Elranatamab Plus Iberdomide Combination Achieves 95.5% Response Rate in Relapsed/Refractory Multiple Myeloma
核心洞察
The combination of elranatamab and iberdomide demonstrated a 95.5% objective response rate with a 45.5% complete response rate in BCMA (搜索)-naive patients with relapsed/refractory multiple myeloma (搜索) in the phase 1b MagnetisMM-30 trial.
Responses occurred rapidly with a median time to response of 1.4 months, and the safety profile was manageable with expected toxicities including neutropenia (搜索), infections, and low-grade cytokine release syndrome (搜索).
Real-world data from 130 patients showed elranatamab maintains meaningful activity in heavily pretreated populations, with a 65% overall response rate despite less favorable baseline characteristics compared to clinical trials.
The combination of elranatamab-bcmm (搜索) (Elrexfio) and iberdomide (CC-220) achieved a remarkable 95.5% objective response rate in patients with relapsed or refractory multiple myeloma (搜索), according to early data from the phase 1b MagnetisMM-30 trial presented at the 2025 ASH Annual Meeting. The doublet demonstrated rapid and deep responses with a manageable safety profile in BCMA (搜索)-naive patients who had received 2 to 4 prior lines of therapy.
Impressive Response Rates Across Dose Levels
At a median follow-up of 7.8 months, the combination induced an objective response rate (ORR) of 95.5% (95% CI, 77.2%-99.9%) in all evaluable patients (n = 22), which included a complete response (CR) or better rate of 45.5% and a very good partial response (VGPR) or better rate of 77.3%. Responses occurred early, with a median time to response of 1.4 months (range, 0.5-2.7).
The efficacy was consistent across different dose levels. Patients receiving elranatamab at 76 mg once weekly plus 1.0 mg of iberdomide (DL1; n = 13) achieved an ORR of 92.3% (95% CI, 64.0%-99.8%) with a CR or better rate of 46.2%. Those given elranatamab at 76 mg once every 2 weeks plus 1.0 mg of iberdomide (DL-1; n = 9) achieved a 100.0% ORR (95% CI, 66.4%-100.0%) with 44.4% experiencing a CR or better.
When examined by cytogenetic risk, patients with standard risk (n = 11) experienced a confirmed ORR of 100% (95% CI, 71.5%-100.0%), while those with high cytogenetic risk (n = 9) achieved an ORR of 88.9% (95% CI, 51.8%-99.7%).
Manageable Safety Profile with Expected Toxicities
The safety profile aligned with known toxicities of the individual agents. In evaluable patients (n = 17), 4 dose-limiting toxicities (DLTs) were observed: 2 at DL1 (grade 3 anorexia and grade 4 neutropenia (搜索)) and 2 at DL-1 (grade 3 febrile neutropenia and grade 4 neutropenia).
The most common treatment-emergent adverse effects included neutropenia (搜索) (77.3%), cytokine release syndrome (搜索) (CRS) (68.2%), and infections (40.9%). Notably, most infections were grade 2 or lower, as were all cases of CRS and immune effector cell-associated neurotoxicity syndrome (搜索) (ICANS).
"The data demonstrate that the combination of elranatamab and iberdomide is effective and manageable in BCMA (搜索)-naive patients with relapsed/refractory multiple myeloma (搜索)," said Attaya Suvannasankha, MD, of Melvin and Bren Simon Comprehensive Cancer Center (搜索), Indiana University. "Even with a median follow-up of just 7.8 months, the overall response rate of 95.5% and CR rate or better rate of 45.5% appears to favorably compare with the single-agent outcomes in a different population, as well as also some emerging combinations with CELMoDs."
Scientific Rationale for Combination Approach
The combination strategy is based on complementary mechanisms of action. Elranatamab is a bispecific BCMA (搜索)-directed CD3 (搜索) T-cell engager that received FDA accelerated approval in August 2023 for patients with relapsed or refractory multiple myeloma (搜索) who have received at least 4 prior lines of therapy. As a single agent, elranatamab induced an ORR of 61.0% with a CR or better rate of 37.4% in the phase 2 MagnetisMM-3 trial.
Iberdomide is an oral CELMoD that has demonstrated superior immunomodulatory activity and antiproliferative and proapoptotic activity in myeloma cells compared with traditional immunomodulatory drugs (IMiDs). Preclinical data show that iberdomide promotes T-cell activation and proliferation, leading to stronger T-cell engagement and better T-cell fitness.
"Based on the complementary mechanism of action, it would be rational to think that the combination may improve efficacy—particularly in patients with relapsed/refractory multiple myeloma (搜索)," Suvannasankha explained. "This provided a scientific rationale for the MagentisMM-30 study."
Real-World Evidence Supports Clinical Activity
Complementing the clinical trial data, a separate real-world analysis of 130 patients treated with commercial elranatamab across 9 US centers demonstrated meaningful activity in a heavily pretreated population. The real-world cohort achieved an ORR of 65%, with a VGPR or better rate of 46% and a CR or better rate of 36%.
"Elranatamab retains meaningful activity in a frail, heavily pretreated real-world population," said Andrew J. Portuguese, MD, of Fred Hutch (搜索) and the University of Washington School of Medicine (搜索). "Despite its limitations, elranatamab is an important addition to our therapeutic armamentarium. Our data reinforce its effectiveness beyond the clinical trial population and highlight areas where supportive care may improve outcomes."
The real-world study showed that survival outcomes were comparable for patients who were trial-eligible and trial-ineligible, with hazard ratios of 1.22 for overall survival, 1.36 for progression-free survival, and 0.92 for duration of response.
Study Design and Patient Population
The MagnetisMM-30 trial enrolled patients aged 18 years or older with multiple myeloma (搜索) who had received 2 to 4 lines of therapy, including at least 1 IMiD and at least 1 PI, and were relapsed or refractory to their last line of therapy. All patients were BCMA (搜索)-naive.
The median patient age was 68.0 years, with 40.9% having high-risk cytogenetics, 18.2% having extramedullary disease, and 50% being triple-class refractory. A high proportion (77.3%) had received high-dose chemotherapy and prior stem cell transplantation, and 86.4% were refractory to their prior line of therapy.
Future Directions
The study continues to recruit patients for part 2, which aims to incorporate a larger number of patients and evaluate different doses and schedules of elranatamab and iberdomide to optimize the balance between efficacy and toxicity. The early results support continued evaluation of this promising combination in the treatment of relapsed/refractory multiple myeloma (搜索).