FDA Grants Elranatamab With Breakthrough Therapy Designation for Relapsed or Refractory Multiple Myeloma

The FDA has granted elranatamab (Pfizer) with Breakthrough Therapy Designation for the treatment of patients with relapsed or refractory multiple myeloma (RRMM).

The novel drug is a B-cell maturation antigen (BCMA)-CD3-targeted bispecific antibody (BsAb). Elranatamab was developed to attach to BCMA, which is highly expressed on the surface of MM. The CD3 receptor found on the surface of T-cells connects and activates them to kill myeloma cells. The binding affinity of elranatamab for BCMA and CD3 has been engineered to elicit potent T-cell mediated anti-myeloma activity.

“The FDA’s Breakthrough Designation recognizes the potential of elranatamab as an innovative medicine for people with multiple myeloma whose disease has relapsed or is refractory to existing treatments, which at present leaves very few avenues for staving off this currently incurable cancer,” said Chris Boshoff, MD, PhD, chief development officer, Oncology and Rare Disease, Pfizer Global Product Development, in a press release. “This marks Pfizer’s twelfth FDA Breakthrough Therapy Designation in Oncology, a testament to our relentless commitment to developing transformational cancer medicines in areas of high unmet need. We look forward to working with the FDA to accelerate the development of this therapy.”

BsAbs are defined as a novel form of cancer immunotherapy that bind to and engage 2 different targets at once, and as one arm binds directly to specific antigens on cancer cells, the other arm binds to T-cells and brings both cell types together. The bsAb is delivered subcutaneously, which is more convenient than intravenous administration and may mitigate the risk of potential adverse events, such as cytokine release syndrome (CRS).

The Breakthrough Therapy Designation was based on findings from a 6-month follow-up of cohort A of MagnetisMM-3, a multicenter, phase 2 trial analyzing the safety and efficacy of elranatamab monotherapy in patients with RRMM. Patients received subcutaneous (SC) elranatamab 76 mg weekly with a 2-step-up priming dose regimen administered during the first week.

The study found that elranatamab had a manageable safety profile. The most common treatment-emergent adverse event regardless of causality was CRS, with most cases being either grade 1 or grade 2.

MagnetisMM-3 is a part of the MagnetisMM clinical research program, which has registration-intent trials planned or ongoing analyzing elranatamab both as monotherapy and in combination with standard or novel therapies, spanning multiple patient populations from newly diagnosed MM, double-class exposed disease, and RRMM.

Elranatamab has also been granted Orphan Drug Designation by the FDA and the European Medicines Agency for the treatment of MM.

REFERENCE

Pfizer’s Elranatamab Granted FDA Breakthrough Therapy Designation for Relapsed or Refractory Multiple Myeloma. Pfizer. November 3, 2022. Accessed November 4, 2022. https://www.pfizer.com/news/press-release/press-release-detail/pfizers-elranatamab-granted-fda-breakthrough-therapy