OBJECTIVES

: This study compares cost-effectiveness (CE) results when using data from the initial and latest database locks (DBLs) of CheckMate 025 (NCT01668784), a randomized phase 3 trial investigating nivolumab versus everolimus in pre-treated aRCC. The minimum follow-up was 14 months (initial) and 64 months (latest) in these DBLs, respectively.

METHODS

: We developed a 3-state (progression-free, progressive disease and death) partitioned survival model to evaluate the CE of nivolumab versus everolimus from a United States payer perspective, with a 25-year time horizon and 3% discounting for costs (2020 US$) and outcomes. Key trial data inputs from the DBLs were progression-free survival (PFS), overall survival (OS), time-to-treatment discontinuation (TTD), treatment response, patient utilities, and subsequent systemic treatment. For comparison, only the inputs derived from the trial were changed in this analysis.

RESULTS

: Using longer term data resulted in a modest reduction in the incremental cost-utility ratio (ICUR) for nivolumab versus everolimus ($70,490/QALY [incremental cost-effectiveness ratio (ICER): $54,240/LY] versus $72,389/QALY [$55,946/LY] using the initial DBL). The initial DBL had the same (best-fitting) functional forms for survival extrapolations as the latest DBL but underestimated incremental LY and QALY gains with nivolumab by 11.4% and 11.0%, respectively. Based on OS extrapolations from the initial DBL, total LYs for nivolumab and everolimus were 3.1% and 0.6% lower, respectively. Changes in incremental costs (+8.6% with latest DBL) were mainly driven by differences in the use of subsequent treatment and the types of agents given between the two DBLs. Health state utility values, treatment response, and TTD curves between DBLs had limited ICUR influence.

CONCLUSIONS

: The initial DBL conservatively underestimated the incremental lifetime survival benefit for nivolumab versus everolimus when compared with estimates using the latest DBL from CheckMate 025. Higher total incremental costs observed with longer follow-up were offset by increased LY and QALY gains between DBLs.