Received JAK inhibitor therapy after allo-HSCT for any indication. Treatment with a JAK inhibitor before allo-HSCT is permitted.
CRLF rearrangement with JAK or JAK mutation (JAK+)
CRLF rearrangement without JAK mutation
Other JAK pathway alterations (eg, JAK fusions, erythropoietin receptor (EPO-R) fusions, SHB deletions, interleukin- receptor-alpha (ILRA) mutations) with or without CRLF rearrangement
Patients who have previously been treated with an IL-, JAK or STAT inhibitor for any indication, such as ruxolitinib or tocilizumab
Participants who were treated with prior JAK inhibitors for aGvHD; except when the participant achieved complete or partial response and has been off JAK inhibitor treatment for at least  weeks prior to Cycle  Day 
Patients previously treated with a Janus kinase (JAK) inhibitor
Hypersensitivity to any JAK inhibitor
Prior treatment with JAK inhibitor therapy is not excluded. Patients on a JAK inhibitor may continue through conditioning until day - then tapered at the discretion of the investigator.
Patients must not have received prior JAK inhibitor therapy.
Prior treatment with JAK inhibitor therapy is not excluded; a JAK inhibitor will need to be stopped - days prior to starting conditioning regimen
Subjects who have previously received JAK inhibitor therapy
Treatment with ruxolitinib or other JAK inhibitor in the past
Any previous use of Janus kinase (JAK) inhibitor, osimertinib, or other EGFR-directed therapy for TM-mt NSCLC.
PART : Received JAK inhibitor for at least  weeks immediately prior to conditioning and be able to continue until Day - pre-transplant
Patients cannot have any other form of chemotherapy for their MPN (other than hydroxyurea); specifically prior interferon or JAK inhibitors are prohibited
Any previous Janus kinase  gene (JAK) inhibitor treatment prior to study enrollment, with the exception of ruxolitinib
Hypersensitivity to Janus kinase (JAK) inhibitor
Documented progressive disease during or after JAK inhibitor therapy
Received Janus kinase inhibitor therapy after allo-HSCT for any indication. Treatment with a JAK inhibitor before allo-HSCT is permitted.
MF PATIENTS: Patients must be intermediate I risk or beyond and meet the following:\r\n* In need of treatment\r\n* Intolerant or refractory to ruxolitinib (or other investigational Janus kinase [JAK]-inhibitors) OR unlikely to benefit from ruxolitinib\r\n* Ineligible or refusal to undergo stem cell transplantation
Any prior or concomitant use of another JAK inhibitor
Previously received JAK inhibitor therapy for any indication.
Prior use of a JAK or JAK inhibitor
Patients must be resistant to, intolerant of, or ineligible for Janus kinase (JAK) inhibitor therapy, or have refused such therapy
History of prior janus kinase (JAK) or STAT inhibitor treatment
Previous allergic reactions to janus kinase (JAK) inhibitors or excipients
Prior therapy with ruxolitinib or other JAK inhibitors
Any chemotherapy (e.g., hydroxyurea), immunomodulatory drug therapy (e.g., thalidomide), immunosuppressive therapy, corticosteroids >  mg/day prednisone or equivalent, growth factor treatment (e.g., erythropoietin) or Janus kinase (JAK) inhibitor therapy =<  days prior to registration
Any prior therapy with JAK-tyrosine kinase inhibitor (TKI), hypomethylating agents, histone deacetylase inhibitor (HDACI), mechanistic target of rapamycin inhibitor (mTORi), or immunomodulatory drugs (iMiDs) is allowed as long as it is greater than  weeks since last dose of administration and in the case of a JAK-TKI or HDACI that discontinuation was not due to non-hematologic drug toxicity; an exception to this criteria are patients currently on at least mg BID of ruxolitinib for greater than  months and who have not shown an optimal response (i.e. without % reduction in palpable splenomegaly or % reduction in symptom burden); with a reduction of ruxolitinib to mg BID these patients may enter onto the study without stopping ruxolitinib
MF patients must have received prior JAK inhibitor therapy, and been found to be intolerant, or refractory/relapsed from prior JAK inhibitor therapy, based on investigator assessment
Subjects previously treated with anagrelide or JAK inhibitors.
Prior treatment with a JAK inhibitor for any indication.
Subjects with any prior exposure to Janus kinase  (JAK) inhibitor therapy (i.e. ruxolitinib or prior pacritinib therapy) are excluded
Prior treatment with a JAK inhibitor for any indication.
Prior treatment with more than  JAK inhibitors or with pacritinib
There is no maximum cumulative prior JAK inhibitor treatment
BTK/SYK/JAK/PIK inhibitors
Treatment with a Janus kinase (JAK) inhibitor within  days of the planned first dose of MMB
Hypersensitivity to Janus kinase (JAK) inhibitor
Prior therapy with a janus kinase  (JAK) or fms-related tyrosine kinase  (FLT) inhibitor
Prior therapy with a JAK inhibitor (other than ruxolitinib for less than  months duration and currently on it) or histone deacetylase inhibitor (HDACi); patients that are currently on ruxolitinib for less than  months of therapy are eligible
Patients who have received prior treatment with JAK inhibitor
Patients must be off myeloproliferative neoplasm (MPN) directed therapy, such as Janus kinase (JAK)-inhibitors, for at least  weeks prior to administration of the study drug; NOTE: This does not include supportive transfusion, or hydroxyurea; these must be stopped prior to first day of treatment, but no wash out period is required
Patients must be resistant to, intolerant of, or ineligible for JAK inhibitor therapy, based on severe anemia or thrombocytopenia
Prior treatment with more than two Janus kinase  (JAK) inhibitors or with pacritinib
Moderate or severe cGVHD diagnosed and staged per National Institute of Health (NIH) criteria; responses to Janus kinase (JAK) inhibitors have not been restricted to specific organs, so any organ involvement is eligible
Hypersensitivity to JAK inhibitors
Subjects who have previously received JAK inhibitor therapy
Part B only: Prior treatment with SYK or Janus Kinase (JAK) inhibitors, except MF subjects.
Prior treatment with a JAK inhibitor or with an investigational agent, device, or procedure within  days of enrollment.
Myeloproliferative neoplasms (MPN): must have < % peripheral / marrow blasts\r\n* Note: Prior use of a Janus kinase  (JAK) inhibitor is allowed up to  weeks before day  of allogeneic hematopoietic cell transplantation (alloHCT)
Any patient anticipating or scheduled to receive a tyrosine kinase inhibitor, FLT inhibitor, or JAK inhibitor (outside of this study) post-HCT