What is belantamab mafodotin-blmf?
Belantamab mafodotin-blmf is a B-cell maturation antigen (BCMA)-directed antibody-drug conjugate. The afucosylated, humanized IgG1, anti-BCMA monoclonal antibody is linked to a microtubule inhibitor conjugate, monomethyl auristatin F (MMAF) by a protease-resistant maleimidocaproyl linker.
How does belantamab mafodotin-blmf work?
Belantamab mafodotin-blmf binds to BCMA on multiple myeloma cells and is internalized by the cell where MMAF is then released by proteolytic cleavage resulting in cell cycle arrest, apoptosis, and tumor cell lysis through antibody-dependent cellular cytotoxicity and phagocytosis.
What is belantamab mafodotin-blmf approved for?
Belantamab mafodotin-blmf is approved for treatment of adult patients with relapsed or refractory multiple myeloma who have received at least four prior therapies, including an anti-CD38 monoclonal antibody, a proteasome inhibitor, and an immunomodulatory agent.
What is the basis for this approval?
Belantamab mafodotin-blmf received an accelerated approval for treatment of relapsed or refractory multiple myeloma based on the DREAMM-2 trial (Lancet Oncol 2020;21(2):207-221). In this randomized, open-label, multicenter, Phase II study, patients received belantamab mafodotin-blmf at a dose of either 2.5 mg/kg or 3.4 mg/kg intravenously once every 3 weeks until disease progression or unacceptable toxicity. The 2.5 mg/kg cohort had an overall response rate of 31 percent (97.5% CI: 20.8-42.6%) in the intention-to-treat population. Belantamab mafodotin-blmf is only available through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) due to the risk of ocular toxicity.
How do you administer this drug for the treatment of multiple myeloma?
Belantamab mafodotin-blmf is administered at a dose of 2.5 mg/kg intravenously once every 3 weeks until disease progression or unacceptable toxicity. Belantamab mafodotin-blmf is given over 30 minutes and is dosed on actual body weight.
Are there any pre-medications needed?
No antiemetics or other pre-medications are recommended with belantamab mafodotin-blmf. Infusion-related reactions (IRR) have been reported with belantamab mafodotin-blmf and patients should be monitored for IRR.
What are the common side effects associated with belantamab mafodotin-blmf (> or =20%)?
The most common adverse events were keratopathy, decreased visual acuity, nausea, blurred vision, pyrexia, infusion-related reactions, thrombocytopenia, and fatigue. Other common side effects included hypokalemia, hyponatremia, increased gamma-glutamyl transferase, hyperglycemia, anemia, neutropenia, increased transaminases, fatigue, increased creatinine phosphokinase, and increased serum creatinine.
What are the uncommon side effects associated with belantamab mafodotin-blmf (less than 10%)?
Uncommon side effects include albuminuria, hypercalcemia, vomiting, sepsis, eye irritation, keratitis, photophobia, renal insufficiency, pneumonia, and antibody development.
Are there any important drug interactions?
Belantamab mafodotin-blmf may enhance the myelosuppressive effect of other myelosuppressive agents. MMAF is a substrate of OATP1B1, OATP1B3, MRP1, MRP2, MRP3, BSEP, and a possible substrate of P-gp.
How do I adjust the dose in the setting of renal or hepatic insufficiency?
Mild to moderate renal impairment and mild hepatic impairment did not have a significant effect on the pharmacokinetics of belantamab mafodotin-blmf and no dose adjustments are needed. Effects in patients with severe renal impairment, requiring dialysis, or with moderate to severe hepatic impairment are unknown.
What should my patients know about belantamab mafodotin-blmf?
* Belantamab mafodotin-blmf has boxed warnings for corneal epithelium changes resulting in vision changes, including vision loss, corneal ulcers, blurred vision, and dry eyes.
* Ophthalmic exams are required at baseline, prior to each dose, and with any visual changes.
* Patients should administer preservative-free lubricant eye drops as recommended during treatment and should avoid wearing contact lenses during treatment unless advised by a health care professional.
What useful links are available regarding belantamab mafodotin-blmf for the treatment of multiple myeloma?
* FDA Approval Announcement: https://bit.ly/3tg86Hw
Any ongoing clinical trials related to belantamab mafodotoin-blmf?
Belantamab mafodotin-blmf is being studied in combination with other multiple myeloma therapies, including lenalidomide, pomalidomide, bortezomib, and dexamethasone. There are also ongoing studies in patients with amyloid light-chain amyloidosis and lymphoma.
CHELSEA MINOR, PHARMD, BCPS, BCOP, is Clinical Pharmacy Specialist of Hematology and Bone Marrow Transplant at Washington University School of Medicine St. Louis. JANELLE E. MANN, PHARMD, BCOP, is Clinical Oncology Pharmacist/ Manager, Clinical Pharmacy Services at Washington University School of Medicine, Saint Louis, Mo. She serves as the Pharmacy Forum column editor. RAMASWAMY GOVINDAN, MD, Professor of Medicine; Anheuser Busch Chair in Medical Oncology; Director, Section of Medical Oncology, Division of Oncology, Washington University School of Medicine, serves as the Pharmacy Forum column physician advisor.
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