Health-related quality of life in patients with triple-class exposed relapsed and refractory multiple myeloma treated with idecabtagene vicleucel or standard regimens: patient-reported outcomes from the phase 3, randomised, open-label KarMMa-3 clinical trial

Background: Chimeric antigen receptor T-cell therapy idecabtagene vicleucel (ide-cel) showed significantly improved progression-free survival compared with standard regimens in adults with relapsed and refractory multiple myeloma who had received two to four previous regimens in the ongoing phase 3 KarMMa-3 trial (NCT03651128). This study analysed patient-reported outcomes (PROs), a KarMMa-3 secondary endpoint.

Methods: In the randomised, open-label, phase 3 KarMMa-3 trial, 386 patients in hospitals (≥18 years of age, with measurable disease and an Eastern Cooperative Oncology Group performance status score of 0 or 1, who had received two to four previous regimens-including an immunomodulatory agent, a proteasome inhibitor, and daratumumab-and had documented disease progression after receiving their last dose of the last therapy) were randomly assigned to ide-cel (n=254) or standard regimens (daratumumab, pomalidomide, and dexamethasone; daratumumab, bortezomib, and dexamethasone; ixazomib, lenalidomide, and dexamethasone; carfilzomib and dexamethasone; or elotuzumab, pomalidomide, and dexamethasone; n=132). Patients were expected to complete the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life C30 Questionnaire (QLQ-C30), Multiple Myeloma Module (QLQ-MY20), EQ 5 dimensions (EQ-5D), and EQ-5D visual analogue scale (VAS) at baseline and follow-up timepoints (data cutoff April 18, 2022). PROs included nine prespecified primary domains: EORTC QLQ-C30 GHS-quality of life (QoL), physical functioning, cognitive functioning, fatigue, and pain; QLQ-MY20 disease symptoms and side effects of treatment; and five-level EQ-5D (EQ-5D-5L) index score and EQ-5D visual VAS. Differences in overall least-squares mean changes from baseline to month 20 were analysed using post-hoc constrained longitudinal data analysis. Time to confirmed improvement or deterioration from baseline was analysed using Cox proportional hazard models.

Findings: Patients were randomly assigned between May 6, 2019, and April 8, 2022. Overall, the median age was 63 years (IQR 55-68); 151 (39%) patients were female; and 250 (65%) patients were White, 36 (9%) Black or African American, 19 (5%) Hispanic or Latino, 12 (3%) Asian, and seven (2%) of other race. The median follow-up was 18·6 months (IQR 14·0-26·4). PRO compliance was higher than 75% throughout. Overall least-squares mean changes from baseline favoured ide-cel with Hedges' g effect sizes from 0·3 to 0·7 for most domains. Patients in the ide-cel group showed statistically significant and clinically meaningful improvements across the primary PRO domains of interest, with the exception of QLQ-MY20 disease symptoms, side effects of treatment, and EQ-5D-5L index score, which showed improvement across assessment visits but did not exceed the within-group minimally important difference thresholds. The ide-cel group had shorter times to clinically meaningful improvement than the standard regimens group in QLQ-C30 domains except in role functioning, diarrhoea, and financial difficulties; in QLQ-MY20 domains except body image; and in EQ-5D-VAS.

Interpretation: Ide-cel offers improved health-related quality of life compared with standard regimens for patients with relapsed and refractory multiple myeloma after previous lines of therapy. The PRO data highlight the extended QoL benefits of a one-time infusion with ide-cel compared with continuous treatment with standard regimens in the treatment of triple-class exposed patients with relapsed and refractory multiple myeloma.

Funding: 2seventy bio and Celgene, a Bristol Myers Squibb Company.