model 1. Model 2 results at 10 years were $67,215/LY and $52,593/QALY gained. The key drivers of the model results were survival and sunitinib drug costs. Both models were robust in the tested scenarios. Conclusions: Both analyses found that sunitinib is a cost-effective alternative to IFN-a as first-line treatment in mRCC, with cost-effectiveness ratios within the established threshold that society is willing to pay for health benefits (i.e. $50,000–100,000/LY or QALY). No significant financial relationships to disclose.