Multiple regimens of no help in cardiac light chain amyloidosis

Treatment with the bortezomib-cyclophosphamide-dexamethasone (CyBorD) combination plus doxycycline falls short of improving progression-free survival (PFS) or cardiac PFS in patients with light chain amyloidosis, according to the results of a trial.

The trial randomized 140 patients (median age 61 years) with Mayo 2004 stage II-III light chain amyloidosis to receive doxycycline 100 mg twice daily along with nine cycles of CyBorD (doxycycline group, n=70) or nine cycles of CyBorD alone (control group, n=70).

The primary outcome was 2-year PFS, defined as the time from randomization to death, haematologic progression (substantial increase in free light chain), or organ progression (heart, kidney, or liver). Cardiac progression was described as an increase in either N-terminal pro B-type natriuretic peptide or cardiac troponin.

There were 34 (48.6 percent) and 33 (47.1 percent) patients in the doxycycline and control groups, respectively, with stage II disease. Progression occurred in 45.7 percent of patients in the doxycycline group and 42.9 percent in the control group, with the difference not achieving statistical significance (hazard ratio [HR], 0.97, 95 percent confidence interval [CI], 0.59–1.60; p=0.91).

Cardiac progression was documented in 41.4 percent of patients in the doxycycline group and 37.1 percent of patients in the control group, while the death rate for both groups by the end of follow-up was the same at 35.7 percent. Neither cardiac PFS (HR, 0.91, 95 percent CI, 0.54–1.55; p=0.74) nor overall survival (HR, 1.04, 95 percent CI, 0.60–1.81; p=0.89) differed significantly between the two groups.