Immunoglobulins in Multiple Myeloma Patients Receiving a BCMA-Directed T Cell Engager

Overview

Bispecific antibody therapies targeting BCMA (B-cell maturation antigen) represent a novel therapeutic approach for patients with multiple myeloma. They are currently used in cases of refractory multiple myeloma but are also being investigated in earlier lines of treatment. However, these new therapies can lead to deeper immunosuppression and exacerbate an underlying immunosuppressive state in patients with multiple myeloma. As a result, infectious complications are common with these therapies and are a significant concern. Therefore, preventing infections in this population is crucial. However, data on the best strategies for prevention are currently lacking.

Although the effectiveness of immunoglobulins (Ig) has been demonstrated, it remains to be determined whether immunoglobulin administration is necessary for all patients receiving these therapies or only for those with low serum immunoglobulin G (IgG) levels. Furthermore, the optimal target IgG level to achieve in order to reduce the risk of infections is also unknown in this specific population of multiple myeloma patients. Guidance needs to be provided to the clinicians to better support MM patients undergoing this novel therapy by addressing the hypogammaglobulinemia and therefore limiting and ideally avoiding the high risk of infections. In this prospective, randomized, unblinded, multicenter study, as per the standard of care approach, every patient with relapsed refractory MM receiving a BCMA-directed TCE with history of recurrent or severe infections and/or total IgG level less than 4 g/L will receive Ig support (intravenous ou subcutaneous). Once on Ig supplementation, the optimal target trough IgG level to achieve is not well established. The goal of this study is therefore to better define, in this patient population , the target trough IgG level to achieve a reduction in the incidence of severe infections. The primary objective is to demonstrate the non-inferiority in the cumulative incidence of severe infections at 3 months between patients on Ig support with a target trough IgG level of 4-6 g/L (experimental group) versus a target trough IgG level of 8-10 g/L (standard of care (SOC) group).