How is systemic AL amyloidosis treated?
The control of light-chain production by proliferating plasma cells has been the rationale for the use of cytotoxic agents. Melphalan- and dexamethasone-containing regimens have been shown to be effective. In low-risk patients with no cardiac involvement, high-dose chemotherapy with autologous peripheral blood stem cell transplantation can result in improvement of the patient’s clinical condition, but treatment-related toxicity can be high. In intermediate- and high-risk patients, high- or attenuated-dose chemotherapy without stem cell transplant is recommended. Bortezomib- and lenalidomide-containing regimens are being investigated and show great promise. Dartumumab (anti-CD38) can also be added to these regimens to eliminate clonal B cells. Any of these therapies need to decrease the serum/urine levels of free light chains by over 50% to increase survival. Digitalis, calcium channel blocker, and β blockers should be avoided in patients with cardiac involvement due to the consequent adverse cardiac events. A therapy being investigated for all types of amyloidosis is the combination of miridesap, which binds SAP and causes it to be cleared from the blood, and dezamizumab, which is an antibody against SAP which fixes complement and stimulates macrophages to ingest amyloid deposits in tissue.
