The Food and Drug Administration (FDA) granted accelerated approval to the drug belantamab mafodotin-blmf (BLENREP; GlaxoSmithKline) on August 5, 2020, for the treatment of adult patients with relapsed or refractory multiple myeloma. These patients must have previously been treated with at least 4 therapies, including an anti-CD38 monoclonal antibody, a proteasome inhibitor, and an immunomodulatory agent. The results of phase II multicenter DREAMM-2 trial provided substantial evidence of the effectiveness of the treatment.
Patients were given belantamab mafodotin intravenously at a dose of either 2.5 or 3.4 mg/kg once every 3 weeks until the disease progressed or the toxicity became intolerable. In the experiment, the total response rate was 31% in the group that received 2.5 mg/kg, while it was 34% in the cohort that received 3.4 mg/kg. The most common adverse effect was keratopathy, which appeared in 71% and 77% of patients. Alterations in visual acuity, blurred vision, and dry eye were some of the other ocular toxicities that were observed.
Belantamab mafodotin’s prescribing instructions in the United States include a boxed warning for ocular toxicity, and the drug can only be obtained through a restricted program that falls under a Risk Evaluation and Mitigation Strategy. This article provides a summary of the data and the review procedure that the FDA went through to justify the accelerated approval of belantamab mafodotin administered intravenously at a dose of 2.5 mg/kg once every 3 weeks. This approval could be conditional on the confirmation and elaboration of the therapeutic benefit seen in the confirmatory trial (s).