Abstract: Abstract 3480 Background: Paroxysmal nocturnal hemoglobinuria (PNH) is a chronic and life-threatening hematopoietic stem cell disorder characterized by uncontrolled complement-mediated hemolysis. PNH, in large part due to chronic hemolysis and platelet hyperactivation, is associated with thromboembolism (TE), one of the leading causes of disease mortality. Eculizumab, a monoclonal antibody that inhibits terminal complement activation, has been shown in clinical trials to reduce hemolysis and the incidence of TE. The International PNH Registry provides the opportunity to understand from real world experience the impact of eculizumab on TE reduction in PNH patients. Aim: To assess the risk factors for TE and mortality in PNH patients enrolled in the Registry and to assess the effectiveness of eculizumab in reducing PNH-associated TEs. Methods: Patients are eligible for the Registry if they have a detectable PNH clone, regardless of disease severity, comorbidities, or treatments (past, current or planned). As of June 30, 2012, there were 1547 patients enrolled from 25 countries on 5 continents. Patients were excluded from analysis if they were missing key demographic variables or dates of eculizumab use, or did not yet have follow-up information. The cumulative incidence of TE was determined using competing risks methods to take into account bone marrow transplantation and death, while Kaplan-Meier methods were used for the cumulative incidence of mortality. Risk factors for TE and mortality were explored using a Cox proportional hazards model with stepwise selection (the significance level was relaxed to P=0.20 due to the small number of events for analysis). Variables examined in the models included: ethnicity; prior TEs, bone marrow disorders, impaired renal function, impaired hepatic function (IHF), abdominal pain, dysphagia, dyspnea, easy bruising/bleeding, fatigue, headache, hemoglobinuria, Karnofsky performance score, granulocyte clone size and lactate dehydrogenase (LDH) at enrollment, red blood cell (RBC) transfusions 6 months prior to enrollment as a marker for hemolysis, and treatments after enrollment (eculizumab and warfarin/heparin). Results: The mean age of the 1047 patients eligible for analysis was 45 years; 537 patients (51.3%) were female and 868 were Caucasian (82.9%). Anti-coagulants (heparin/warfarin) were used by 28% of patients and eculizumab was used by 51% during follow-up (18% used both). During a mean (SD) follow-up of 22.5 (18.4) months, 16 patients had a TE and 51 were deceased. Patients taking eculizumab during follow-up had a cumulative incidence of TE at 1 year of 0.41% and 1.35% at 2 years, while patients not taking eculizumab had TE incidence of 1.70% and 2.61% at 1 and 2 years, respectively. In the multivariate Cox model, the greatest associations with TE were RBC transfusions in the 6 months before enrollment (hazard ratio [HR]=9.61), history of IHF (HR=4.78), dyspnea (HR=2.42) and headache (HR=2.33) at enrollment. While controlling for these variables, eculizumab had a significant protective effect (HR=0.23, 95% CI = 0.08–0.66). The cumulative incidence of mortality in eculizumab-treated patients was 2.31% and 4.21% at 1 and 2 years, while in untreated patients it was 4.40% and 7.01%, respectively. In the multivariate model of mortality, the greatest associations were age 60+ years (HR=4.72), Karnofsky score 〈 80 (HR=2.34), fatigue at enrollment (HR=1.94), and recent RBC transfusion (HR=1.75). While controlling for these variable, eculizumab had a significant protective effect (HR=0.41, 95% CI = 0.23–0.73). Conclusions: This analysis of a large international cohort of ‘real world’ patients with PNH showed that eculizumab is associated with a significantly reduced risk of TE and mortality, consistent with prior research. Recent RBC transfusion, a surrogate marker for hemolysis, was associated with increased risk of TE and mortality. Several symptoms and hepatic dysfunction also showed increased risks for these outcomes. As might be expected, older age and low performance status were associated with mortality. These data should be interpreted within the context of a contemporary cohort of PNH patients who may or may not be treated (with either eculizumab and/or anticoagulation). These analyses are limited due to small number of TE and mortality outcomes. Disclosures: Muus: Alexion Pharmaceuticals : Sat on advisory board of Alexion Pharmaceuticals. Other. Urbano-Ispizua:Alexion Pharmaceuticals, Inc: Membership on an entity's Board of Directors or advisory committees. Maciejewski:NIH: Research Funding; Aplastic Anemia & MDS International Foundation: Research Funding. Kanakura:Shire: Consultancy. Rosse:Alexion Pharmaceuticals, Inc: Consultancy, Membership on an entity's Board of Directors or advisory committees. Khursigara:Alexion Pharmaceuticals, Inc: Employment. Bedrosian:Alexion Pharmaceuticals: Employment, Equity Ownership. Hillmen:Alexion Pharmaceuticals, Inc: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees.

