Cost-effectiveness of sunitinib as second-line treatment for gastrointestinal stromal tumor in the People’s Republic of China

Abstract

Cost-effectiveness of sunitinib as second-line treatment for gastrointestinal stromal tumor in the People’s Republic of China Jian Li,1 Hong Ye Ren,2 Juanjuan Zhang,2 Peng Dong,2 Yan Wang,3 Andrea L Stevens,3 Yi Han,3 Min Huang4 1Laboratory of Carcinogenesis and Translational Research for the Ministry of National Education, Department of GI Oncology, Peking University School of Oncology, Beijing Cancer Hospital & Institute, 2Pfizer Inc., Beijing, People’s Republic of China; 3WG Consulting, New York, NY, USA; 4School of Pharmacy, Sun Yat-sen University, Guangzhou, Guangdong, People’s Republic of China Objective: To evaluate the cost-effectiveness of sunitinib as a second-line treatment in patients with advanced gastrointestinal stromal tumors that no longer respond to imatinib 400 mg/d, compared with imatinib 600 mg/d, 800 mg/d, or best supportive care (BSC) in the People’s Republic of China. Methods: This study was conducted from the government payer’s perspective with a time horizon of 5 years. Three health states were considered: progression-free survival, disease progression survival, and death, with a cycle length of 6 weeks. Probabilities of disease progression and death were estimated based on survival functions using exponential distribution and progression survival data in the clinical trials. Drug costs were based on drug retail prices and the patient assistance program in the People’s Republic of China, and adverse event management costs were based on published data and/or expert opinion. Uncertainties for parameters in the study were addressed through one-way deterministic and probabilistic sensitivity analysis. Results: When sunitinib was compared with imatinib 600 mg/d and BSC, the incremental cost-effectiveness ratio was RMB75,715 with RMB121,080 per quality-adjusted life-year (QALY) gained. Sunitinib demonstrated lower costs and higher QALYs than imatinib 800 mg/d. In the probabilistic sensitivity analysis, the willingness-to-pay per QALY gained was set to be three times the per capita gross domestic product of the People’s Republic of China, that is, RMB46,510 in 2014. Sunitinib was demonstrated to be cost-effective compared with imatinib 600 mg/d, imatinib 800 mg/d, and BSC, with probabilities of 82.3%, 95.6%, and 78.2%, respectively. Limitations: Clinical data for imatinib 800 mg/d and BSC in the analysis were based upon studies in non-Chinese populations. Because of the unavailability of utility data from Chinese gastrointestinal stromal tumor patients, the analysis used the utility estimates from studies performed in other countries. Conclusion: Sunitinib provides greater clinical benefit than high-dose imatinib or BSC as a second-line treatment. In the Chinese setting, sunitinib is estimated to be cost-effective compared with imatinib 800 mg/d, imatinib 600 mg/d, or BSC. Keywords: cost-effectiveness analysis, gastrointestinal stromal tumor, imatinib, sunitinib, best supportive care, second-line