Cost-effectiveness of biomarker-based and universal strategies for the treatment of advanced-stage endometrial cancer

Objective: To compare cost-effectiveness of targeted therapeutic strategies for non-Hispanic Black (NHB) and non-Hispanic White (NHB) patients with newly diagnosed, advanced-stage endometrial cancer. Methods: A Markov-based cost-utility model using a third-party payer perspective compared concurrent and maintenance treatment strategies incorporating dostarlimab and trastuzumab for newly diagnosed stage III–IV endometrial cancer: chemotherapy alone; 3 universal immunotherapy strategies (universal concurrent and maintenance dostarlimab +/− trastuzumab for HER2/neu-positive serous and/or carcinosarcomas); and 3 targeted immunotherapy strategies (dostarlimab for mismatch repair deficient (dMMR) tumors +/− trastuzumab for HER2/neu positive serous and/or carcinosarcomas). Costs (2024 USD), utilities, and clinical estimates were derived from published literature and the National Cancer Database. The base case analysis was a microsimulation with 10,000 runs, accompanied by a Monte Carlo probabilistic sensitivity analysis with 20,000 trials. Cost-effectiveness was assessed using incremental cost-effectiveness ratios (ICERs) with a willingness-to-pay threshold of $150,000/quality-adjusted life year (QALY). We performed one-way and two-way sensitivity analyses on key parameters and analyses stratified by race/ethnicity. Results: All targeted immunotherapy strategies were cost-effective compared to chemotherapy alone in both NHB and NHW, while universal immunotherapy was never cost-effective. Targeted strategies were more cost-effective in NHB than NHW. Targeted dostarlimab for dMMR plus trastuzumab for HER2 serous and carcinosarcomas was the most cost-effective strategy compared to chemotherapy, with an ICER of $119,945/QALY. In sensitivity analysis, assuming longer durations of treatment benefit resulted in lower ICERs. Conclusions: Personalized treatment strategies incorporating HER2 and MMR testing should be considered to optimize both cost-effectiveness and equity in care.