CEP-701 (Lestaurtinib) for Polycythemia Vera

Myelofibrosis is the gradual replacement of bone marrow (place where most new blood cells are produced) by fibrous tissue which reduces the body's ability to produce new blood cells and results in the development of chronic anemia (low red blood cell count). One of the main distinctions of myelofibrosis is "extramedullary hematopoesis", the migration or traveling of the blood-forming cells out of the bones to other parts of the body, such as the liver or spleen, resulting in an enlarged spleen and liver. Treatment for myelofibrosis is unsatisfactory and there is no medication that is specifically used in the treatment of myelofibrosis. There is a protein that is found to be present in the majority of myelofibrosis patients (JAK2) and the drug Lestaurtinib is being studied to see if it will stop this protein from functioning and thereby help control the disease. This study is divided into two Phases (1 & 2). In phase 1 we will be looking for the dose of study medication (Lestaurtinib) that will be the highest dose a patient can take without experiencing serious side effects, maximum tolerated dose (MTD). In phase 2, after the MTD dose has been established in phase 1, we will be investigating how well CEP-701 (Lestaurtinib) works at suppressing the protein (JAK2). The investigators also wish to find out important biologic characteristics or features of myelofibrosis through an additional correlative biomarker study (MPD-RC #107). The correlative biomarker study is a study that is related to the main study, but is looking to answer different questions than the main study. The purpose of the biomarker study is to understand the causes of MPD and to develop improved methods for the diagnosis and treatment of these diseases, while the main study is trying to find out how well CEP-701 (Lestaurtinib) will work in treating the myeloproliferative disease.