Treatment with daratumumab in patients with relapsed/refractory AL amyloidosis: a multicentric retrospective study and review of the literature.

Management of patients with relapsed or refractory (R/R) AL amyloidosis is complex. Some initial reports have shown positive results with daratumumab in heavily pre-treated AL amyloidosis patients. In this retrospective multicentric study, 38 patients (mean age 64 +/- 9 years) with R/R AL amyloidosis treated with daratumumab were included. Cardiac and renal involvement was present in 76 and 74% of patients, and 42% had >= 3 organs involved. Median number of previous lines of therapy was 2 (range 1-8). Overall hematological response was 72%, including 28% complete responses. The median time to first hematological response was 2 weeks. A high-quality response (>= very good partial response) was obtained in 65% of patients who had never achieved such depth of response previously. Hematological responses were more frequent among patients receiving daratumumab as second-line therapy compared to subsequent therapies (92 vs. 61%). Cardiac and renal organ response rates were 37 and 59%. At 12 months, overall and progression-free survival were 59% (95%CI: 0.36-0.77) and 52% (95%CI: 0.29-0.70), respectively. Daratumumab is a safe and effective drug in the treatment of R/R AL amyloidosis and should be considered early in the course of the disease.