Presentation (CTI)

OBJECTIVES: Prostate cancer is a major health concern among men in the U.S. Approximately 24.6% of metastatic castration-resistant prostate cancer (mCRPC) patients have homologous recombination repair (HRR) gene alterations. HRR-deficient patients have shown improved survival with poly (ADP-ribose) polymerase (PARP) inhibitors. This study evaluates the cost-effectiveness of talazoparib plus enzalutamide in HRR-deficient mCRPC patients from the U.S. payer perspective.
METHODS: A partitioned survival model was developed to simulate the progression of HRR-deficient mCRPC patients. The model estimated the proportion of patients in three health states: progression-free, post-progression, and death. Two treatment strategies were evaluated: 1) Talazoparib plus enzalutamide and 2) Enzalutamide. The time horizon for the model was 10 years, with monthly cycles to estimate long-term outcomes including direct medical costs, life-years (LYs), and quality-adjusted life years (QALYs). Clinical data were derived from the TALAPRO-2 clinical trial. Utility values were adjusted for treatment-related serious adverse events (SAEs) and incorporated into the model to calculate the expected QALYs. Direct medical costs were estimated from the U.S. payer perspective and adjusted to year 2024 U.S. dollars. One-way (OWSA) and probabilistic sensitivity analysis (PSA) were performed to test the robustness of the base-case results.
RESULTS: In the base-case analysis, the total direct cost was US$665,360 and 2.0703 QALYs were gained in the enzalutamide strategy. The talazoparib plus enzalutamide strategy incurred an incremental cost of US$488,106 with an additional 0.7017 QALYs, resulting in an ICER of US$695,566 per QALY (exceeded WTP threshold of US$100,000 per QALY). OWSA found that the combination therapy strategy would be cost-effective if talazoparib cost decreased by 92%. PSA indicated that enzalutamide was preferred with 100% probability.
CONCLUSIONS: Talazoparib plus enzalutamide was not accepted as cost-effective when comparing to enzalutamide alone for HRR-deficient mCRPC patients from a U.S. payer perspective.