Utkarsh Goel

Summary: Functional high‐risk (FHR) multiple myeloma (FHRMM) is often defined as progression within 12–24 months of front‐line autologous hematopoietic stem cell transplantation (AHSCT). For patients with early progression after suboptimal front‐line therapies, it is challenging to assign the disease progression to a true FHR phenotype versus less effective front‐line therapy. In this study, we combined data from three Center for International Blood and Marrow Transplant Research studies (MM18‐02, MM19‐01 and MM20‐03). We included patients who received front‐line AHSCT between 2008 and 2018 and had progression n = 465), n = 672) or n = 853) after AHSCT. We classified induction therapy as standard lenalidomide‐containing triplets (bortezomib, lenalidomide, dexamethasone [VRD]/carfilzomib, lenalidomide, dexamethasone [KRD]) versus other (bortezomib, thalidomide, dexamethasone [VTD]/bortezomib, cyclophosphamide, dexamethasone [VCD]/bortezomib, dexamethasone [VD]/lenalidomide, dexamethasone [RD]) and studied the impact of front‐line therapy on post‐FHR overall survival (OS). In the FHR12 cohort (follow‐up 48 months), the OS after VRD/KRD ( n = 238) was 21 versus 17 months with other regimens ( n = 227, hazard ratio [HR] = 1.2, 95% confidence interval [CI]: 0.6–1.06). In a multivariable model, the HR for OS was 0.94 (95% CI: 0.7–1.3, p = 0.69) for VRD/KRD versus other regimens. There was no significant interaction between type of first‐line (1L) therapy and time from 1L AHSCT to first relapse in predicting OS. Similar results were seen for FHR18 and FHR24. FHRMM remains a negative prognostic factor irrespective of front‐line therapy and warrants consideration of T‐cell engagers' second‐line therapy.

Elranatamab, a BCMA-CD3 bispecific antibody, has demonstrated robust activity in relapsed/refractory multiple myeloma (RRMM), but real-world outcomes remain poorly defined. We conducted a multicenter retrospective study of 130 patients treated with commercial elranatamab across nine U.S. academic centers. The cohort was heavily pretreated (91% triple-class refractory, 49% penta-refractory), with 49% previously exposed to BCMA-targeted therapies. Only 22% would have met eligibility for MagnetisMM-3 cohort A. The overall response rate (ORR) was 65%, including ≥CR in 36%. Median progression-free survival (PFS) and overall survival (OS) were 4.3 and 14.6 months, respectively, shorter than MagnetisMM-3. Elevated LDH and low hemoglobin independently predicted poor outcomes and were incorporated into the novel ALPS (Anemia-LDH Prognostic System) score, which stratified patients into distinct risk groups for ORR, OS, PFS, and duration of response. Prior BCMA exposure reduced depth of response, with inferior OS observed in those treated within one year of prior therapy. Infections occurred in 38% of patients. Intravenous immunoglobulin supplementation, modeled as a time-dependent covariate, was associated with improved infection-free survival and PFS. While the incidence of CRS was modestly lower than in MagnetisMM-3, ICANS occurred more frequently in this real-world cohort. These findings highlight the efficacy, limitations, and supportive care needs of elranatamab in a frailer, more heterogeneous real-world RRMM population.

Teclistamab, a bispecific antibody targeting B-cell maturation antigen (BCMA), is effective in relapsed or refractory multiple myeloma (RRMM), but its impact on patients with soft tissue plasmacytomas is unclear. We studied 385 RRMM patients treated with teclistamab at 13 U.S. centers through September 2023, with follow-up to April 2024. Soft tissue plasmacytomas were classified as true extramedullary disease (EMD; not contiguous with bone) or paraskeletal plasmacytomas (PSK; contiguous with bone). Patients with the simultaneous presence of both were classified as true-EMD, reflecting its adverse prognosis. Of those, 109 (28%) had true EMD, 33 (9%) had PSK, and 243 (63%) had no soft tissue plasmacytoma (No-STP). Median follow-up was 9.9 months. Overall response rates were 38% in true-EMD, 54.1% in PSK, and 62.4% in No-STP ( p < 0.001). Median progression-free survival (PFS) was 1.4 months in true-EMD, 6.51 months in PSK, and 8.95 months in No-STP ( p < 0.0001). Median overall survival (OS) was 9.54 months for true EMD, 13.1 months for PSK, and not reached in No-STP ( p = 0.00012). In multivariable analysis, true-EMD was independently associated with inferior PFS and OS, while PSK showed numerically lower outcomes. These findings highlight the need for tailored strategies in patients with soft tissue plasmacytomas, particularly those with true-EMD.

Data describing outcomes of teclistamab in multiple myeloma patients with prior exposure to BCMA-directed therapy (BCMA-DT) are limited. The goal of this multicenter retrospective analysis was to report the efficacy and safety of standard-of-care teclistamab in patients with prior BCMA-DT. A total of 385 patients were included, of whom 193 (50%) had received prior BCMA-DT, including 47 (24%) patients with prior antibody-drug conjugate (ADC)-only, 99 (51%) with chimeric antigen receptor T-cell therapy (CAR T)-only, 36 (19%) with both ADC and CAR T, 6 (3%) with bispecific antibody-only, and 5 (3%) with other combinations. Most safety parameters between cohorts were comparable. The prior BCMA-DT cohort had a lower overall response rate (ORR: 48.7% versus 61.5%; p = 0.012), and median progression-free survival (PFS: 4.6 versus 8.2 months; p = 0.017) compared to the cohort without prior BCMA-DT. However, in multivariable analysis, despite a clear trend, ultimately receipt of a prior BCMA-DT was not independently associated with ORR or PFS (p = 0.057 and p = 0.1, respectively). No significant differences in PFS were noted when stratifying patients by number of prior BCMA-DTs, types of all prior BCMA-DTs received, type of most recent prior BCMA-DT, or depth of response to most recent BCMA-DT. Using the maximally selected rank statistics method, the optimal cut-off for time from the last BCMA-DT exposure to teclistamab initiation was identified as 8.7 months. Patients with >8.7 months between their last exposure to prior BCMA-DT and teclistamab initiation had a significantly improved median PFS with teclistamab (8.1 months, 95% CI: 4.6–11.7) compared to patients with p = 0.001. Altogether, our findings support the use of teclistamab as a viable treatment option in patients previously exposed to BCMA-DT.

Teclistamab, a BCMA-directed bispecific antibody, received regulatory approval for relapsed/refractory multiple myeloma (RRMM) based on the MajesTEC-1 study. Despite the fact that myeloma is primarily a cancer of elderly adults, only 15% of MajesTEC-1 participants (n = 24) were ≥75 years old. In this multicenter retrospective study, we report real-world outcomes of a large cohort of older RRMM patients treated with teclistamab. Of 385 analyzed patients, 83 (22%) were in the older group (age ≥75) and 302 (78%) in the younger group (age p = 0.03) and extramedullary disease (22% vs. 40%, p = 0.02). There were no significant differences in rates of any-grade CRS (52% vs. 59%, p = 0.27), any-grade ICANS (19% vs. 13%, p = 0.12), and overall response rate (62% vs. 53%, p = 0.17) between the older and younger groups. In multivariable analysis, age was not significantly associated with survival outcomes. Our findings suggest that teclistamab is safe and efficacious in well-selected patients ≥75 years old, and advanced age alone should not preclude teclistamab administration.