OBJECTIVES : To evaluate the cost-effectiveness of nivolumab versus taxane-based chemotherapy (TbC) for previously treated advanced esophageal squamous cell carcinoma (aESCC) patients from a United States (US) payer perspective using data with minimum 36-months follow-up from the ATTRACTION-3 trial.

METHODS : A partitioned survival model, consisting of progression-free, progressed disease and death health states was developed to evaluate the total costs and quality-adjusted life-years (QALYs) over a 20-year time horizon. Health state occupancy was estimated using an area under-the-curve approach and extrapolating PFS and OS Kaplan-Meier curves using parametric survival functions suggested by NICE technical support document 14 and splines. Total QALYs were estimated via treatment-specific time-to-death (TTD)-based utilities which were derived from the trial’s EQ-5D data. Costs components included in the model were drug acquisition and administration, subsequent therapies, adverse events, routine disease management and terminal care. Treatment-related costs were calculated by jointly utilizing toxicity-related discontinuation rates and PFS. Scenario analyses included re-parameterizing the model with treatment-specific progression-based health state utilities and calculating treatment-related costs based on extrapolated duration of treatment (DoT) curves from the trial to account for the possibility of post-progression treatment.

RESULTS : Treatment with nivolumab resulted in $65,000 incremental costs and 0.45 incremental QALYs versus TbC with a corresponding incremental cost-utility ratio (ICUR) of $143,400/QALY. While adopting progression-based health state utilities and DoT curves to calculate treatment-related costs raised the ICURs by $8,000/QALY and by $34,500/QALY, respectively, the resulting ICURs remained below a willingness-to-pay threshold of $195,000/QALY which approximately corresponds to three times the US gross domestic product per capita per WHO benchmark. QALY differential between nivolumab and TbC was minimally sensitive to the health-utilities when they were treatment-specific throughout the entire time-horizon.

CONCLUSIONS : In the US, nivolumab can be a life-extending and cost-effective treatment option for aESCC intolerant to previous chemotherapy at conventional willingness-to-pay thresholds.