The purpose of this Phase 2 study is to evaluate the efficacy and safety of momelotinib (MMB) in combination with luspatercept (LUSPA) in participants with transfusion dependence (TD) primary myelofibrosis (PMF) or Post-polycythemia vera (PV)/ essential thrombocythemia (ET) myelofibrosis (MF) who are either janus kinase (JAK) inhibitor (JAKi) naïve or experienced.
Is age ≥18 years.
Confirmed diagnosis of PMF in accordance with the World Health Organization (WHO) 2016 criteria, or Post-PV/ET myelofibrosis in accordance with the International Working Group-Myeloproliferative Neoplasms Research and Treatment (IWG-MRT) criteria.
JAKi naïve or previously treated with either ruxolitinib or fedratinib for PMF or Post-PV/ET myelofibrosis for ≥90 days, or ≥28 days if JAKi therapy is complicated by RBC transfusion requirement of ≥4 units in 8 weeks, or Grade 3/4 AEs of thrombocytopenia, anemia, or hematoma.
High risk, intermediate-2, or intermediate-1 risk as defined by Dynamic International Prognostic Scoring System (DIPSS) [Passamonti, 2010] or DIPSS-plus [Gangat, 2011].
History of intestinal disease, inflammatory bowel disease, major gastric surgery, or other gastrointestinal conditions (e.g., uncontrolled nausea, vomiting, malabsorption syndrome) likely to alter absorption of study intervention or result in inability to swallow oral medications.
Participants with an invasive malignancy or history of invasive malignancy other than the disease under study within the last 5 years.
Known clinically significant anemia due to iron, vitamin B12, or folate deficiencies, or autoimmune or hereditary hemolytic anemia, gastrointestinal bleeding, or thalassemia.
Active uncontrolled infection (participants receiving outpatient antibacterial and/or antiviral treatments for infection that is under control or as infection prophylaxis may be included in the trial);