Elranatamab Improves Progression-Free Survival in Multiple Myeloma Phase 3 Trial

Pfizer reported positive topline results from the phase 3 MagnetisMM-5 trial evaluating elranatamab (ELREXFIO) in adults with relapsed or refractory multiple myeloma, demonstrating improved progression-free survival vs standard therapy, with important implications for oncology nursing care and monitoring.

What do the progression-free survival results mean for oncology nursing care?

MagnetisMM-5 met its primary end point, showing a statistically significant and clinically meaningful improvement in progression-free survival with elranatamab compared with daratumumab, pomalidomide and dexamethasone. The primary end point was assessed by blinded independent central review.

The progression-free survival benefit exceeded the prespecified interim hazard ratio target, with most patients receiving elranatamab remaining progression-free at the time of analysis.

For oncology nurses, these findings suggest a potential shift toward earlier use of bispecific antibodies in the treatment continuum. As patients may remain on therapy longer without progression, sustained monitoring, adherence support and patient education will be increasingly important in clinical practice.

Overall survival remains immature and continues to be evaluated as a key secondary end point.

How is elranatamab administered and what should nurses monitor?

MagnetisMM-5 is an open-label, multicenter, randomized phase 3 study comparing elranatamab monotherapy with standard-of-care daratumumab plus pomalidomide and dexamethasone in patients with relapsed or refractory multiple myeloma.

The trial enrolled 497 patients across 26 countries who had received at least 1 prior line of therapy, including lenalidomide and a proteasome inhibitor.

Elranatamab is administered subcutaneously using a step-up dosing strategy, beginning with 2 priming doses followed by weekly 76 mg dosing. For patients achieving sustained response, dosing intervals may be extended to every 2 weeks after 24 weeks and every 4 weeks after 48 weeks.

From a nursing perspective, step-up dosing requires coordination of care, including inpatient monitoring following initial doses and patient education regarding the rationale for dose escalation. Nurses play a central role in reinforcing adherence to dosing schedules and recognizing early signs of toxicity.

What safety risks should oncology nurses be prepared to manage?

The safety profile of elranatamab in MagnetisMM-5 was consistent with prior studies, with no new safety signals identified.

Cytokine release syndrome (CRS) remains a key toxicity and is common with treatment. Symptoms may include fever ≥100.4°F (38°C), hypotension, dyspnea, tachycardia and neurologic changes.

Neurologic toxicities, including confusion, decreased level of consciousness, cognitive changes and motor impairment, were also reported.

Patients require hospitalization for monitoring following initial step-up doses, underscoring the importance of inpatient oncology nursing teams in early toxicity identification and management. Nurses should be prepared to assess neurologic status frequently and escalate care as needed.

Infection risk is notable, with upper respiratory infections and pneumonia reported. Elranatamab is also associated with cytopenias, including decreased white blood cell counts, and laboratory abnormalities such as elevated liver enzymes.

Common adverse effects include fatigue, injection site reactions, diarrhea, musculoskeletal pain, decreased appetite, rash, cough, nausea and fever.

Oncology nurses play a critical role in patient education, including counseling on early symptom reporting, infection prevention strategies and adherence to monitoring requirements. Ongoing assessment and coordination with the multidisciplinary team are essential to optimize patient outcomes and manage treatment-related toxicities.

References

1. Pfizer Inc. Pfizer’s ELREXFIO significantly improves progression-free survival for double-class exposed patients with relapsed or refractory multiple myeloma. Press release. April 29, 2026.