Treatment with the Terminal Complement Inhibitor Eculizumab Improves Anemia in Patients with Paroxysmal Nocturnal Hemoglobinuria: Phase III Triumph Study Results.

Paroxysmal nocturnal hemoglobinuria (PNH) is a potentially life-threatening acquired hemolytic anemia in which red blood cells (RBCs) lacking complement inhibitory proteins are sensitive to complement-mediated destruction or hemolysis. Intravascular hemolysis in these patients often results in the need for clinical support with packed RBCs (PRBCs) in order to maintain tolerable hemoglobin levels. Eculizumab, a terminal complement inhibitor, has recently been shown in a placebo-controlled randomized phase III clinical trial (TRIUMPH) to reduce intravascular hemolysis and transfusion requirements in patients with PNH. Reported here is a detailed analysis of the effect of eculizumab on various parameters of anemia in these study patients. Eculizumab-treated patients, as compared to placebo, showed an 85.8% decrease in intravascular hemolysis (as measured by LDH area under the curve, p 12 cells/L at baseline to 2.05x10 12 cells/L at 26 weeks (p 12 cells/L to 1.16x10 12 cells/L). The increase in PNH RBC mass was associated with an increase in hemoglobin levels in eculizumab-treated patients relative to placebo (p 25 units/year, p