Elranatamab for Relapsed/Refractory Multiple Myeloma With Severe Renal Impairment Requiring Hemodialysis

Relapsed/refractory multiple myeloma (RRMM) patients with dialysis-dependent renal impairment face limited therapeutic options due to exclusion from clinical trials, a lack of evidence-based guidelines, and inferior outcomes. Bispecific antibodies targeting B-cell maturation antigen (BCMA) have shown promise in RRMM treatment but remain understudied in this vulnerable population. To illustrate this issue, we introduce the case of a 68-year-old female with triple-class RRMM and end-stage renal disease requiring hemodialysis, treated with elranatamab as a second line treatment following progression after therapy with daratumumab, bortezomib, lenalidomide, and dexamethasone. Despite experiencing grade I cytokine release syndrome during the initial administrations, symptoms were managed effectively with tocilizumab and dexamethasone, allowing treatment continuation. The patient achieved a very good partial remission within 7 weeks. Although hemodialysis dependence persisted, the therapy was well-tolerated with manageable adverse events. According to the literature, BCMA-directed immunotherapies, including teclistamab, belantamab mafodotin, and idecabtagene vicleucel, have shown efficacy in dialysis-dependent RRMM patients, though data remain limited. Pharmacokinetic analyses indicate that mild or moderate renal impairment does not have a significant impact on the pharmacokinetics of elranatamab. Although no retrospective studies or case series have investigated the use of elranatamab in dialysis-dependent patients, a single case report suggests that its administration is both feasible and well-tolerated in this population despite the absence of comprehensive pharmacokinetic data. This review highlights feasibility, safety, and encouraging efficacy of elranatamab in managing RRMM in a dialysis-dependent patient, representing the second case report in the literature. By providing real-world evidence for the use of bispecific antibodies in end stage renal disease patients, this review emphasizes the potential for expanding therapeutic options to this vulnerable population while highlighting the need for vigilant monitoring of infection prevention and management. Prospective studies are warranted to validate these findings and optimize therapeutic strategies for patients with RRMM and severe renal impairment.