Daratumumab Is Safe and Effective for Relapsed/Refractory AL Amyloidosis

A new study from an Israeli research team observed favorable safety, tolerability, and efficacy of daratumumab for the treatment of non-selective relapsed or refractory light-chain (AL) amyloidosis.

AL amyloidosis is marked by the production of abnormal antibodies called light chains. Patients with relapsed/refractory AL amyloidosis (RRAL) are likely to have poor prognosis. Emerging data shows promising results for daratumumab for treatment of AL amyloidosis. This study sought to assess the efficacy of the drug as a monotherapy and in combinations for treating RRAL.

The retrospective, multisite study assessed clinical outcomes for 49 patients who were diagnosed with RRAL between 2008 and 2018, 27% of whom also had multiple myeloma (MM). Patients were either treated with daratumumab alone or in combination.

The overall response rate to treatment as 81%, with 64% of patients achieving a very-good partial response or better. Concurrent MM was associated with lower response rates (odds ratio, 0.19; 95% confidence interval, 0.04‐0.81; P=0.03). Median progression‐free survival (PFS) was 28.4 months, and median overall survival (OS) was not reached. PFS and OS at two years were 68.6±7.5% and 90.4±4.6%, respectively. Hematologic response was found to correlate with prolonged PFS and OS.

Daratumumab was well tolerated, with no patients discontinuing treatment due to toxicity.

“Our data supports favorable safety tolerability and efficacy of daratumumab among non-selective RRAL patients in a real‐world setting,” the researchers concluded.

Findings from this study were published in the European Journal of Haemetology.