Alexion launches EXPLORE study for severe anemia disorder

07-17-2006

With research suggesting that many patients with Paroxysmal Nocturnal Hemoglobinuria (PNH) go undiagnosed for years and that many patients have PNH in association with bone marrow failure disorders, Alexion Pharmaceuticals (ALXN) announced the initiation of the multicenter EXPLORE study to examine the frequency of PNH in patients with aplastic anemia (AA), myelodysplastic syndrome (MDS) and other bone marrow failure disorders.

Although the hemolytic blood disorder PNH is associated with bone marrow disorders, it is often misdiagnosed or undetected in these patients.

Current published guidelines recommend that patients with aplastic anemia, refractory anemia-myelodysplastic syndromes, and patients with any one of the following - venous thrombosis involving unusual sites, hemoglobin in the urine, intravascular hemolysis without antibodies, or episodic abdominal or swallowing pain and hemolysis - should be screened for PNH. The test for PNH requires only a small sample of the patient's blood from a vein in the arm.

The EXPLORE (EXamination of PNH, by Level Of CD59 on Red and white blood cells, in bone marrow failure syndromes) study expects to engage approximately 200 hematologists to enroll an estimated 2000 patients. Patients with any evidence of AA, MDS, or other bone marrow failure disorders will be asked to give informed consent to enter into the study's screening phase.

The trial will mark the first systematic effort to determine the presence of the PNH blood cell clone in patients with AA, MDS, or other bone marrow failure disorders. Enrollment is expected to begin this summer in the U.S. and is then expected to expand to Europe and Asia.

PNH is a rare, severe anemia that is associated with significant morbidity and early mortality. Based upon scientific investigations and presentations of the prevalence of patients diagnosed with abnormal PNH cells in their blood, it is currently estimated that approximately 8,000-10,000 people in North America and Western Europe suffer from PNH. It is caused by a hematopoietic stem cell mutation resulting in a deficiency of CD59, a complement inhibitor protein that blocks the formation of the terminal complement complex on the blood cell surface and prevents hemolysis.

The mean age of onset is about 30- 40 years of age and approximately 10% of all newly diagnosed patients are 21 or younger. The PNH phenotype may arise in early progenitor stem cells as a rescue attempt for failed bone marrow, and many patients are totally dependent on these cells for survival. PNH symptoms include intravascular hemolysis, hemoglobinuria and thrombosis. The most common symptoms at initial presentation include anemia, hemoglobinuria, bleeding, gastrointestinal symptoms, jaundice, or blood clots.

"Alexion is committed to expanding awareness and increasing the community's knowledge about this debilitating and often life-threatening disease to physicians and patients," said Leonard Bell, MD, CEO of Alexion. "With these new initiatives, we hope to further clinical understanding of PNH and its association with disorders of bone marrow failure, and ensure that all patients with PNH receive an accurate diagnosis. At the same time, we look forward to providing a valuable resource and an opportunity for collaboration and communication through our Web site."

The EXPLORE study will enroll patients 18 and older with evidence of AA, MDS syndromes (refractory anemia, refractory anemia with ringed sideroblasts, refractory cytopenia with multilineage dysplasia, refractory cytopenia with multilineage cysplastia and ringed sideroblasts, refractory anemia with excess blasts (type 1 and 2), unclassified MDS and 5q-syndromes), as well as other bone marrow failure disorders. An initial peripheral blood draw will be used for hematological evaluation. Patients who test positive for the PNH clone may be asked to participate in a 2-year follow-up to monitor symptoms and conduct hematological assessments.

This article was prepared by Biotech Business Week editors from staff and other reports. Copyright 2006, Biotech Business Week via NewsRx.com.