Background
Myelofibrosis
MYELOFIBROSIS
Myelofibrosis (MF) is a chronic, The small-molecule JAK1 and JAK2 inhibitor (JAKi) ruxolitinib (RUX) was a first-in-class drug and has significantly altered the treatment of MF since its approval in 2011/2012. Prior to this, only hydroxyurea and older drugs such as pipobroman or busulfan had been available for patients (patients) who were not eligible for allogeneic transplantation, and prognosis of high-risk patients was poor.RUX was approved in the United States (U.S.) in 2011 and in the European Union (EU) in 2012 following the results of two pivotal, randomized, phase III trials (the COMFORT-I and -II trials). In both studies, patients receiving RUX exhibited significant reductions in spleen volume and symptom burden [A global expanded access clinical trial, termed JUMP, was conducted to provide expanded access to RUX following approval until the drug became fully available. The final results of this trial have been published [Comparison of main inclusion and exclusion criteria from the JAKoMo, JUMP, and both COMFORT trials [Abbreviations: The JAKoMo clinical trial (a prospective, two-arm, non-interventional study of RUX in patients with MF) was established in 2012 as a post-authorization, non-interventional, phase IV study and includes two different cohorts of patients: patients who were RUX naïve (Arm A) and those who were already receiving RUX (Arm B). Patients were included according to the drug label without any further restrictions or further inclusion/exclusion criteria. Hence, JAKoMo patients constitute a representative sampling of real-world patients receiving RUX. This is an interim analysis, focusing on RUX-naïve patients only (Arm A), with a median of 1.5 years of follow-up, reporting “real-world” data from RUX-treated MF patients.