Safety and tolerability of lenalidomide maintenance dosing in patients with multiple myeloma post-autologous stem cell transplant

For transplant-eligible newly diagnosed multiple myeloma patients, autologous hematopoietic stem cell transplant followed by maintenance lenalidomide is a standard of care practice. Maintenance lenalidomide dosing practices vary amongst physicians and current literature lacks comparisons on intermittent versus continuous dosing. In this retrospective study, we compared the safety, tolerability, and efficacy of continuous versus intermittent lenalidomide dosing.This single-center, retrospective review included 72 patients with multiple myeloma receiving lenalidomide maintenance between 2018 and 2021. The primary objective was to determine the incidence of dose modification, defined as any dosage reduction, delay in treatment, or discontinuation of therapy. The secondary objectives were to determine the incidence of hematological and non-hematological toxicities between the two groups.A total of 58 patients in the continuous group and 14 patients in the intermittent group were included. Fifty-four percent of patients in the continuous group required dose modification versus 30% in the intermittent group. Patients who received continuous dosing appeared to have a higher incidence of adverse events when compared to intermittent dosing with the most common adverse events being neutropenia, fatigue, and rash. Twenty-four patients in the continuous group switched to an intermittent schedule after an adverse event. Of these patients, only 8% required further dose modification.The higher incidence of lenalidomide dose modifications in the continuous arm suggests that a majority of patients are not able to tolerate continuous lenalidomide maintenance. A more tolerable option for maintenance may be an intermittent schedule, as reflected by the favorable safety outcomes in this group.