Blood Cancer Therapy Granted Accelerated FDA Approval

The US Food and Drug Administration (FDA) has given the green light to Elrexfio™ (elranatamab-bcmm), granting it accelerated approval to treat adults with multiple myeloma – a type of blood cancer – who have received at least four previous rounds of certain therapies.

Unlocking new treatment options for myeloma

Multiple myeloma is an aggressive and incurable form of blood cancer that develops in a type of white blood cell called plasma cells, which are found in the bone marrow and develop from B cells. Healthy plasma cells are responsible for producing antibodies to fight infection and disease.

Multiple myeloma is the second most common type of blood cancer, with over 176,000 new cases diagnosed globally each year. For most patients, relapse is almost inevitable after therapy, and approximately half do not survive beyond five years. Many patients go on to receive at least four lines of treatment, with the goal of therapy being to manage the disease while improving quality of life and limiting side effects.

Elrexfio is an antibody-based therapy that is injected under the skin. It is a bispecific antibody, meaning it takes aim at two targets at once; in this case, both B cell maturation antigen (BCMA) – found on myeloma cells – and cluster of differentiation 3 (CD3) – a protein found on T cells. This way, the antibody brings the two cell types together, enabling T cells to kill myeloma cells more easily.

“Accessibility is key to unlocking the potential impact of new treatment options. Unfortunately, novel therapies for triple-class–exposed multiple myeloma can be out of reach for medically underserved populations,” said Jenny Ahlstrom, founder and chief executive officer of the HealthTree Foundation for Multiple Myeloma. “With the approval of Elrexfio, patients have a new off-the-shelf treatment option that can be delivered on an ongoing basis in community clinics, where the majority of patients with multiple myeloma receive their care.”

Accelerated approval of Elrexfio

The FDA’s accelerated approval of Elrexfio was based on data from the Phase 2 MagnetisMM-3 clinical trial, which is yet to be published. The trial evaluated the efficacy of Elrexfio in patients with multiple myeloma who have either relapsed or no longer respond to treatment.

An announcement by the drug’s manufacturer, Pfizer, indicated that a cohort of 97 heavily pre-treated patients (who had received four or more previous lines of therapy, but not BCMA-directed therapy) had an overall response rate of 58%, and an estimated 82% of patients responded to the treatment for at least 9 months.

Longer-term efficacy data, which was presented at the 2023 European Hematology Association meeting and has not been peer-reviewed, suggests that the objective response rate was 61% after approximately 12 months of treatment.

“Most multiple myeloma patients will experience relapse or resistance of their disease to treatment, often facing increased symptom burden and lowering their chance of surviving longer with each attempted line of therapy,” said Professor Ajay Nooka, MagnetisMM clinical trial investigator and director of the Multiple Myeloma Program at Winship Cancer Institute of Emory University. “By offering durable clinical response with an established safety profile and the convenience of subcutaneous administration, Elrexfio provides a much-needed new option for heavily pre-treated multiple myeloma patients who are struggling with relapsed myeloma.”

Common side effects of the treatment include fatigue, reactions at the injection site, diarrhea and upper respiratory tract infections. A boxed warning from the FDA will also be included in Elrexfio’s label due to the risks of developing serious conditions such as cytokine release syndrome – a potentially life-threatening inflammatory reaction that can occur with immunotherapy.

Further trials are now under way to confirm that Elrexfio provides clinical benefit for patients in order to continue the FDA’s approval.

“With significant responses in a patient population with highly refractory disease, we believe Elrexfio is poised to potentially become the new standard of care for multiple myeloma, as we plan to build upon this indication with continued development across the expansive MagnetisMM program,” said Angela Hwang, chief commercial officer and president of global biopharmaceuticals business at Pfizer.

This article is a rework of a press release issued by Pfizer. Material has been edited for length and content.

This article is based on research findings that are yet to be peer-reviewed. Results are therefore regarded as preliminary and should be interpreted as such. Find out about the role of the peer review process in research here. For further information, please contact the cited source.