Cost and resource utilisation for liquid biopsy vs tissue biopsy genotyping in advanced NSCLC: A micro-costing model.

1542 Background: For patients with advanced non-small cell lung cancer, tumour genotyping identifies actionable variants that inform targeted therapeutic choices, that improve outcomes. Liquid biopsy genotyping (LBG) is a non-invasive approach to tissue biopsy genotyping (TBG) that reduces turnaround, avoids repeat tissue biopsy, and can identify additional actionable variants. However, despite these benefits, patient access to LBG is not universal in a range of healthcare systems. While others have developed models evaluating the cost-effectiveness of LBG, these have are limited by assumptions regarding frequency of oncogenic variants and treatment utilisation. We utilised a micro-costing model (MCM) to quantify the cost/resources of LBG and TBG in a prospective trial ( PLAN; ClinicalTrials.gov Identifier: NCT05542485) aimed at investigating the feasibility of LBG in a tertiary cancer centre. Methods: A deterministic MCM was developed to enumerate the cost to generate a genomics report for both LBG and TBG in NSCLC. Capital costs were calculated based on up-front investment and annual depreciation/maintenance. Costs of consumables and staff time associated with each procedure was sourced from relevant hospital departments (e.g. Medical Physics) and evaluated for accuracy by a health economist and medical oncologist. We calculated the cost of sample acquisition (endobronchial ultrasound-guided biopsy or phlebotomy), processing, and genotyping for both LBG and TBG, from patients enrolled on the PLAN study (n = 100) between 08/2023-07/2024. Finally, we performed an exploratory analysis investigating potential reduction in staff time associated with automated library preparation, using currently available technology. Results: We identified that TBG requires more staff time (€534 vs €330), capital investment (€326 vs €16), and consumables (€1544 vs €788), resulting in an overall increased cost, compared with LBG (€2404 vs €1135). Automation of library preparation would reduce staff time required for LBG (Reduced to €191; 33% reduction) with less of an impact on TBG (Reduced to €485; 10% reduction). This difference was due to the increased wet-lab time with LBG and greater staff time for sample acquisition in TBG vs LBG (€298 vs €8). Finally, in the PLAN study, LBG resulted in cancellation of 12 repeat tissue biopsies, resulting in further savings. Conclusions: LBG is a cheaper alternative to TBG. Our data indicates LBG saves cost in the areas of healthcare staffing and capital infrastructure with further savings made through avoidance of repeat tissue biopsies. Thus, the resources required for LBG and TBG are different and should be considered in service planning for tumour types such as NSCLC in which genotyping is standard-of-care. Clinical trial information: NCT05542485 .