Improvement of Patient-Reported Outcomes Among Heavily Pretreated Patients with Lower-Risk Myelodysplastic Syndromes and High Transfusion Burden Treated with Imetelstat on the IMerge Phase 3 Trial

Abstract

CONCLUSIONS Transfusion-dependent anemia and related fatigue are commonly associated with lower-risk myelodysplastic syndromes (LR-MDS) and frequently not improved with therapy. Patients with symptoms associated with anemia have an impaired quality of life and inferior overall survival. In IMerge (NCT02598661), the phase 3, randomized, global trial of patients with LR-MDS and a red blood cell transfusion burden of ≥4 U, imetelstat-treated patients had a significantly higher transfusion independence rate than those treated with placebo and showed sustained improvement in patient-reported fatigue via the Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue (Sekeres et al. EHA 2023. P732). Here, we assess the impact of imetelstat on several patient-reported outcomes (PROs) relevant to LR-MDS. Functional Assessment of Cancer Therapy-Anemia (FACT-An; 55 items) and Quality of Life in Myelodysplasia Scale (QUALMS; 38 items) were the main questionnaires used. Analyses included symptom-specific derived scores for the following parameters: dyspnea, measured by 1 FACT-An and 1 QUALMS item; physical function and systemic symptoms, by 3 FACT-An items each; pain, by 2 FACT-An items; and bleeding, by 1 QUALMS item. Higher scores indicated improvement. QUALMS total score and physical burden score were also analyzed. Psychometric analyses were conducted using blinded interim data to document the measurement properties of these item sets and define the scores that would be used to specify PRO end points in IMerge; all analyses were exploratory and were conducted in the intention-to-treat (ITT) population. The overall effect of imetelstat on each score was evaluated from the repeated measurement mixed model (RMMM) comparing the least-squares means (LSMs) of change in score estimated in the 2 treatment groups using all available data while on treatment up to cycle 30. A positive mean change in the dyspnea score was observed throughout the treatment, up to cycle 24, in the imetelstat group but not in the placebo group (Figure). The RMMM analysis showed an overall change in dyspnea score from baseline of 0.53 (by LSM with 95% CI, 0.241-0.825) with imetelstat versus −0.40 (by LSM with 95% CI, −0.794 to 0.003) with placebo, with a significant difference between the treatment groups (LSM difference, 0.93; 95% CI, 0.446-1.411; P < .001; Table). The model-based mean change estimates for each score showed that, despite having high transfusion burden at baseline, patients in the imetelstat group did not experience more deterioration in any of the other outcomes than those in the placebo group (Table). In addition, the QUALMS composite scores suggested significantly improved health outcomes with imetelstat versus placebo based on RMMM. LSM difference was 4.66 (95%CI, 0.862-8.461; P = .016) and 6.34 (95% CI, 1.771-10.913; P = .007) for QUALMS total and QUALMS physical burden, respectively (Table). Findings from multiple validated PRO questionnaires consistently show that patients with red blood cell transfusion-dependent LR-MDS enrolled into the IMerge randomized trial who were treated with imetelstat reported improved fatigue, dyspnea, and QUALMS composite scores (total and physical burden) compared with those in the placebo group. These data indicate that, in addition to improving transfusion burden in patients with LR-MDS, imetelstat targets multiple core symptoms of LR-MDS simultaneously, also improving PROs.