Health-related quality of life in Chinese multiple myeloma patients treated with daratumumab-based regimens in real world: Exploratory analysis of the MMY4032

Abstract Background: MMY 4032 (ChiCTR2200055491) is a multicenter, non-interventional, observational registry study that evaluated the real-world efficacy and safety of daratumumab-based regimens in Chinese multiple myeloma patients, which enrolled Chinese patients with multiple myeloma (MM) aged ≥18 years and with a history of ≤3 prior lines of therapy prior to initiating daratumumab-based regimens. All patients had either (1) started daratumumab after 1st Aug 2019 and were expected to continue ongoing daratumumab-based therapy at the time of study initiation on 3rd Nov 2021 or (2) started daratumumab after study initiation. Interim analyses of MMY4032 study demonstrated the favorable response and progression-free survival (PFS) without new safety concerns in Chinese patients treated with daratumumab-based regimens (Wang L et al., 2025, BMC Cancer). In the current analysis, health-related quality of life (HRQoL) was assessed. Methods: MMY 4032 enrolled Chinese patients with multiple myeloma (MM) aged ≥18 years and with a history of ≤3 prior lines of therapy prior to initiating daratumumab-based regimens. All patients had either (1) started daratumumab after 1st Aug 2019 and were expected to continue ongoing daratumumab-based therapy at the time of study initiation on 3rd Nov 2021 or (2) started daratumumab after study initiation. In MMY4032, HRQoL was assessed based on European Organization for Research and Treatment of Cancer QoL questionnaire core 30 (EORTC QLQ-C30) and EuroQol 5-Dimension 5-Level (EQ-5D-5L) visual analog scale (VAS). The score range for each scale is from 0 to 100. Higher scores for the functional scales, global health status (GHS) scale, and VAS scale represent better HRQoL, while higher scores on symptom scales indicate worse symptoms. Questionnaires were encouraged to be completed by the patient at each applicable visit. Mixed model for repeated measures (MMRM) model is used to estimate the least square mean (LS mean) changes from baseline on the longitudinal data. Results: The median duration of follow-up from daratumumab initiation to study end was 23.7 months. The LS mean (95% CI) changes from baseline in EQ-5D-5L VAS were -0.1 (95% CI: -3.76 to 3.64; n=42) at Month 4, 4.4 (95% CI: -0.16 to 8.90; n=28) at Month 8, 5.4 (95% CI: 0.14 to 10.61; n=21) at Month 12, 10.2 (95% CI: 2.23 to 18.22; n=9) at Month 18, and 4.0 (95% CI: -3.62 to 11.56; n=10) at Month 24, showing an increasing trend over time until Month 18. As for EORTC QLQ-C30 GHS scale, the same increasing trend could be observed until Month 12, while the LS mean change decreased to -4.3 (95% CI: -14.43 to 5.87; n=9) at Month 18 because 2 out of 9 patients had extremely low scores. The LS mean change from baseline at Month 18 did not meet the clinically meaningful threshold (10 points). Physical and role functioning, disease symptoms including fatigue and pain, remained at baseline levels in two years. Improvements were seen at several time points, for instance, the mean changes of role functioning and fatigue at Month 18 were 15.2 (95% CI: 2.73 to 27.58; n=9) and -20.1 (95% CI: -30.71 to -9.55; n=9), respectively. Conclusion:These results suggested that Chinese MM patients' HRQoL remained stable after treated with daratumumab -based regimens, with improvements observed at several time points in some scales. The results complemented the favorable clinical outcomes observed in Chinese MM patients treated with daratumumab-based regimens in real world, and illustrated the clinical benefits observed were not at the expense of patients' HRQoL, which was consistent with the conclusions of daratumumab related pivotal trials (Terpos E et al., 2022, Am J Hematol; Plesner T et al., 2021, Br J Haematol).