Hughes, David

PURPOSE This analysis aimed to contextualize the symptoms of peripheral neuropathy (PN) experienced by patients with triple-class refractory (TCR) multiple myeloma (MM) treated with elranatamab in the MagnetisMM-3 clinical trial with those experienced by patients with TCR MM receiving a new line of physician's choice of therapy in the real-world MagnetisMM-14 study. METHODS MagnetisMM-3 included 123 patients and MagnetisMM-14 included 35 who had TCR MM and were enrolled under the same eligibility criteria. Patient-reported symptoms of PN were collected monthly using the Chemotherapy-Induced Peripheral Neuropathy-20 item (CIPN20) questionnaire and compared for clinically meaningful differences across sensory, motor, and autonomic domains. Higher scores indicated worse patient-reported PN symptoms. RESULTS Baseline demographics and clinical characteristics for patients in MagnetisMM-3 and MagnetisMM-14 were generally similar. Patients in MagnetisMM-3 had a median of five ( v four in MagnetisMM-14) prior lines of therapy. In MagnetisMM-14, common index therapies included elotuzumab + pomalidomide (23%), carfilzomib + pomalidomide (19%), or carfilzomib + cyclophosphamide (19%), all with corticosteroids. Mean scores for sensory (15.8 v 14.8) and motor (14.4 v 12.2) domains of the CIPN20 were similar between MagnetisMM-3 and MagnetisMM-14 at baseline. Mean scores for the autonomic domain were 14.0 versus 21.3 at baseline, respectively. No clinically meaningful differences for any domain were found between month 6 scores or changes in scores from baseline to month 6 between MagnetisMM-3 and MagnetisMM-14 populations. CONCLUSION These findings suggest that elranatamab treatment was not associated with a worsening of patient-reported PN symptoms across the sensory, motor, and autonomic domains of the CIPN20. Moreover, PN symptoms reported with elranatamab treatment were similar to those reported with other common therapies used in real-world clinical practice for the management of MM. MagnetisMM-3 ClinicalTrials.gov identifier: NCT04649359 .

BACKGROUND Several studies have highlighted the poor clinical outcomes observed among patients with relapsed/refractory multiple myeloma (MM), particularly those with triple-class refractory (TCR; refractory to at least one protease inhibitor [PI], one immunomodulatory drug [IMiD], and one anti-CD38 monoclonal antibody [mAb]) disease. The aim of this study was to describe the longitudinal changes in quality of life (QOL) and other patient-reported outcomes (PROs) among TCR MM patients who initiated a new line of therapy in real-world clinical practice. METHODS A prospective, multi-site observational study was conducted through the Mayo Clinic system. Patients with TCR MM initiating a new line of therapy (defined as the index date) were followed for a 12-month observation period. For patients initiating a CAR-T therapy, PRO survey assessments were conducted at apheresis, lymphodepletion chemotherapy, and every month after T-cell infusion until Month 6. All other patients received a survey assessment before index and every month thereafter until Month 6. PRO measures included the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30; including the Global Health Score [GHS]), the EORTC Multiple Myeloma Questionnaire (QLQ-MY20; including the Disease Symptoms [DS] domain score), the EORTC QLQ for Chemotherapy-Induced Peripheral Neuropathy (CIPN20), the EuroQoL-5 Dimensions (EQ-5D), the Patient Global Impression of Severity (PGIS), and the Patient Global Impression of Change (PGIC). PRO surveys were supplemented with retrospective chart reviews conducted at 3 months and 12 months following the index date to obtain clinical information. Descriptive data were reported at each timepoint separately for patients who received CAR-T and non-CAR-T index therapies. The study is ongoing and this abstract reflects all patient data collected as of May 2024. RESULTS This interim analysis included 77 patients (58% male, 95% White, mean age 66 years). The median time interval between becoming TCR and the index date was 5.6 months (interquartile range [IQR]: 1.8, 18.2). Most patients had an Eastern Cooperative Oncology Group (ECOG) score of 0 or 1 (48% and 45%, respectively) and were Revised International Staging System (R-ISS) I or II (27% and 36%, respectively); 42% of patients had high-risk cytogenetics and 14% had extramedullary disease. The median (IQR) number of prior treatment lines was 4 (4, 5). Forty-two patients initiated a CAR-T therapy as their index therapy (12 and 30 treated with ide-cel and cilta-cel, respectively); the remaining 35 patients predominantly initiated a treatment regimen containing an IMiD (51%), a PI (54%), an anti-CD38 antibody (40%), or an alkylating agent (37%). Among these non-CAR-T patients, common regimens used were pomalidomide + elotuzumab + corticosteroids (26%), carfilzomib + cyclophosphamide + corticosteroids (20%), and pomalidomide + carfilzomib + corticosteroids (17%). Among CAR-T patients, QOL generally remained stable from apheresis (mean GHS and EQ-5D VAS were 62.3 and 66.4, respectively) to lymphodepletion (61.2 and 65.9) to Month 6 (64.2 and 68.9). Disease symptoms improved (mean DS domain scores at apheresis, lymphodepletion, and Month 6 were 25.7, 24.1, and 20.1, respectively) though pain, specifically, plateaued/worsened (mean pain domain scores were 24.5, 32.1, and 32.6). Based on the PGIC, 76% of patients reported being “a little better” or “much better” as early as Month 1, which stabilized over time (75% at Month 6). Among non-CAR-T patients, QOL largely remained stable (GHS and EQ-5D VAS was 62.9 and 68.4, respectively, at baseline and 64.9 and 67.7 at Month 6), though disease symptoms, including pain, improved over time (DS was 28.0 at baseline and 22.8 at Month 6; pain was 40.8 at baseline and 28.1 at Month 6). Based on the PGIC, 30.7% of patients reported being “a little better” or “much better” at Month 1, which improved to 52.7% by Month 6. CONCLUSIONS In this interim analysis of an ongoing prospective observational study, baseline values suggest a significant QOL burden among TCR patients. QOL generally remained stable for both CAR-T and non-CAR-T patients over the first several months post-therapy with some select improvements in disease symptoms. However, the patients (particularly CAR-T patients) directly reported some holistic improvement based on the PGIC as early as Month 1.