Budget impact analysis of the DiviTum®TKa assay in postmenopausal women with hormone receptor positive metastatic breast cancer

Background. DiviTum®TKa, a blood-based biomarker assay developed to monitor and predict treatment response in hormone receptor positive metastatic breast cancer (HR + mBC), may decrease traditional disease monitoring assessments and avoid prolongation of futile treatments.Objective. To estimate the diagnostic and treatment budget impact of the assay on a postmenopausal HR + HER2- mBC population in a one-million-member U.S. health plan.Methods. We developed a budget impact model comparing inclusion and exclusion of DiviTum®TKa to standard care under which DiviTum®TKa 1) reduces the frequency of traditional mBC monitoring tools, and 2) predicts treatment futility in advance of radiological disease progression. Traditional disease monitoring assessment schedules were based on guidelines and expert opinion. DiviTum®TKa's impact on therapy utilization was based on published literature and expert opinion. Modeled costs included DiviTum®TKa, NCCN-recommended treatments, imaging, biomarker testing, and adverse events. We calculated total and per-member per-month (PMPM) costs with a 3-year time horizon.Results. Inclusion of 416 DiviTum®TKa assays ($166,400) was largely offset by 193 fewer CT scans, 88 fewer bone scans, and 55 fewer biomarker tests over 3 years, a savings of -$128,400, resulting in a PMPM of $0.001. In scenario analyses, adding DiviTum®TKa resulted in additional treatment-related cost-savings (-$465,600), resulting in a PMPM cost-savings of -$0.013, or an average savings of -$7,400 per each patient initiating first-line cyclin-dependent kinase 4/6 inhibitor plus aromatase inhibitor therapy. Expected savings approached 3X the spend on the new test. Results were most sensitive to DiviTum®TKa cost, population parameters, and treatment costs.Conclusions. Clinical use of the DiviTum®TKa assay is expected to decrease traditional imaging and monitoring and may reduce the overall cost of managing mBC if it leads to clinical decisions to avoid futile therapy. Post-coverage, real world monitoring of palliative therapies among post-menopausal mBC populations is needed to better categorize cost savings over time.