Retrospective case-control study of iron deficiency among daratumumab-treated newly diagnosed multiple myeloma patients

Iron deficiency (ID) is often overlooked in patients with hematological malignancies due to other potential etiologies. Daratumumab is commonly used for treating multiple myeloma (MM). Although anemia is a common hematological toxicity associated with daratumumab, the contribution of ID in MM patients has not been systematically investigated. A retrospective case-control study at the Mayo Clinic (Rochester, MN) evaluated ther prevalence of ID in newly diagnosed (ND)MM patients. Cases were patients receiving daratumumab, ixazomib, lenalidomide, and dexamethasone (Dara-IRD; n=55), controls were age- and sex-matched NDMM patients receiving bortezomib, lenalidomide, and dexamethasone (VRD; n=20) as induction therapy. At 1 year, nearly 50% of Dara-IRD treated patients met the criteria for ID (ferritin < 30 μg/L) compared with none of the VRD-treated controls. All Dara-IRD treated patients had a decrease in ferritin at 1 year from baseline compared with only 45% of VRD-treated patients. The authors conclude that these findings identify a marked clinical signal of ID among NDMM patients receiving daratuumab-based treatment.