In clinical trials with Soliris, paroxysmal nocturnal hemoglobinuria (PNH) patients experienced a substantial improvement in PNH-related fatigue independent of changes in their anemia. This improvement was larger than the improvement in fatigue reported in a separate study of anemic cancer patients treated with erythropoietin (EPO).
Data on 164 patients with PNH were derived from two Phase III studies of Soliris as a treatment for PNH: Triumph, a six-month, double-blind, placebo-controlled study, and Shepherd, a 12-month, open-label study. The study results show that while intravascular hemolysis reduction (decreased LDH) and anemia improvement (increased hemoglobin) were both significantly associated with fatigue improvement (odds ratio 1.11, P<0.001 and 1.29, P=0.005,respectively) hemolysis reduction was predictive of an improvement in fatigue independent of an improvement in anemia in patients with PNH (1.07, P=0.028). The improvement in fatigue was greater (P=0.002) in Soliris-treated PNH patients compared to EPO-treated anemic cancer patients. These data suggest that fatigue experienced by patients with PNH is related directly to hemolysis - the red blood cell destruction that defines the disease - and can be improved independent of correction of anemia. Leonard Bell, CEO of Alexion, said: "This study indicates that patients can experience life-changing improvements in fatigue with long-term Soliris therapy regardless of changes in their anemia."