Comparative Effectiveness of Pomalidomide-Based Regimens in Relapsed/Refractory Multiple Myeloma: A Multicenter...

Background: Although multiple pomalidomide-based combinations are active in relapsed and/or refractory multiple myeloma (RRMM), comparative data to guide regimen selection remain limited. Methods: A total of 230 patients with RRMM from 12 centers in China who received pomalidomide-based regimens were included in this retrospective analysis. Overall response rate (ORR) and progression-free survival (PFS) were compared across regimens incorporating bortezomib or ixazomib (V/IPD), carfilzomib (KPD), or daratumumab (DPD), and multivariable analyses were performed to identify prognostic factors. Results: The overall ORR was 73.9%, with rates of 63%, 79%, and 85% in the V/IPD (n = 66), KPD (n = 69), and DPD (n = 95) cohorts, respectively. ORR differed significantly between V/IPD and DPD (p = 0.0165), driven by a higher proportion of ≥VGPR in the DPD group. The median PFS for the entire cohort was 17.4 months (95% CI: 13.7-20.1), compared with 15.4 months (95% CI: 12.8-20.5), 14.2 months (95% CI: 6.9-not estimable), and 19.2 months (95% CI: 15.1-24.9) for V/IPD, KPD, and DPD, respectively, without significant differences. In multivariable analysis, DPD was associated with improved ORR (HR 4.83, p < 0.001) but not with PFS. R-ISS stage III predicted inferior response (HR 0.35, p = 0.04), whereas ≥3 prior lines of therapy correlated with shorter PFS (HR 1.77, p = 0.012). Adverse events were predominantly hematologic, with limited grade 3-4 toxicity and no treatment-related mortality. Conclusions: This multicenter real-world analysis clarifies the relative positioning of commonly used pomalidomide-based regimens in RRMM and underscores the importance of treatment timing and disease stage in optimizing outcomes.