Estimating the Lifetime Survival and QALYs of Tumor-Treating Fields in Combination With Temozolomide for Glioblastoma Using a Korean Population
Author(s)
Jorge F. Nino de Rivera Guzman, MSc1, Junmin Park, MSc2, Bruce Wang, PhD3.
1Health Economy specialist, Novocure, Glendale, CO, USA, 2Novocure, Tokyo, Japan, 3Novocure, Portsmouth, NH, USA.
1Health Economy specialist, Novocure, Glendale, CO, USA, 2Novocure, Tokyo, Japan, 3Novocure, Portsmouth, NH, USA.
OBJECTIVES: This analysis evaluates the survival and quality-of-life benefits of Tumor-Treating Fields (TTFields) in combination with temozolomide (TMZ) for Korean patients with glioblastoma (GBM). Using data from the Korean subgroup of the EF-14 trial, we estimate life years (LYs) and quality-adjusted life years (QALYs) to assess the impact of TTFields + TMZ on patient outcomes.
METHODS: A partitioned survival model was used to estimate LYs and QALYs for TTFields + TMZ versus TMZ monotherapy over a 40-year horizon. Survival projections followed a three-phase approach. For years 1-5, Kaplan-Meier data from the South Korean EF-14 subgroup were used covering the first 2.8 years for TTFields + TMZ and 2.5 years for TMZ, supplemented by EF-14 overall data. For years 5-15, a conditional survival approach was applied, while years 15-40 used Korean life tables. Utility values were sourced from the literature, and sensitivity analyses were conducted to assess variations in survival and utility estimates.
RESULTS: TTFields + TMZ resulted in a life expectancy of 3.55 LYs compared to 2.04 LYs for TMZ monotherapy, yielding an incremental gain of 1.51 Lys. Regarding QALYS, TTFields + TMZ provided 2.72 versus 1.59 for TMZ alone, an incremental increase of 1.13 QALYs. Sensitivity analyses identified the utility of progressed disease as key driver of QALY variation.
CONCLUSIONS: This analysis of the Korean GBM population showed that combining TTFields with TMZ resulted in greater LYs and QALYs compared to TMZ monotherapy. The improvements in survival and quality-adjusted life expectancy exceeded those reported in previous studies, where TTFields added 1.25 LYs and 0.96 QALYs. These findings suggest that TTFields may provide even greater benefits in certain populations, reinforcing its potential to enhance both survival and quality of life for GBM patients.
METHODS: A partitioned survival model was used to estimate LYs and QALYs for TTFields + TMZ versus TMZ monotherapy over a 40-year horizon. Survival projections followed a three-phase approach. For years 1-5, Kaplan-Meier data from the South Korean EF-14 subgroup were used covering the first 2.8 years for TTFields + TMZ and 2.5 years for TMZ, supplemented by EF-14 overall data. For years 5-15, a conditional survival approach was applied, while years 15-40 used Korean life tables. Utility values were sourced from the literature, and sensitivity analyses were conducted to assess variations in survival and utility estimates.
RESULTS: TTFields + TMZ resulted in a life expectancy of 3.55 LYs compared to 2.04 LYs for TMZ monotherapy, yielding an incremental gain of 1.51 Lys. Regarding QALYS, TTFields + TMZ provided 2.72 versus 1.59 for TMZ alone, an incremental increase of 1.13 QALYs. Sensitivity analyses identified the utility of progressed disease as key driver of QALY variation.
CONCLUSIONS: This analysis of the Korean GBM population showed that combining TTFields with TMZ resulted in greater LYs and QALYs compared to TMZ monotherapy. The improvements in survival and quality-adjusted life expectancy exceeded those reported in previous studies, where TTFields added 1.25 LYs and 0.96 QALYs. These findings suggest that TTFields may provide even greater benefits in certain populations, reinforcing its potential to enhance both survival and quality of life for GBM patients.
Conference/Value in Health Info
2025-09, ISPOR Real-World Evidence Summit 2025, Tokyo, Japan
Value in Health Regional, Volume 49S (September 2025)
Code
RWD90
Topic Subcategory
Health & Insurance Records Systems
Disease
SDC: Oncology