OBJECTIVES: Patients with relapsed or refractory acute myeloid leukemia (R/R AML) have poor health-related quality of life (HRQoL); however, limited evidence is available specifically for FLT3-mutated (FLT3^mut+) R/R AML and health states. To date, the phase 3 ADMIRAL study is the only trial to collect comprehensive EuroQoL 5-Dimension (EQ-5D) data as patients progressed through different health states (eg, event-free survival [EFS], post-event). The objective of this analysis was to estimate utilities for clinically distinct health states in patients with FLT3^mut+ R/R AML, using data from ADMIRAL.

METHODS: In ADMIRAL, EQ-5D utility scores were estimated based on data from all randomized patients (regardless of treatment arm) with a baseline and ≥1 post-baseline assessment. The UK crosswalk value set was used to map 5-level EQ-5D (EQ-5D-5L) to 3-level EQ-5D (EQ-5D-3L) scores. Observed values were used in the analysis without imputation for missing evaluations. Results were estimated at baseline, for patients in the EFS health state following treatment, and patients alive post-event (defined as relapse or treatment failure), using a generalized estimating equation model with a robust variance estimator to account for correlation within patients' repeated assessments.

RESULTS: The analysis included 279 patients with FLT3^mut+ R/R AML (208 gilteritinib; 71 salvage chemotherapy). At baseline, the overall mean EQ-5D-3L score was 0.74 (standard error [SE]=0.01). For patients without hematopoietic stem cell transplantation (HSCT) during follow-up, pre- and post-event utility values were 0.80 (SE=0.02) and 0.70 (SE=0.02), respectively, where higher scores imply better HRQoL. For patients who had undergone HSCT, the pre-event utility was 0.82 (SE=0.03) and the post-event utility was 0.75 (SE=0.03).

CONCLUSIONS: EFS was associated with improved utility scores in patients with FLT3^mut+ R/R AML treated with gilteritinib or salvage chemotherapy for patients both with and without HSCT. Therefore, treatments which prolong patients’ time in a pre-progression state are likely to improve HRQoL.