Pfizer Announces That Topline Results In The Phase 3 MagnetisMM-32 Trial Of ELREXFIO Demonstrated Clinically Meaningful And Statistically Significant Benefit For Patients Whose Disease Progressed After Anti-CD38 Therapy And Lenalidomide, With Median PFS Not Yet Reached

Pfizer Inc. (NYSE:PFE) today announced topline results from the Phase 3 MagnetisMM-32 study evaluating ELREXFIO® (elranatamab) as monotherapy in adults with relapsed or refractory multiple myeloma (RRMM) who received at least one prior line of treatment with anti-CD38 therapy (daratumumab or isatuximab) and lenalidomide.

At the pre-specified interim analysis for efficacy, the study met its primary endpoint of progression-free survival (PFS) as assessed by blinded independent central review (BICR). ELREXFIO demonstrated a statistically significant and clinically meaningful reduction in the risk of disease progression or death versus investigator’s choice of elotuzumab, pomalidomide and dexamethasone (EloPd); pomalidomide, bortezomib and dexamethasone (PVd); or carfilzomib and dexamethasone (Kd). MagnetisMM-32 used one of the broadest standard-of-care comparators in a Phase 3 BCMA bispecific trial in this setting, with investigator’s choice of three established regimens.

More than 75% of patients receiving ELREXFIO had not experienced disease progression or death from any cause at the time of the analysis1, with an estimated 68% PFS at 18 months. Data for overall survival (OS), a key secondary endpoint, remain immature, and follow-up will continue to the next pre-specified OS analysis.

The safety profile of ELREXFIO in MagnetisMM-32 was consistent with its known profile and no new safety signals were identified. Infection prophylaxis measures instituted from the beginning of the study helped mitigate infection risk, including Grade 3 or higher infections. Grade ≥3 infections were observed in 27.5% of patients receiving ELREXFIO vs. 18.1% of patients on investigator’s choice, and Grade 5 infections were observed in 0.8% of patients receiving ELREXFIO vs 1.6% of patients on investigator’s choice.

Pfizer plans to submit these data to global health authorities, with detailed results to be shared at a future medical meeting and submitted for publication.