Reduced Intensity Haploidentical Transplantation for the Treatment of Primary or Secondary Myelofibrosis

Phase 2

Recruiting

Conditions: Primary Myelofibrosis
Secondary Myelofibrosis

Interventions: Drug: Cyclophosphamide
Drug: JAK Inhibitor
Drug: Fludarabine
Biological: Recombinant Granulocyte Colony-Stimulating Factor
Drug: Melphalan
Drug: Mycophenolate Mofetil
Procedure: Peripheral Blood Stem Cell Transplantation
Drug: Tacrolimus
Radiation: Total-Body Irradiation
Procedure: Computed Tomography
Procedure: Magnetic Resonance Imaging
Procedure: Bone Marrow Biopsy
Procedure: Bone Marrow Aspiration
Procedure: Biospecimen Collection
Procedure: Echocardiography
Procedure: Multigated Acquisition Scan

Registration Number: NCT04370301

Lead Sponsor: Fred Hutchinson Cancer Center

Brief Summary: This initial cohort of this phase II trial studied the outcomes of using a JAK inhibitor prior to reduced intensity haploidentical (Haplo) transplantation for the treatment of primary or secondary myelofibrosis (MF). The primary risk of using Haplo HCT in patients with MF is graft failure. In the first cohort, all patients engrafted. There were no instances of graft failure. However, a large number of patients did have graft versus host disease as a complication of their transplant. JAK inhibitors have since been approved for the indication of graft versus host disease treatment. And we are also using them for graft versus host disease prevention in a study of MF patients with sibling and unrelated donors. Therefore, we are opening a new cohort of the current study using the JAK inhibitor prior to, during and after Haplo transplant. Our goal is to decrease graft versus host disease in patients receiving a Haplo MF transplant without increasing the risk of graft failure.

Detailed Description: OUTLINE: Cohort 1 is now closed and all patients will be enrolled on Cohort 2.

COHORT I:

JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of hematopoietic cell transplantation (HCT) conditioning through day -4 before transplantation.

CONDITIONING: Patients receive melphalan intravenously (IV) over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo total-body irradiation (TBI) on day -1 or day -1 and day 0.

TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0.

GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then orally (PO) for about 6 months, mycophenolate mofetil PO twice daily (BID) or three times daily (TID) beginning day 5 for 6 weeks, and granulocyte colony-stimulating factor (G-CSF) subcutaneously (SC) beginning day 7 until neutrophil recovery is \> 1,500/mm\^3.

COHORT II:

JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day +5 through 9-12 months after transplant.

CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0.

TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0.

GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3.

All patients undergo magnetic resonance imaging (MRI), computed tomography (CT), bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo echocardiography (ECHO) or multigated acquisition scan (MUGA) on the trial.

After completion of study treatment, patients are followed up between day 80-100, at 1 year, and then up to 5 years.

Recruitment & Eligibility

Status: RECRUITING

Sex: All

Target Recruitment: 20

Inclusion Criteria

PART 1: JAK INHIBITOR ADMINISTRATION INCLUSION CRITERIA
Age > 18 years
Diagnosis of primary myelofibrosis (PMF) as defined by the 2016 World Health Organization classification system or diagnosis of secondary MF as defined by the International Working Group (IWG) for Myeloproliferative Neoplasms Research and Treatment criteria
Patients meeting the criteria for intermediate-1, intermediate-2 or high-risk disease by the Dynamic International Prognostic Scoring System (DIPSS)-plus scoring system (DIPSS may be used if all data from DIPSS are not available)
Ability to understand and the willingness to sign a written informed consent document (or legally authorized representative)
Patient must be a potential hematopoietic stem cell transplant candidate
PART 2: ALLOGENEIC STEM CELL TRANSPLANT INCLUSION CRITERIA
Meeting criteria for 1st phase as above, at time of initiation of JAK inhibitor, including ability to understand and willingness to sign a written informed consent (or legally authorized representative). Patients arriving to our institution for transplant and not enrolled in Part 1 may still be enrolled in Part 2 if Part 1 criteria met. These patients will have Part 1 endpoints transcribed from medical records
Received JAK inhibitor for at least 8 weeks immediately prior to conditioning and be willing to continue until 9-12 months post-transplant as tolerated
Karnofsky performance status score >= 70
Calculated creatinine clearance using the Cockcroft-Gault formula or 24 hour (hr) urine creatinine clearance must be > 60 ml/min
Total serum bilirubin must be < 3 mg/dL unless the elevation is thought to be due to Gilbert's disease or hemolysis
Transaminases must be < 3 x the upper limit of normal
Patients with clinical or laboratory evidence of liver disease will be evaluated for the cause of liver disease, its clinical severity in terms of liver function, and the degree of portal hypertension. Patients with fulminant liver failure, cirrhosis with evidence of portal hypertension or bridging fibrosis, alcoholic hepatitis, hepatic encephalopathy, or correctable hepatic synthetic dysfunction evidenced by prolongation of the prothrombin time, ascites related to portal hypertension, bacterial or fungal abscess, biliary obstruction, chronic viral hepatitis with total serum bilirubin > 3 mg/dL, and symptomatic biliary disease will be excluded
Diffusion capacity of the lung for carbon monoxide (DLCO) corrected > 60% normal; may not be on supplemental oxygen
Left ventricular ejection fraction > 40% OR shortening fraction > 26%
Comorbidity Index < 5 at the time of pre-transplant evaluation
DONOR: Patients must be screened prior to transplant for donor-specific anti-HLA antibodies (DSA). Patients with DSA will be reviewed by the principal investigator and considered for desensitization treatment
DONOR: Children are preferred over siblings and parents
DONOR: Younger donors are preferred over older donors
DONOR: ABO matched donors are preferred over minor ABO mismatched and over major ABO mismatch donors

