Comparative Efficacy of Ciltacabtagene Autoleucel Versus Standard-of-Care Treatments for Patients with Previously Treated Relapsed or Refractory Multiple Myeloma: A Matching-Adjusted Indirect Comparison

Introduction: Matching adjusted indirect comparisons (MAICs) were performed to compare the efficacy of cilta-cel versus elotuzumab + pomalidomide + dexamethasone (EloPd), isatuximab + carfilzomib + dexamethasone (IsaKd), isatuximab + pomalidomide + dexamethasone (IsaPd), and selinexor + bortezomib + dexamethasone (SVd) in patients with relapsed or refractory multiple myeloma (RRMM) who have received at least one prior therapy and are lenalidomide-refractory. Methods: Unanchored MAICs were performed using individual patient-level data (IPD) for all apheresed patients randomized to the cilta-cel arm of CARTITUDE-4 (n = 208) and published arm-level data for EloPd from ELOQUENT-3 (n = 60), IsaKd from IKEMA (lenalidomide-refractory subgroup, n = 57), IsaPd from ICARIA-MM (n = 154), and SVd from BOSTON (lenalidomide-refractory subgroup, n = 53). Eligibility criteria from each comparator trial were applied to the cilta-cel arm IPD, and further imbalances in patient characteristics were adjusted by weighting the cilta-cel patient data to match the reported baseline characteristics of the comparator trials. Comparative efficacy was estimated for overall response rate, very good partial response or better (≥ VGPR) rate, complete response or better (≥ CR) rate, progression-free survival (PFS), and overall survival (OS). Results: After adjustment, cilta-cel patients were significantly more likely to achieve an overall response versus EloPd, IsaPd, and SVd, and were significantly more likely to achieve ≥ VGPR and ≥ CR versus all comparators. Cilta-cel patients also had significant reductions in the risk of disease progression or death (PFS) versus all comparators: 64% versus EloPd, 49% versus IsaKd, 69% versus IsaPd, and 62% versus SVd. Similarly, cilta-cel patients had significant improvements in OS for all feasible comparisons: 52% versus EloPd, 58% versus IsaPd, and 60% versus SVd. Conclusion: Cilta-cel patients demonstrated clinically meaningful benefits over EloPd, IsaKd, IsaPd, and SVd for response and survival outcomes, highlighting its superiority over alternative treatment options for patients with RRMM who have received at least one prior therapy and are refractory to lenalidomide.