OBJECTIVES: To assess the cost-effectiveness of using FoundationOne Liquid CDx (F1LCDx) in liquid biopsy compared to no-molecular diagnosis (no-mDx) among patients with advanced non-small cell lung cancer (NSCLC) where a tissue diagnosis is not possible, from the perspective of the Spanish National Health System.

METHODS: A joint model (decision-tree and partitioned-survival models) was developed to compare both costs and effects of performing a molecular diagnostic from a liquid biopsy with F1LCDx versus no-mDx over a lifetime horizon, so a 3% discount rate was applied for both cost and health outcomes. Treatment and utilities data were obtained from the literature and survival curves were extrapolated using exponential models. Only direct costs were considered (€2023). All the assumptions and inputs used in the model were validated by a panel of 11 oncologists from different Spanish centers. To assess uncertainty, several sensitivity analyses were performed.

RESULTS: In a hypothetical cohort of 1,000 patients with advanced NSCLC in whom tissue-based testing cannot be performed, if F1LCDx is used in liquid biopsy 392 oncogenic biomarker alterations would be detected, 166 patients could receive reimbursed targeted therapies and 53 patients could be enrolled in clinical trials. No alterations are found if no-mDx is done. Over the lifetime horizon, using F1LCDx in the 1,000-patients cohort resulted in a gain in quality-adjusted life-years (QALYs) of 360.54 and in 449.48 life years (LYs), while it involved an incremental cost of 13,237,529€. Therefore, the resulting ratios were 36,716€ per QALY gained and 29,451€ per LY gained. Sensitivity analyses were consistent with the base case results.

CONCLUSIONS: In patients where it is not possible to obtain a tissue sample, molecular diagnosis is not available at initiation of treatment. Our analysis shows that using F1LCDx in these patients is a cost-effective strategy in Spain.