Myelofibrosis (MF) is a clonal disorder of the pluripotent hematopoietic stem cell, whose clinical manifestations can be extremely heterogeneous, including cytopenias, organomegaly, constitutional symptoms, and cachexia. Median survival ranges from approximately 3.5 to 5.5 years; while the most frequent cause of death is the evolution to acute myeloid leukemia, also other conditions such as progression without transformation, complications due to cytopenias including infections or bleeding, and cardiovascular events may be fatal. Myelofibrosis is still orphan of curative treatments: allogeneic hematopoietic stem cell transplant (HSCT), the only therapeutic approach that has clearly demonstrated an impact on disease progression, is associated with relevant morbidity and mortality and only a minority of patients is eligible for such an intensive procedure. While the discovery of the crucial role of JAK2 mutations and the consequent clinical use of JAK inhibitors has led to a dramatic improvement of symptoms control and quality of life, yet these drugs do not significantly modify the natural history of the disease. A better understanding of the molecular pathogenesis will hopefully foster the development of new targeted therapies aimed at improving MF prognosis. Herein, we review the most recent advances about JAK inhibitors and other molecules which are under investigation.
Keywords: Fedratinib; Momelotinib; Myelofibrosis; Pacritinib; Ruxolitinib; Target therapy.