Early experience with daratumumab-containing regimens in patients with light-chain cardiac amyloidosis.

Abstract

Background: Immunoglobulin light-chain (AL) amyloidosis is a lethal condition resulting from misfolded immunoglobulin ALs produced by clonal CD38-positive plasma cells. Treatment with daratumumab, an anti-human CD38 monoclonal antibody, led to higher frequencies of complete hematologic response and better clinical outcomes compared with conventional treatment. This study sought to evaluate the survival benefit of daratumumab-containing regimens in patients with AL cardiac amyloidosis.

Methods and results: We examined 65 consecutive patients with AL cardiac amyloidosis (mean age: 67.2 ± 10.4 years, male: 69 %) who underwent chemotherapy. We divided patients into a daratumumab group, which used daratumumab-containing regimens before second-line treatment (n = 32), and a conventional treatment group (n = 33). Compared with the conventional treatment group, the daratumumab group tended to be older, but there were no significant differences between groups in biomarkers and echocardiographic parameters. A total of 26 patients (40 %) died (median follow-up duration: 395 days). Kaplan-Meier survival analysis showed that the daratumumab group had significantly lower mortality compared with the conventional treatment group (p = 0.04; log-rank test). Cox hazard analysis revealed that use of daratumumab-containing regimens was associated with lower mortality after adjustment for the revised Mayo staging of AL amyloidosis (hazard ratio: 0.32; 95 % confidence interval: 0.12 to 0.85; p = 0.02).

Conclusion: Daratumumab-containing regimens may be associated with improved survival in patients with AL cardiac amyloidosis.