Abstract: Abstract 1525 Background: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare clonal hematopoietic stem cell disease characterized by complement-mediated hemolysis, a variable degree of bone marrow failure and thrombophilia, which may lead to reduced quality of life (QOL). There have been few reports of the disease burden of PNH from the patient's perspective. Aims: To describe patient-reported QOL, hospitalization, and missed work at time of PNH registry enrollment and to evaluate the association of these patient-reported outcomes (PROs) with demographics; patient reported symptoms (abdominal pain, chest pain and hemoglobinuria); and clinical characteristics (years since diagnosis, granulocyte clone size, underlying bone marrow disorder [BMD] and prior thrombotic event [TE] ). Methods: Enrollment data from 117 clinical sites participating in the observational PNH Registry in 16 countries on 5 continents was analyzed. Patients are included in the Registry if they have a PNH clone regardless of clone size, other BMD, symptoms, or treatments. As part of the study, patients are asked to complete questionnaires at enrollment including the six subscales of the EORTC QLQ-C30 (range=0-100, higher scores better) and the FACIT-Fatigue scale (range=0-52, higher scores better). Patients are also asked “in the past 6 months have you been admitted to a hospital for your PNH” and “in the past 6 months did you miss work as a result of PNH” (questions about work were added later in the study). Statistical analysis used ANOVA and Chi-square tests as appropriate. Results: As of August 2010 there were 657 patients enrolled in the Registry. Of these, 377 (57%) patients completed a baseline questionnaire (BQ) and are included in this analysis. Patients with and without a completed BQ were comparable on most study variables, although patients with a higher clone size were less likely to complete a BQ. Patients had a mean age of 45.8±17.6 years; 54% were female. Median PNH (granulocyte) clone size was 75% (nearly two-thirds had a clone size ≥50%), 45% had BMD (mostly aplastic anemia) and 12% had history of TE. Abdominal pain in the last 6 months was reported by 45% of patients, chest pain by 28%, and hemoglobinuria by 64%. Mean EORTC scores (general population reference in parenthesis) were: global health=64.4 (71.2), physical functioning=79.7 (89.8), role functioning=73.9 (84.7), emotional functioning=76.0 (76.3), cognitive functioning=81.1 (86.1), and social functioning=77.2 (87.5). Thus, scores for PNH patients were decreased by about 10% in 4 of the 6 subscales. PNH patients had a mean FACIT-Fatigue score of 36.6, while a general population reference is 43.6 (or a 16% reduction). PROs were independent of time since diagnosis, PNH clone size, or underlying BMD. Males reported better physical, emotional, and social functioning and less fatigue than females (all p 〈 .05). As expected, age strongly affected physical functioning (p 〈 .01). Patients with prior TE reported worse global health, physical, role, cognitive functioning, and more fatigue than patients without prior TE (all p 〈 .05). Patients reporting abdominal pain, chest pain, or hemoglobinuria had significantly worse EORTC and FACIT-fatigue scores on every scale (all p 〈 .05). Overall, 26% of patients had a PNH-related hospitalization in the past 6 months. Patients who reported TE, abdominal pain, chest pain, or hemoglobinuria were more likely to be admitted to the hospital (all p 〈 .05). There were 109 patients out of 244 (45%) who worked at a paid job. Of these,30% missed work in the past 6 months due to PNH. Patients were more likely to miss work if they had abdominal pain (47% vs 19%, p 〈 .01 or hemoglobinuria (42% vs. 7%, p 〈 .01). Conclusion: The disease burden to PNH patients is evident. Mean QOL is reduced in patients with PNH by 10 to 16% on most scales compared to the general population. One of four patients was hospitalized and 30% of patients with a paid job missed work due to PNH over a 6-month period. History of thrombosis and presence of PNH-related symptoms strongly affected QOL and hospitalization, while missed work was mostly impacted by symptoms. This global PNH Registry, which remains open to accrual (pnhregistry@iconplc.com), should help to redefine prospectively the long-term natural history of PNH, its treatments, and the outcomes of treatment, including outcomes