Preliminary Cost-Effectiveness of Re-Purposing β-Blockers as an Adjunct Treatment for Women with Triple-Negative Breast Cancer

<b>Background/Objectives:</b> To evaluate the cost-effectiveness of β-blocker use in addition to standard care compared to standard care alone for women with triple-negative breast cancer (TNBC), with effectiveness measured by years of life lived (YLL), quality-adjusted life years (QALYs), and equal-value life years (evLYs) gained. <b>Methods:</b> A population cohort Markov model was developed to compare clinical and economic outcomes for TNBC treated with 1) lifelong β-blocker prescription initiated at diagnosis in addition to standard care versus 2) standard care alone. Life-table modelling was used to capture mortality over a lifetime horizon for the estimated eligible population of Australian women diagnosed with TNBC in 2022 (n = 767). Costs were derived from Australian healthcare perspective, and measured in Australian dollars (AUD) at 2022 prices with 5 percent annual discounting and AUD 28,000 willingness to pay threshold applied. <b>Results:</b> The model estimated 628 (95% CI 139, 1035) YLL, 526 (116, 865) QALYs, and 566 (125, 932) evLYs gained in the β-blocker group compared to standard care. The difference in health costs between β-blocker and standard care groups was AUD -935,116 (-2,365,417, 405,350). The β-blocker intervention was dominant over standard care in terms of both QALYs and evLYs gained. <b>Conclusions:</b> Preliminary modelling suggests that implementing β-blockers as an adjunct pharmacotherapy in the treatment of TNBC was more effective and less costly than current standard care. Further monitoring of long-term outcomes is recommended to validate the findings of observational and preclinical studies, and define the incidence, severity, and cost of β-blocker associated adverse events in cancer populations.