Sorafenib Versus Axitinib for Second-Line Treatment of Sunitinib-Refractory Patients with Advanced Renal Cell Carcinoma (RCC) in the United States (US)

ABSTRACT Introduction A Phase III randomized trial, AXIS, investigated the efficacy and safety of axitinib (Inlyta®) versus sorafenib (Nexavar®), oral targeted therapies licensed in the US for the treatment of advanced RCC. The objective of this study was to conduct an economic evaluation of sorafenib versus axitinib in 2nd-line, sunitinib-refractory patients with advanced RCC from a US perspective. Methods A survival partition model with 3 health states (progression-free, post-progression and death) was constructed to estimate the direct lifetime medical costs and clinical outcomes for a patient starting in the 2nd-line from a US third-party payer perspective. Patients were apportioned into health states based on overall survival and progression-free survival Kaplan-Meier curves from the AXIS trial. Patients were assumed to receive cancer medication until progression and best supportive care thereafter. Utility values and medical resource use were based on literature. Adverse event rates and management were informed by the AXIS trial and clinical expert opinion, respectively. Model outcomes included total costs, life-years (LYs) and quality-adjusted life-years (QALYs), all discounted at 3% per year. Probabilistic sensitivity analysis (PSA) evaluated the model's robustness. Results Total per-patient costs were estimated to be $127,808 for sorafenib and $159,800 for axitinib. The cost difference of $31,992 was mainly attributable to higher cost of axitinib compared to sorafenib. Model results suggested that sorafenib and axitinib provide similar benefit in terms of LYs and QALYs: sorafenib provided an average of 1.440 LYs and 1.016 QALYs and axitinib provided an average of 1.423 LYs and 1.015 QALYs per patient. The lower total per-patient cost for sorafenib versus axitinib finding persisted in the PSA, with 95% of iterations resulting in an incremental cost difference between $9,000 and $63,000. Conclusions Results of this modeling study suggest that, for the 2nd-line, sunitinib-refractory patients with advanced RCC in the US, treatment with sorafenib is a less expensive alternative to axitinib that provides similar benefit in terms of LYs and QALYs. Disclosure I. Ozer-Stillman: This research is sponsored by Bayer HealthCare R. Keyser: This research is sponsored by Bayer HealthCare A. Ambavane: This research is sponsored by Bayer HealthCare P. Cislo: Employed by Bayer HealthCare