New Approval in Multiple Myeloma Treatment: Belantamab Mafodotin-blmf

On August 5, 2020, the US Food and Drug Administration (FDA), for adults previously given an anti-CD38 monoclonal antibody, a proteasome inhibitor and immunomodulatory drugs in at least 4 treatments, with relapsed or refractory multiple myeloma diagnoses, granted accelerated approval to belantamab mafodotin-blmf.

B-cell maturation antigen (BCMA)-expressing myeloma cells are recognized by belantamab, which binds to their surface. Belantamab mafodotin is then taken up by the myeloma cells. Mafodotin released inside the cell causes cell death to occur.

Belantamab mafodotin-blmf, whose efficacy was evaluated in a multicenter study, was administered by intravenous injection 1 time every 3 weeks until disease progression or unacceptable side effects. In the study group, researchers identified an overall response rate of 31% and reported that, among responders, 73% responded for 6 months or longer to the treatment.

Serious side effects frequently observed during treatment include vision loss and corneal ulceration resulting from changes in the corneal epithelium, blurred vision and dry eyes. In ≥%20 of patients receiving this treatment, excessive fluid accumulation in the cornea (keratopathy), decreased visual acuity, nausea, blurred vision, an excessive rise in body temperature (pyrexia) and fatigue were observed. To prevent these risks, an eye examination must be performed before every dose.

Because of its serious ocular adverse effects, belantamab mafodotin-blmf is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS).

Belantamab mafodotin-blmf was approved based on the treatment response rate obtained with its use. Continued approval for this treatment option may depend on the confirmation and description of clinical benefit in further studies.

The FDA granted belantamab mafodotin-blmf orphan drug designation, breakthrough therapy designation and priority review status. “Orphan Drug Status” is an FDA program supporting drugs developed to treat relatively rare diseases affecting fewer than 200 thousand people annually in the United States.