Burden of Disease

Approximately 60% of patients with myelofibrosis (MF) are anemic and 45% are transfusion dependent within 1 year of diagnosis, with most progressing to transfusion dependency over time. Transfusion dependency and moderate to severe anemia are critical negative prognostic factors in MF and inversely correlated with quality of life.

Anemia and transfusion dependency represent significant unmet medical needs in MF and, other than frequent transfusions, there are limited treatment choices for patients. The two approved JAK inhibitors for the treatment of MF have been shown to exacerbate anemia and may require dose reductions for patients with moderate to severe anemia.

For most transfusion-dependent MF patients, transfusions remain the only viable treatment option despite the fact recurrent transfusions provide no improvement in overall survival. Transfusions represent a substantive burden both to the patient and healthcare systems, with significant risk of complications, leading to a significant impact on both quality of life and overall survival in MF.

The optimal drug therapy for MF would address disease-related cytopenias, including anemia and transfusion dependency, while also improving splenomegaly and symptoms.