Cost-Effectiveness of Dostarlimab for Advanced or Recurrent MSI-H/dMMR Endometrial Cancer in Anti-PD1/PD-L1 Naïve Patients: A Taiwan's National Health Insurance Perspective
Author(s)
Hsiao-Tung Tsai, MS, PharmD1, Chi-Yun Wu, PhD2, Liang-Yi Lin, PhD2, Yao-Chun Wen, MSc3, Yi Wen Chang, MD4, Chyong-Huey Lai, MD5, Shih-Tsung Huang, PhD1, Fei-Yuan Sharon Hsiao, PhD6.
1Department of Pharmacy, National Yang Ming Chiao Tung University, Taipei, Taiwan, 2Graduate Institute of Clinical Pharmacy, College of Medicine, National Taiwan University, Taipei, Taiwan, 3Market Access Manager, GSK Far East B.V., Taipei, Taiwan, 4GSK Far East B.V., Taipei, Taiwan, 5Gynecologic Cancer Research Center, Chang Gung Memorial Hospital, Linkou Branch, Taoyuan, Taiwan, 6Department of Pharmacy, Graduate Institute of Clinical Pharmacy, College of Medicine, National Taiwan University, Taipei, Taiwan.
1Department of Pharmacy, National Yang Ming Chiao Tung University, Taipei, Taiwan, 2Graduate Institute of Clinical Pharmacy, College of Medicine, National Taiwan University, Taipei, Taiwan, 3Market Access Manager, GSK Far East B.V., Taipei, Taiwan, 4GSK Far East B.V., Taipei, Taiwan, 5Gynecologic Cancer Research Center, Chang Gung Memorial Hospital, Linkou Branch, Taoyuan, Taiwan, 6Department of Pharmacy, Graduate Institute of Clinical Pharmacy, College of Medicine, National Taiwan University, Taipei, Taiwan.
OBJECTIVES: Dostarlimab monotherapy has demonstrated significant clinical benefits in patients with advanced or recurrent endometrial cancer, particularly in those with microsatellite instability-high (MSI-H) or mismatch repair-deficient (dMMR) tumors in GARNET trial. This study aims to evaluates the cost-effectiveness of dostarlimab for PD-L1 naïve patients with MSI-H/dMMR advanced or recurrent endometrial cancer who have progressed after platinum-based chemotherapy, from the perspective of Taiwan’s National Health Insurance (NHI).
METHODS: A partitioned survival model with three state (progression-free survival, progressed disease, and death states) was developed to assess the cost-effectiveness of the dostarlimab monotherapy. The model incorporates a 3-week cycle length for a lifetime time horizon of 40 years. The main efficacy parameters were derived from the GARNET trial (cut-off date as November, 2021), with comparator treatment effectiveness estimated through matching-adjusted indirect comparisons (MAICs). Comparator treatment for base case analysis was carboplatin + paclitaxel (CP). Costs parameters, including direct medical costs, were derived from local price lists, published literature, and expert opinions. Quality-adjusted life years (QALYs) were calculated based on utility values from EQ-5D-5L data in the GARNET study. The incremental cost-effectiveness ratio (ICER) was calculated using a 3.5% discount rate and a willingness-to-pay threshold (WTP) of TWD3,300,000 (three times Taiwan's per capita GDP in 2024). Probabilistic sensitivity analyses would be further conducted.
RESULTS: In the base case analysis, the incremental cost of dostarlimab over carboplatin + paclitaxel was NT$6,830,333, corresponding to an incremental gain of 2.3 QALYs in the intention-to-treat cohort. The incremental cost-effectiveness ratio (ICER) is NT$3,003,713 per QALY gained. Deterministic sensitivity analyses reveals that patient baseline utility had the greatest influence on the ICER.
CONCLUSIONS: Dostarlimab monotherapy is cost-effective for PD-L1 naïve patients with advanced or recurrent MSI-H/dMMR endometrial cancer compared to carboplatin + paclitaxel (CP), based on a WTP threshold of TWD3,300,000 per QALY.
METHODS: A partitioned survival model with three state (progression-free survival, progressed disease, and death states) was developed to assess the cost-effectiveness of the dostarlimab monotherapy. The model incorporates a 3-week cycle length for a lifetime time horizon of 40 years. The main efficacy parameters were derived from the GARNET trial (cut-off date as November, 2021), with comparator treatment effectiveness estimated through matching-adjusted indirect comparisons (MAICs). Comparator treatment for base case analysis was carboplatin + paclitaxel (CP). Costs parameters, including direct medical costs, were derived from local price lists, published literature, and expert opinions. Quality-adjusted life years (QALYs) were calculated based on utility values from EQ-5D-5L data in the GARNET study. The incremental cost-effectiveness ratio (ICER) was calculated using a 3.5% discount rate and a willingness-to-pay threshold (WTP) of TWD3,300,000 (three times Taiwan's per capita GDP in 2024). Probabilistic sensitivity analyses would be further conducted.
RESULTS: In the base case analysis, the incremental cost of dostarlimab over carboplatin + paclitaxel was NT$6,830,333, corresponding to an incremental gain of 2.3 QALYs in the intention-to-treat cohort. The incremental cost-effectiveness ratio (ICER) is NT$3,003,713 per QALY gained. Deterministic sensitivity analyses reveals that patient baseline utility had the greatest influence on the ICER.
CONCLUSIONS: Dostarlimab monotherapy is cost-effective for PD-L1 naïve patients with advanced or recurrent MSI-H/dMMR endometrial cancer compared to carboplatin + paclitaxel (CP), based on a WTP threshold of TWD3,300,000 per QALY.
Conference/Value in Health Info
2025-09, ISPOR Real-World Evidence Summit 2025, Tokyo, Japan
Value in Health Regional, Volume 49S (September 2025)
Code
RWD293
Topic Subcategory
Health & Insurance Records Systems
Disease
SDC: Oncology