Luspatercept versus Placebo in Subjects with Myeloproliferative Neoplasm-Associated Myelofibrosis

Primary myelofibrosis is a condition characterized by the buildup of scar tissue (fibrosis) in the bone marrow, the tissue that produces blood cells. Because of the fibrosis, the bone marrow is unable to make enough normal blood cells. The shortage of blood cells causes many of the signs and symptoms of primary myelofibrosis. 

This research study is for patients diagnosed with anemia due to myeloproliferative neoplasm (MPN)-associated myelofibrosis who are also receiving treatment with a Janus Kinase 2 (JAK2) inhibitor. Treatment with a JAK2 inhibitor is used to help treat various symptoms of MPN-associated myelofibrosis.  

Luspatercept is a soluble, recombinant fusion protein that enhances red blood cell production and prevents anemia. The main purpose of this study is to see if people with MPN-associated myelofibrosis that need blood transfusions will stop needing RBC transfusions or require less frequent RBC transfusions by taking luspatercept.

If you agree to participate in this study, you may get luspatercept or placebo, plus best supportive care regardless of which treatment you will receive. Best supportive care will always be provided throughout your participation in this study. Your time on the study treatment can range from approximately 24 weeks (6 months) to when the study doctor determines you stop receiving benefit from the study treatment or your MPN-associated myelofibrosis worsens. The anticipated time you will be on the study, if you do not discontinue early, will be approximately 5 years.

During study visits, you will be asked to get subcutaneous injections (under the skin) of luspatercept or placebo on Day 1 of every 21 day cycle, have blood samples drawn and complete quality of life questionnaires on electronic devices. This study also includes testing of blood and saliva samples for biomarkers. Biomarkers are substances in your body such as proteins that can be used to show the status of your disease and may tell us how the study treatment is working in your body. You cannot participate in the study if you do not agree to participate in the biomarker testing.

In order to participate you must meet the following criteria:

• Are 18 years of age or older and have a diagnosis of primary myelofibrosis (PMF), post-essential thrombocythemia (post-ET) or post-polycythemia vera myelofibrosis (post-PV MF).
• Require frequent red blood cell (RBC) transfusions.
• Are receiving continuous JAK2 inhibitor therapy for the treatment for myeloproliferative neoplasm (MPN)-associated myelofibrosis (MF) as part of your standard-of-care therapy for at least 32 weeks.

You will be excluded from the study if any of the following criteria apply to you:

• Have anemia from a cause other than MPN-associated MF or JAK2 inhibitor therapy.
• Have had prior treatment with hydroxyurea, immunomodulatory compounds such as pomalidomide, thalidomide, ESAs, androgenic steroids or other drugs with potential effects on the production of blood cells 8 weeks or less before study entry.
• Have uncontrolled hypertension, inadequately controlled heart disease, have had a prior hematopoietic cell transplant, or have had a stroke, myocardial infarction, deep venous thrombosis, pulmonary or arterial embolism within 6 months.
• Have received prior treatment with luspatercept or sotatercept.

This is a partial list of eligibility requirements. To inquire about your eligibility, please call the contact number provided. If you wish to inquire via email, please include the title of the study in your message.