Safety of Subcutaneous Daratumumab in Anti-CD38 Monoclonal Antibody-Naïve Patients with Plasma Cell Disorders: A Multicenter Real-Life Experience.

BACKGROUND: Daratumumab, an anti-CD38 monoclonal antibody, is used for treatment of multiple myeloma (MM) and light chain amyloidosis at an intravenous dosage of 16 mg/kg or at a subcutaneous fixed dose of 1800 mg. However, the subcutaneous formulation has only recently been approved in Europe, and real-life data on its safety are still few. OBJECTIVE: In this multicenter retrospective real-life experience, we provided evidence for the safety of subcutaneous daratumumab in plasma cell disorders. PATIENTS AND METHODS: A total of 189 patients diagnosed with MM or light chain amyloidosis were included in this retrospective study, and all subjects were daratumumab-naïve. Primary endpoint was safety of subcutaneous daratumumab, especially for infusion-related reaction (IRR) incidence and severity. All patients received premedication with dexamethasone, paracetamol, and antihistamine, with montelukast usage in 85% of cases. RESULTS: Eight patients (4%) experienced IRRs, mainly of grade I-II, and other frequent toxicities were: hematological (thrombocytopenia, 4%; neutropenia, 5%; lymphopenia, 6%) and non-hematological (pneumonia, 4%; diarrhea, 2%; and cytomegalovirus reactivation, 0.5%). In our multicenter retrospective real-life experience, subcutaneous daratumumab was well-tolerated with an excellent safety profile with a very low (4%) IRR incidence, even in frailer MM patients with severe renal impairment or increased body weight. CONCLUSIONS: Subcutaneous daratumumab was safe in a real-life setting including patients with severe renal failure and advanced disease. However, further studies on larger and prospective cohorts are required to confirm our real-life observations.

Serum Free Light-Chain Ratio at Diagnosis Is Associated with Early Renal Damage in Multiple Myeloma: A Case Series Real-World Study.

The serum free light-chain (FLC) ratio is a sensitive tool for the differential diagnosis of plasma cell disorders and is biomarker of multiple myeloma (MM) progression from premalignant conditions. Here, we investigate the potential role of FLC ratio at diagnosis in identifying early renal damage in MM patients and other correlations with clinical, laboratory, and molecular findings. A total of 34 MM patients who had undergone autologous stem cell transplantation were included in this retrospective case series study, and FLC quantification was performed with nephelometric assays. In our study, sFLC ratio was significantly associated with light-chain MM and ß-2 microglobulin levels, likely indicating a high disease burden at diagnosis, especially in patients without heavy chain M-protein at serum electrophoresis. Moreover, the sFLC ratio was inversely correlated with glomerular filtration rate, possibly identifying early renal damage in MM patients. Our preliminary results confirm the importance of early sFLC evaluation, especially in patients with the light-chain MM type and low disease burden, to minimize the risk of late renal failure.

Efficacy and safety of belantamab-mafodotin in triple-refractory multiple myeloma patients: A multicentric real-life experience.

Belantamab-mafodotin is an innovative and selective treatment for multi-refractory/relapsed multiple myeloma (MM) patients; however, available real-life experiences on efficacy and safety are limited. In this real-world multicentric retrospective study, we enrolled 28 MM patients treated in four Hematology units of Campania region, Italy, who received a median of six treatment lines prior to belantamab-mafodotin. The overall response rate (ORR) was 40% (complete remission, CR, 11%; very good partial remission, VGPR, 11%; and partial remission, PR, 18%), with a median progression-free survival (PFS) and overall survival (OS) of 3 and 8 months, respectively. One of the most frequent drug-related adverse events was keratopathy observed in nine (32%) patients, leading to therapy discontinuation in only three (11%) of them. Moreover, 22 out of 28 total patients who were treated with at least two administrations achieved an ORR of 50% (CR, 14%; VGPR, 14%; and PR, 22%) with a median PFS and OS of 5 and 11 months, respectively. In conclusion, our multicentric study confirmed efficacy and safety of belantamab-mafodotin in triple-refractory MM patients even in the real-life setting.