Elranatamab Significantly Improves PFS in R/R Multiple Myeloma Trial

Elranatamab-bcmm (Elrexfio) monotherapy produced a statistically significant progression-free survival (PFS) improvement vs daratumumab (Darzalex) plus pomalidomide (Pomalyst) and dexamethasone (DPd) among patients with previously treated relapsed/refractory multiple myeloma, according to a press release on topline findings from the phase 3 MagnetisMM-5 trial (NCT05020236).¹

The statistically significant improvement in PFS with elranatamab per blinded independent central review (BICR) reached the trial’s primary end point. The PFS outcomes observed with elranatamab monotherapy exceeded the trial’s pre-specified interim target analysis HR for efficacy, as most patients remained progression-free at the time of analysis. The trial is ongoing for the evaluation of the key secondary end point of overall survival (OS), which was immature at the time of analysis.

The safety and tolerability of elranatamab in the MagnetisMM-5 trial were comparable with prior reports of the agent. Investigators plan to discuss these findings with global health authorities and submit detailed results for presentation at a medical conference in the future.

“Effective intervention earlier in the course of disease represents a critical opportunity to improve outcomes for people living with multiple myeloma. [Elranatamab] has already helped address a significant unmet need in heavily pretreated patients, delivering deep, durable, and clinically meaningful responses,” Jeff Logos, chief oncology officer at Pfizer, stated in the press release.¹ “The MagnetisMM-5 results reinforce our confidence in [elranatamab’s] potential to benefit patients earlier in their treatment journey and support our comprehensive strategy to evaluate [elranatamab] both as monotherapy and as part of combination approaches across multiple lines of therapy.”

Investigators of the open-label, multicenter phase 3 MagnetisMM-5 study are assessing the safety and efficacy of elranatamab compared with standard-of-care DPd among 497 patients with relapsed/refractory multiple myeloma who have received at least 1 prior line of therapy, including lenalidomide (Revlimid) and a proteasome inhibitor. In the experimental arm, patients received elranatamab via subcutaneous administration as 2 step-up priming doses followed by 76 mg each week. Investigators adjusted the dosing frequency to every 2 weeks after 24 weeks if a partial response was sustained for more than 2 months and then to every 4 weeks for all patients after 48 weeks of therapy.

The trial’s primary end points included the incidence of dose-limiting toxicities in part 1, PFS per International Myeloma Working Group (IMWG) criteria in part 2, and the frequency of treatment-emergent adverse effects in part 3.² Secondary end points included OS, objective response rate, duration of response, time to response, complete response rate, minimal residual disease negativity, PFS on the next line of therapy, pharmacokinetics, and health-related quality of life.

Patients 18 years and older with a prior diagnosis of multiple myeloma per IMWG guidelines, measurable disease, prior anti-myeloma therapy including treatment with lenalidomide, and an ECOG performances status of 0 to 2 were eligible for enrollment on the trial. The resolution of any acute effects of any prior therapy to baseline severity or no higher than grade 1 per CTCAE criteria was another requirement for study entry.

Those with smoldering multiple myeloma, plasma cell leukemia, amyloidosis, or POEMS Syndrome were ineligible for enrollment on the trial. Patients were also unable to enroll if they had a stem cell transplant within 12 weeks prior to enrolling, prior treatment with BCMA-directed agents, a live attenuated vaccine within 4 weeks of beginning study treatment, or an investigational product concurrent with study intervention or within 30 days of beginning study treatment.

References

1. Pfizer’s ELREXFIO significantly improves progression-free survival for double-class exposed patients with relapsed or refractory multiple myeloma. News release. Pfizer. April 29, 2026. Accessed April 29, 2026. https://tinyurl.com/43nmxye6
2. A study to learn about the study medicine elranatamab alone and with daratumumab in people with multiple myeloma who have received other treatments (MAGNETISMM-5). ClinicalTrials.gov. Updated March 27, 2026. Accessed April 29, 2026. https://tinyurl.com/mtvebbuj