Momelotinib During and After HCT in Myelofibrosis

This is a single-center, open-label, phase I study to determine the safety and tolerability of momelotinib in patients with myelofibrosis during and after hematopoietic cell transplantation (HCT).

The purpose of this study is to test the safety, effects, and recommended dose of an investigational drug, momelotinib, during and after undergoing allogeneic HCT. This study will enroll up to 28 participants with myelofibrosis that are planned to undergo standard of care allogeneic hematopoietic cell transplantation (HCT). Participants may receive momelotinib or other JAK inhibitors prior to HCT and may adjust momelotinib dosing per protocol as follows: Multiple dose cohorts (100 mg daily, 150 mg daily and 200 mg daily) will be investigated in the peri-transplant period. Participants not previously on momelotinib will begin this drug at the initiation of conditioning therapy (Day -7 from HCT). Once participants have achieved hematopoietic recovery and are at least Day 21(cycle 2 day 1) after HCT, participants, receiving lower doses will increase the dose to 200 mg daily. Patients will remain on momelotinib for a total of 13 cycles (28 days per cycle, until approximately 1 year after transplant). After HCT, participants will be followed for up to 2 years.