Oncology Drug Reference Sheet: Elranatamab-Bcmm

March 26, 2024 by Chelsea Backler MSN, APRN, AGCNS-BC, AOCNS®, VA-BC

This ONS resource was produced for educational purposes only. Refer to the full elranatamab-bcmm (Elrexfio™) package insert (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=f6fea598-ff58-4a20-b5e8-8a51f37d8beb) for all details.

DRUG INFORMATION
Classification	Immunotherapy; bispecific T-cell engager/bispecific antibody
Mechanism of Action	Binds to BCMA on plasma cells, plasmablasts, and multiple myeloma cells and to CD3 on T cells, causing cytokine release and leading to lysis of multiple myeloma cells
Indication	Adults with relapsed or refractory multiple myeloma who received at least four prior lines of therapy, including a proteasome inhibitor, immunomodulatory agent, and anti-CD38 monoclonal antibody
ADMINISTRATION
Dosing, Frequency, and Duration	Day	Dose
	1	Step-up dose 1: 12 mg
	4	Step-up dose 2: 32 mg
	8	First treatment dose: 76 mg
	One week after first treatment dose and weekly thereafter through week 24	Subsequent treatment doses: 76 mg
	Week 25 and every two weeks thereafter
Route	Subcutaneous injection
Safe Handling	Elranatamab-bcmm is a potentially hazardous drug per the National Institute for Occupational Safety and Health definition (https://www.usp.org/compounding/general-chapter-hazardous-drugs-handling-healthcare#:~:text=The%20National%20Institute%20for%20Occupational,low%20doses%2C%20genotoxicity%2C%20or%20structure) because of its embryo-fetal toxicity. Follow safe-handling precautions (https://www.ons.org/books/chemotherapy-and-immunotherapy-guidelines-and-recommendations-practice-second-edition).
ADVERSE REACTIONS
Decreased lymphocytes, neutrophils, hemoglobin, white blood cells, and platelets Upper respiratory tract infection, pneumonia, and cough Diarrhea, decreased appetite, and nausea Fatigue, musculoskeletal pain, and pyrexia Rash Injection site reaction Cytokine release syndrome (CRS)
WARNINGS
Black box warnings: CRS and neurologic toxicity, including immune effector cell–associated neurotoxicity syndrome (ICANS)
Other warnings: infections, neutropenia, hepatotoxicity, and embryo-fetal toxicity
NURSING CONSIDERATIONS
Pretreatment	Verify patients’ pregnancy status and monitor complete blood cell counts, liver enzymes, and bilirubin at baseline and regularly throughout treatment. Administer premedications (acetaminophen 650 mg orally, dexamethasone 20 mg orally or via IV, and diphenhydramine 25 mg orally) one hour prior to each dose in the step-up schedule, including the first treatment dose. Elranatamab-bcmm is available only through a REMS program (https://tec-talrems.com/#Main); provide patients with a wallet card (https://www.elrexfiorems.com/#Main/Prescribers) at the start of treatment.
Administration	The abdomen is the preferred injection site.
Post-treatment	In the drug’s clinical trial, CRS occurred (https://classic.clinicaltrials.gov/ct2/show/NCT04649359) in 58% of patients; median time to onset was two days but developed up to nine days after dose administration. In the clinical trial, neurologic toxicity occurred (https://classic.clinicaltrials.gov/ct2/show/NCT04649359) in 59% of patients (ICANS in 3.3%); median time to onset of ICANS was three days after dose administration. Patients require hospitalization for 48 hours after the first step-up dose and 24 hours after second step-up dose. CRS and ICANS can occur concurrently, subsequently, or in the absence of each other.
PATIENT EDUCATION
Report fever or signs of infection, neurologic symptoms (e.g., dizziness, confusion, changes in consciousness), shortness of breath, jaundice, dark urine, and abdominal pain. Delayed onset of CRS or ICANS is possible; seek immediate evaluation if you develop symptoms. Avoid pregnancy or breastfeeding during treatment and for four months after your last dose. Carry a wallet card at all times and present it to all healthcare providers.
RESOURCES
Patient Resources	U.S. Food and Drug Administration medication guide (https://www.accessdata.fda.gov/drugsatfda_docs/label/2023/761345s000lbl.pdf#page=22) Branded product patient-facing website (https://patient.aphexda.com/)
Healthcare Professional Resources	Package insert (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=f6fea598-ff58-4a20-b5e8-8a51f37d8beb) Patient assistance (https://www.pfizerpro.com/patient-assistance) Product website (https://elrexfio.pfizerpro.com/) CRS Huddle Card (https://www.ons.org/huddle-cards/cytokine-release-syndrome-crs-huddle-cardtm) ICANS Huddle Card (https://www.ons.org/huddle-cards/immune-effector-cell-associated-neurotoxicity-syndrome-huddle-card)
Other Resources	National Cancer Institute drug information (https://www.cancer.gov/about-cancer/treatment/drugs/elranatamab-bcmm) REMS (https://www.accessdata.fda.gov/scripts/cder/rems/index.cfm?event=IndvRemsDetails.page&REMS=421)

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