Health-Related Quality of Life in Patients with Relapsed/Refractory Multiple Myeloma Treated with Talquetamab, a G Protein-Coupled Receptor Family C Group 5 Member D x CD3 Bispecific Antibody: Patient-Reported Outcomes from MonumenTAL-1

Abstract

Introduction: Studies of multiple myeloma (MM) populations indicate that patients with more advanced and heavily pretreated disease have worse health-related quality of life (HRQoL) than those at earlier stages. In addition, treatment options are limited for triple-class exposed relapsed/refractory MM (RRMM), with little hope of improving HRQoL. Talquetamab is a first-in-class, off-the-shelf, T-cell redirecting bispecific antibody targeting both GPRC5D and CD3 receptors. MonumenTAL-1 is a phase 1/2 trial (NCT03399799/NCT04634552) of talquetamab in patients with RRMM. Patient-reported outcomes (PROs) data on HRQoL, symptoms, and functioning were collected in the phase 2 cohorts of MonumenTAL-1. Here, we report PROs, focusing on global health status (GHS), physical functioning, pain, and fatigue, for the 0.4 mg/kg subcutaneous (SC) weekly (QW) cohort. Data for the 0.8 mg/kg SC every 2 weeks (Q2W) cohort are immature currently. Methods. Patients enrolled in phase 2 must have previously received ≥3 prior lines of therapy, including ≥1 proteosome inhibitor, ≥1 immunomodulatory drug, and ≥1 anti-CD38 monoclonal antibody (ie, triple-class exposed). After screening, patients received talquetamab step-up doses, requiring hospitalization, before cycle 1. The European Organization for Research and Treatment of Cancer Quality of Life Core 30-item (EORTC QLQ-C30) questionnaire is a cancer-specific PRO instrument administered at screening, cycle 1, and then every other cycle. It includes a subscale to measure HRQoL, 5 functional scales, 3 symptom subscales, and 6 additional single items. Scores range from 0 to 100; higher scores indicate better GHS and functioning, whereas a higher score represents more symptom severity. Compliance with PROs was calculated as the number of completed assessments divided by the number of patients on study treatment at each assessment time point. Treatment effect was assessed with a mixed-effects model with repeated measures. For the analysis of the proportion of patients with meaningful improvement, the threshold for meaningful improvement from baseline was defined as a change of ≥10 points. Time to worsening was determined using the Kaplan-Meier estimate. Results: For patients treated with 0.4 mg/kg SC QW (n=122), compliance with completing the EORTC QLQ-C30 was 96% at screening and over 80% at most post-treatment visits. After an immediate decline in overall HRQoL between screening and cycle 1, patients reported meaningful improvements in EORTC QLQ-C30 GHS and a meaningful reduction in pain symptoms compared with baseline (Figure). Least squares [LS] mean change for fatigue symptoms was -8 (95% CI, -13.83, -2.26) at cycle 9 and reached a mean decrease (ie, improvement) of 11.2 points (95% CI, -18.9, -3.53) at cycle 13. Similar results were observed in the physical (LS mean change at cycle 9: 6.5 [95% CI, 2.05, 10.93]) and role (LS mean change at cycle 9: 11.4 [95% CI, 4.55, 18.25]) functioning subscales. With treatment, the proportion of patients with meaningful improvement was high; for example, at cycle 9 for the 0.4 mg/kg cohort, 42% improved in GHS, 34% in physical functioning, 40% in role functioning, 86% in pain symptoms, and 78% in fatigue symptoms. Median time to worsening ranged from 2 (role and social functioning) to 9 months (nausea/vomiting). Overall, changes in PROs were similar in the 0.8 mg/kg SC Q2W cohort in early cycles, but conclusions are limited due to short follow-up and small sample size. The 0.8 mg/kg SC Q2W cohort will be updated with additional follow-up. Conclusions: With talquetamab treatment, patients in the 0.4 mg/kg SC QW cohort reported improvement in overall HRQoL and physical and role functioning and a decrease in pain and fatigue. These findings are consistent with the clinical benefits of talquetamab as demonstrated by the efficacy results from the MonumenTAL-1 study. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal