Myelofibrosis Treated With Pacritinib Before aSCT. (HOVON134MF)

Inclusion Criteria: * Patients with a confirmed diagnosis of post-ET, post-PV or primary myelofibrosis * Intermediate-2 or high-risk according to DIPSS plus (Appendix E) * Age 18-70 years inclusive * WHO performance status 0-2 (Appendix C) * All men and women of childbearing potential must agree to use adequate contraception during the study * Written informed consent * Patient is capable of giving informed consent Exclusion Criteria: * Previous treatment with JAK2 inhibitors within 2 weeks of study inclusion. Patients who have been treated with pacritinib as their previous JAK2 inhibitor treatment cannot participate in this study * Any GI or metabolic condition (e.g. inflammatory or chronic functional bowel disorder such as Crohn's Disease, Inflammatory Bowel Disease, chronic diarrhea or constipation) that could interfere with absorption of oral medication * Left ventricular cardiac ejection fraction of ≤ 45% by echocardiogram or multigated acquisition (MUGA) scan * Impaired liver and renal function, defined by liver transaminases (aspartate aminotransferase \[AST\]/serum glutamic oxaloacetic transaminase \[SGOT\] and alanine aminotransferase \[ALT\]/serum glutamic pyruvic transaminase \[SGPT\]), \>3 × the upper limit of normal (ULN) (AST/ALT \>5 × ULN if transaminase elevation is related to MF), direct bilirubin \>4× ULN, and creatinine clearance ˂ 40 ml/min. * Impaired coagulation function, defined by prothrombin time (PT)/international normalized ratio (INR), partial t…