Androgen receptor inhibitor double therapies in the management of metastatic castration-sensitive prostate cancer: a cost-effectiveness analysis

Aims To evaluate the cost-effectiveness of darolutamide plus androgen deprivation therapy (DARO+ADT) versus enzalutamide plus ADT (ENZA+ADT) and apalutamide plus ADT (APA+ADT) as first-line androgen receptor pathway inhibitor (ARPI) double therapies for metastatic castration-sensitive prostate cancer (mCSPC) from a US healthcare sector perspective.Methods A partitioned survival model with three health states (progression-free mCSPC, progressed mCRPC, and death) projected lifetime costs and outcomes over a 30-year horizon with monthly cycles. DARO+ADT efficacy was derived from the ARANOTE trial; comparative efficacy for ENZA+ADT and APA+ADT was estimated via network meta-analysis-derived hazard ratios. Costs (drug acquisition, adverse event management, subsequent therapy, end-of-life care) and utilities were derived from trial data, published literature, and US cost sources. Costs and outcomes were discounted at 3% annually. Deterministic, probabilistic, and two-way sensitivity analyses assessed parameter uncertainty at a willingness-to-pay threshold of $150,000/QALY.Results DARO+ADT generated 4.18 QALYs versus 4.03 (ENZA+ADT) and 3.99 (APA+ADT), driven by longer treatment persistence and lower adverse-event-related disutility. Versus ENZA+ADT, DARO+ADT yielded 0.15 incremental QALYs at $12,564 incremental cost (ICER: $85,108/QALY; net monetary benefit: $9,579). Versus APA+ADT, DARO+ADT was dominant (0.19 additional QALYs, $4,293 lower cost; net monetary benefit: $33,153). Two-way sensitivity analyses varying off-treatment utilities and post-discontinuation therapy costs showed that DARO+ADT remained cost-effective versus ENZA+ADT and dominant versus APA+ADT, respectively, across the parameter ranges tested. Probabilistic sensitivity analysis showed DARO+ADT was cost-effective in 51% and 52% of simulations versus ENZA+ADT and APA+ADT, respectively, which demonstrates uncertainty around the incremental findings.Limitations The analysis relies on indirect comparisons and extrapolated modeling, factors that may limit the generalizability of the findings.Conclusions DARO+ADT was cost-effective versus ENZA+ADT and dominant versus APA+ADT, driven by improved tolerability and treatment persistence, supporting its value as a first-line mCSPC option.