A Global Registry of Patients with Paroxysmal Nocturnal Hemoglobinuria.

Abstract 3007

Poster Board II-983

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, and pulmonary hypertension. The natural history of PNH is highly variable and has previously been captured by retrospective assessment. However, the clinical presentation and prognosis of the disease has changed with the increased awareness of PNH, the increased use of more sensitive diagnostic tests, and the availability of new treatment. Specifically, the development of targeted but potentially life-long therapies, such as terminal complement blockade, necessitates the collection of long-term outcomes data in this patient population. We have established a global PNH Registry in order to redefine the natural history of PNH capturing a wide range of patients from all over the world. The goal of the present analysis is to describe the data collected for the patients in the Registry and demonstrate its use as an ongoing repository of information on symptoms, course, complications and treatment in patients with a PNH clone. The first patient was enrolled in January 2005, with data contributed from 62 clinical sites in 12 countries on 4 continents as of July 2009. Patients are included in the Registry regardless of amount of clone, bone marrow pathology, symptoms, or treatments. Sites collect data at enrollment and every 6 months including demographics, diagnostics and flow cytometry, other lab tests including LDH, medical conditions such as bone marrow pathology and major adverse vascular events (MAVE), clinical symptoms, medications and transfusions, qualitative assessments, bone marrow transplant, and mortality. Patients complete a questionnaire every 6 months including health-related quality-of-life, symptoms, and use of health care services. As of July 2009 there were 368 enrolled patients in the Registry (51% female, 49% male). Mean age at enrollment was 43.6 ±16.7, while mean age at first PNH symptoms was 35.9±16.7. At enrollment, median GPI-deficient granulocyte percentage (GPI-DG) was 80.4%, while 10% of patients had a GPI-DG <10. Of those patients with a GPI-DG <10, 81% had bone marrow pathology (62% with aplastic anemia, 16% with myelodysplastic syndrome, 3% other pathology) compared to 38% of patients with GPI-DG ³50. MAVE was increased in patients with GPI-DG ³50 compared to <10 (22% vs. 8%), as were LDH levels (median 1042 vs. 239 U/L). Patients with GPI-DG <10 reported high levels of significant clinical symptoms (fatigue 59%; dyspnea 52%; abdominal pain 41%) and symptom reporting was generally increased in patients with higher GPI-DG levels. Treatment in the year prior to Registry enrollment primarily consisted of transfusions (42%), anticoagulation therapy (30%), eculizumab (29%), and immunosuppression (23%), although these varied by GPI-DG level. Clinicians assessed 14% of patients with a Karnofsky score of 70 or lower (i.e., not capable of work or normal activity). Patients' assessment of their overall health, social functioning, and fatigue worsened and use of health care services increased with higher GPI-DG. At this time, median follow up is 12.8 months, although 25% of patients have been followed for at least 30 months. Two patients received a bone marrow transplant and 8 are deceased. In conclusion, preliminary data show that greater GPI-DG is associated with less underlying bone marrow pathology, more hemolysis, more thromboses, and more patient-reported symptoms. New clinical sites and geographic regions are encouraged to participate in the Registry (pnhregistry@iconplc.com). This global PNH Registry should help to redefine prospectively the long-term natural history of PNH, its treatments, and the outcomes of treatment.