measured from the patient's perspective. Disclosures: Muus: Celgene: Membership on an entity's Board of Directors or advisory committees; Alexion: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Szer:Alexion Pharmaceuticals, Inc.: Membership on an entity's Board of Directors or advisory committees. Schrezenmeier:Alexion Pharmaceuticals, Inc: Honoraria, Membership on an entity's Board of Directors or advisory committees. Brodsky:Alexion Pharmaceuticals, Inc: Membership on an entity's Board of Directors or advisory committees. Bessler:Alexion Pharmaceutical Inc: Consultancy; Novartis: Membership on an entity's Board of Directors or advisory committees; Taligen: Consultancy. Socié:Alexion: Honoraria, Membership on an entity's Board of Directors or advisory committees. Urbano-Ispizua:Alexion: Membership on an entity's Board of Directors or advisory committees. Maciejewski:Celgene: Research Funding; Eisai: Research Funding; Alexion: Consultancy. Rosse:Alexion: Consultancy, Membership on an entity's Board of Directors or advisory committees. Kanakura:Alexion: Membership on an entity's Board of Directors or advisory committees. Khursigara:Alexion Pharmaceuticals, Inc.: Employment, Equity Ownership. Karnell:Alexion Pharma International: Employment, Equity Ownership. Bedrosian:Alexion Pharmaceuticals, Inc.: Employment, Equity Ownership. Hillmen:Alexion Pharmaceuticals, Inc: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.

Abstract: Abstract 2241 Background: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare clonal hematopoietic stem cell disease characterized by complement-mediated hemolysis which can lead to life-threatening complications including thrombosis, kidney disease, pulmonary hypertension, pain, anemia, and severe fatigue. PNH clones occur in a number of patients with concomitant aplastic anemia (AA) and other bone marrow disorders (BMD). Some patients with PNH and/or BMD may require red blood cell (RBC) transfusions to treat anemia due to hemolysis or bone marrow hypoplasia. Aims: To characterize the use of RBC transfusions among PNH patients with and without underlying AA. Methods: Enrollment data from 117 clinical sites participating in the observational PNH Registry in 16 countries on 5 continents was analyzed. Patients are included in the Registry regardless of the proportion of cells with deficiency of glycosylphosphatidyl-inositol anchored proteins (GPI-AP), bone marrow pathology, symptoms, or treatments. Sites collect clinical history at enrollment and additional data every 6 months. Demographic data, use of transfusions and other treatments, lab results, and symptoms are summarized for PNH patients with and without AA. Results: As of June 30, 2010 there were 655 enrolled patients in the Registry (53% female, median age 43). At enrollment, 28% of patients had history of AA and 45% had no history of BMD. Patients with underlying AA had lower median GPI-AP deficient granulocytes than those without BMD (median = 53% vs. 86%, respectively, p 〈 .01) and patients in both groups had similar evidence of hemolytic activity when stratified by clone size (median LDH fold above normal upper limit was 0.90 vs. 0.94, p=.39 for patients with and without AA and clone size 〈 10%; median = 3.41 vs. 4.84, p=.08 for AA vs. no BMD and clone size ≥50%). Not all PNH patients required transfusions: 56% of all patients required transfusions in the year prior to enrollment. Although patients with and without AA were equally likely to be treated with blood transfusions in the year prior to study enrollment overall, some differences emerged when stratified by clone size. For patients with clone size 〈 50%, AA patients were almost twice as likely to receive transfusion in the previous year as patients without BMD (39% vs. 20%, p=.08). However, regardless of underlying AA, the proportion of patients receiving transfusions, in the prior year increased as clone size increased (29%, 31%, and 69% for clone sizes 〈 10%, 10–49%, and ≥50%, respectively, p 〈 .01). When patients were stratified by percent reticulocytes at enrollment (below vs. above the median value of 4.16%), 45% vs. 75% received transfusion in the prior year (p 〈 .01). Among patients receiving a transfusion in the year prior to enrollment, the mean number of RBC units transfused was 9.6 for patients with underlying AA and 7.9 for patients with no BMD (p=.10). However, approximately twice as many patients with AA received 20+ RBC units in that year compared to patients without BMD (20% vs. 11%, p=.09). Number of transfused units in that year was similar by clone size (mean 9.5 vs. 8.6 for clone size 〈 50% vs. ≥50%, p=.57). Concomitant treatment with anticoagulants or immunosuppressants was similar among patients who had received a transfusion in the past year compared to patients with no transfusions (39% vs. 33%, p=.13 and 26% vs. 22%, p=.25 respectively). Patients with AA had more bruising and bleeding while patients without BMD had more hemoglobinuria, dysphagia, and abdominal pain. Transfused patients with AA had more fatigue than non-transfused patients with AA (68% vs. 48%, p=.02). Conclusions: A substantial proportion (56%) of patients with PNH, but not all, required at least one transfusion in the year prior to enrolling in the registry, independent of underlying AA. The proportion of patients who had at least one transfusion increased with clone size. Among patients who had at least one transfusion, there was a trend for patients with underlying AA to receive more RBC units than patients without BMD. PNH patients with AA have fewer GPI-AP deficient granulocytes but demonstrate elevated hemolysis similar to patients without history of BMD when patients with similar clone sizes were compared. This Global PNH Registry, which remains open to accrual (pnhregistry@iconplc.com), should help to redefine prospectively the long-term natural history of PNH, its treatments, and the outcomes of treatment. Disclosures: Schrezenmeier: Alexion Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees. Brodsky: Alexion Pharmaceuticals, Inc.: Membership on an entity's Board of Directors or advisory committees. Muus: Celgene: Membership on an entity's Board of Directors or advisory committees; Alexion: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Bessler: Alexion Pharmaceutical Inc: Consultancy; Novartis: Membership on an entity's Board of Directors or advisory committees; Taligen: Consultancy. Szer: Alexion Pharmaceuticals, Inc.: Membership on an entity's Board of Directors or advisory committees. Maciejewski: Celgene: Research Funding; Eisai: Research Funding; Alexion: Consultancy. Socié: Alexion: Honoraria, Membership on an entity's Board of Directors or advisory committees. Urbano-Ispizua: Alexion: Membership on an entity's Board of Directors or advisory committees. Kanakura: Alexion: Membership on an entity's Board of Directors or advisory committees. Hoechsmann: Alexion: Speakers Bureau. Rosse: Alexion: Consultancy, Membership on an entity's Board of Directors or advisory committees. Khursigara: Alexion Pharmaceuticals, Inc.: Employment, Equity Ownership. Karnell: Alexion Pharma International: Employment, Equity Ownership. Bedrosian: Alexion Pharmaceuticals, Inc.: Employment, Equity Ownership. Hillmen: Alexion Pharmaceuticals, Inc: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.

Abstract: Abstract 2102 Background: Paroxysmal nocturnal hemoglobinuria (PNH) is a chronic, life-threatening hematopoietic stem cell disorder characterized by deficiency of the GPI-anchored complement inhibitory proteins CD55 and CD59. Uncontrolled complement activation is responsible for chronic hemolysis that leads to the serious clinical morbidities including thromboembolism (TE) and chronic kidney disease, which increase risk of mortality. PNH is infrequent in children and as such, there is a paucity of data in the literature examining their burden of disease. This is the largest series of pediatric patients with PNH, and the first comparison with adult PNH patients. AIM: To assess the clinical differences between pediatric and adult PNH patients with classic/hemolytic PNH. Methods: Data from 1143 PNH patients from 204 clinical sites in 21 countries on 5 continents (as of 6/30/11) were analyzed to evaluate clinical characteristics of PNH. Patients registered as having classic/hemolytic PNH were initially included (n=559). Of these, 62 additional patients were excluded due to either a 〈 30% granulocyte clone size, or missing data on enrollment date, date of birth, sex, date of disease start and history of TE. The final population for this study was 497 patients, classified into two groups, those first diagnosed at age 〈 18 years (pediatric patients N=49) and at age ≥18 years (adult patients N=448). Baseline demographics, laboratory