Background and Objectives

This Phase 1/2 trial will administer INCB000928 as monotherapy or in combination with ruxolitinib to improve transfusion‑dependent anemia in patients with myelofibrosis (MF). MF is a rare hematologic malignancy characterized by suppressed hematopoiesis, and current therapeutic options are limited. Consequently, evaluating a drug with a novel mechanism holds significant importance for enhancing patient quality of life.

Study Design

The study will be conducted as an open‑label trial and consists of a dose‑escalation phase followed by an expansion phase. Primary assessments include safety and tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and efficacy, with the number of transfusions required and hemoglobin increase designated as the primary endpoints. This design aims to rapidly identify the optimal dose and response in early development.

Current Therapies and Differentiation

Current management of MF‑related anemia primarily involves ruxolitinib monotherapy or adjunctive agents such as erythropoietin (EPO) formulations. INCB000928 is a candidate targeting a novel pathway, and its combination with existing JAK inhibitors is expected to produce synergistic effects. The differentiated mechanism of action may benefit patient subgroups that are refractory to standard therapies.

Market and Clinical Impact

MF is a rare disease affecting several thousand patients annually, with a substantial unmet need for anemia management. Successful trial outcomes could establish a new therapeutic paradigm that includes INCB000928 and expand the market for ruxolitinib‑based combination regimens. Conversely, even if the trial fails, mechanistic validation data could be leveraged for development in other indications.