A Phase 3, Randomized, Double-Blind, Active-Control Study of Pelabresib (DAK539) and Ruxolitinib vs. Placebo and Ruxolitinib in Adult Patients with Myelofibrosis who are JAK inhibitor naive

The purpose of this study is to find out whether taking pelabresib together with ruxolitinib works better than taking ruxolitinib alone in adults with myelofibrosis, a rare blood cancer that affects the bone marrow. Ruxolitinib is approved by the U.S. Food and Drug Administration (FDA) for the treatment of myelofibrosis, while pelabresib is an investigational drug that has not been approved by the FDA. The study will compare whether the combination treatment can better reduce spleen size and improve myelofibrosis-related symptoms than ruxolitinib alone. Participants will be randomly assigned (like flipping a coin) to receive either pelabresib plus ruxolitinib or a placebo plus ruxolinib, where a placebo is a drug that looks like the study drug but does not contain any active medication.

Are you Eligible? (Inclusion Criteria)

• must be at least 18 years of age - have a diagnosis of primary myelofibrosis (PMF) or post-polycythemia vera MF or post-essential thrombocythemia MF (Post-PV/ET MF) - must not have had prior treatment with any Janus kinase (JAK) inhibitor or bromodomain and extraterminal (BET) inhibitor