Primary systemic amyloidosis: comparison of melphalan and prednisone versus placebo.

Satisfactory treatment for primary amyloidosis does not exist. Because the amyloid fibrils consist of a portion of a monoclonal light chain, it appears reasonable to treat amyloidosis with alkylating agents that are effective against the plasma cells that synthesize monoclonal light chains. Fifty-five patients with primary systemic amyloidosis were randomized (double blind) to melphalan-prednisone or placebo. In comparison with the placebo group, patients given melphalan-prednisone were able to continue on treatment for a longer time and to receive larger doses before the code was broken. Among this group, the nephrotic syndrome disappeared in two patients and urinary excretion of protein was reduced by more than 50% in eight others. Of 13 patients who received melphalan-prednisone for more than 12 mo, 6 improved, 3 were stable, and 4 had progression of disease. Survival did not differ significantly between the groups.