Belantamab in Combination with Dexamethasone in Patients with Triple-class Relapsed/Refractory Multiple Myeloma

Triple-class relapsed/refractory multiple myeloma (RRMM) has a poor prognosis. This study analyzed the clinical outcomes of Belantamab mafadotin in combination with dexamethasone (Bd) in triple-class RRMM.

We identified 35 patients with triple-class RRMM who received Bd at the University of Kansas from October 2019 to November 2021.

The median age was 66 years (42-85) and the median prior lines of therapy was 5 (3-15). Nineteen (54%) patients had R-ISS stage III disease, 15 (43%) patients had high-risk cytogenetics, and 15 patients (43%) had extramedullary disease (EMD). Eight patients received prior BCMA-targeted therapy. Overall response rate (ORR) was 43%, with 23% achieving very good partial response and better. At a median follow up of 10.7 months, the median progression-free survival and survival were 4.9 and 10.7 months, respectively. The most common adverse event was keratopathy, which occurred in 30 (86%) patients. Twenty-four patients required dose reduction or delay due to keratopathy. Other common toxicities included anemia (83%), thrombocytopenia (80%), neutropenia (34%), and elevated liver function tests (51%).

Our analysis shows Bd has good activity in triple-class RRMM. Keratopathy remains a challenging AE and the leading cause of dose reduction, delay and treatment cessation.