values, PNH-related medical history, and physician-reported PNH symptoms were compared for pediatric and adult patients. Patients/guardians gave informed consent prior to enrollment. Results: The median age at disease start for pediatric patients was 15 years (5–17), and for adults was 33 years (18–87). Hemoglobin, leucocytes, neutrophils, reticulocytes, LDH, and number of transfusions were similar between both pediatric and adult patients. There were no differences in GPI-deficient granulocyte or RBC clone sizes between pediatric and adult patients. Follow-up was longer for children (mean + SD, in years: 14.5 + 13.6 vs 9.6 + 9.1, P 〈 0.001, respectively). The number of pediatric and adult patients receiving concomitant medications such as anticoagulants (peds 49% vs adults 54.9%; P=0.43) and eculizumab (peds 40.8% vs adults 45.5%; P=0.53) prior to enrollment were similar. No differences between pediatric and adult patients were observed in bone marrow disorders, renal impairment, hemoglobinuria, abdominal pain, dysphagia, headache and shortness of breath. In contrast, pediatric patients reported less fatigue (57.1% vs. 76.8%; P=0.001). TE incidence was 12.2% for pediatric and 23.9% for adults, which was statistically significant when the length of the time of exposure to this complication was taken into account; TE event rate was significantly lower in pediatric patients compared to adults (1.0/100 pt-yrs vs 4.4/100 pt-yrs; P 〈 0.001 by Poisson regression). Patients with TE had a mean granulocyte clone size of 85.7% vs 81.0% for patients without TE (P=0.026). Both in children and adults the risk of TE was much higher than expected for the general population (general pediatric population: TE incidence is 0.07 per 10,000 or 0.0007%, vs 12.2% in this study). TE events at venous sites (hepatic/portal, mesenteric/visceral, renal, and cerebral veins) and arterial sites were less frequent in pediatric patients compared to adults. The most striking difference in TE type was thrombophlebitis/deep vein thrombosis, which occurred significantly less frequently in pediatric than adult patients (2.0% vs 11.8%; p=0.037). In multivariate analysis, age 〉 18 years at disease onset and kidney disease were predictors of TE (odds ratio [OR] 3.01, 95% CI 1.15–7.72; P=0.02, and OR 1.87, 95% CI 1.03–3.4; P=0.04, respectively), while clone size was not a significant predictor of TE (OR 1.010, 95% CI 0.995–1.025; P=0.18). Conclusions: Pediatric PNH patients experience a significant burden of disease similar to adult PNH patients. There were no differences in LDH levels, GPI-deficient clone size, or in the incidence of bone marrow disorders, renal impairment, hemoglobinuria, abdominal pain, shortness of breath and dysphagia between pediatric and adult patients. TE event rate was lower in pediatric PNH patients when compared to adults, especially for those with concomitant kidney disease However, TE still remains an issue in this population and pediatric PNH patients are at significant risk for TE. Disclosures: Urbano-Ispizua: Alexion: Membership on an entity's Board of Directors or advisory committees. Schrezenmeier:Alexion Pharmaceuticals, Inc.: Membership on an entity's Board of Directors or advisory committees. Muus:Celgene: Membership on an entity's Board of Directors or advisory committees; Alexion: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Novarts: Membership on an entity's Board of Directors or advisory committees. Maciejewski:Celgene: Research Funding; Eisai: Research Funding; Alexion: Consultancy. Socié:Alexion: Honoraria, Membership on an entity's Board of Directors or advisory committees. Szer:Alexion Pharmaceuticals, Inc.: Membership on an entity's Board of Directors or advisory committees. Brodsky:Alexion Pharmaceuticals, Inc.: Membership on an entity's Board of Directors or advisory committees. Bessler:Alexion Pharmaceuticals, Inc.: Consultancy; Novartis: Membership on an entity's Board of Directors or advisory committees; Taligen: Consultancy. Rosse:Alexion: Consultancy, Membership on an entity's Board of Directors or advisory committees. Kanakura:Alexion: Consultancy, Membership on an entity's Board of Directors or advisory committees. Khursigara:Alexion: Employment, Equity Ownership. Bedrosian:Alexion Pharmaceuticals, Inc.: Employment, Equity Ownership. Hillmen:Alexion Pharmaceuticals, Inc.: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.