Exclusion Criteria

PART 1: JAK INHIBITOR ADMINISTRATION EXCLUSION CRITERIA
Contraindication to receiving a JAK inhibitor including:
- Patients who have known hypersensitivity to JAK inhibitors
- Clinical or laboratory evidence of significant renal or hepatic impairment including cirrhosis
- Active uncontrolled infection
- Known human immunodeficiency virus (HIV) positivity
- Women who are pregnant or trying to conceive
- Caution should be used in patients with platelets < 100 though adjustments in dose can be made to accommodate anyone with platelets > 50
History of prior allogeneic transplant
Leukemic transformation (> 20% blasts)
PART 2: ALLOGENEIC STEM CELL TRANSPLANT EXCLUSION CRITERIA
Uncontrolled viral or bacterial infection at the time of study enrollment
Active or recent (prior 6 month) invasive fungal infection without infectious disease (ID) consult and approval
Known HIV positivity
Pregnant or breastfeeding
Availability of an human leukocyte antigen (HLA)-identical or 1-allele-mismatched related donor or an HLA 10 of 10 matched unrelated donor

Study & Design

Study Type: INTERVENTIONAL

Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Total-Body Irradiation	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	JAK Inhibitor	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Echocardiography	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Recombinant Granulocyte Colony-Stimulating Factor	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Peripheral Blood Stem Cell Transplantation	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Computed Tomography	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Recombinant Granulocyte Colony-Stimulating Factor	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Bone Marrow Biopsy	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Bone Marrow Aspiration	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Magnetic Resonance Imaging	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Biospecimen Collection	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Multigated Acquisition Scan	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Fludarabine	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	JAK Inhibitor	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Computed Tomography	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Peripheral Blood Stem Cell Transplantation	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Total-Body Irradiation	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Magnetic Resonance Imaging	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Bone Marrow Aspiration	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Bone Marrow Biopsy	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Biospecimen Collection	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Echocardiography	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Multigated Acquisition Scan	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Cyclophosphamide	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Fludarabine	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Melphalan	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Mycophenolate Mofetil	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort I (JAK inhibitor, conditioning, GVHD prophylaxis)	Tacrolimus	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Cyclophosphamide	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Mycophenolate Mofetil	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Melphalan	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.
Cohort II (JAK inhibitor, conditioning, GVHD prophylaxis)	Tacrolimus	JAK INHIBITOR THERAPY: Patients receive a JAK inhibitor at least 8 weeks prior to the start of HCT conditioning through day -4 before transplantation. Additionally, patients receive a JAK inhibitor following transplantation beginning day 5 through 9-12 months after transplant. CONDITIONING: Patients receive melphalan IV over 1 hour on day -5, fludarabine IV over 30-60 minutes on days -5 to -2, and undergo TBI on day -1 or day -1 and day 0. TRANSPLANT: Patients receive peripheral blood stem cell infusion on day 0. GVHD PROPHYLAXIS: Patients then receive cyclophosphamide IV over 3 hours on days 3-4, tacrolimus IV beginning day 5 then PO for about 6 months, mycophenolate mofetil PO BID or TID beginning day 5 for 6 weeks, and G-CSF SC beginning day 7 until neutrophil recovery is \> 1,500/mm\^3. All patients undergo MRI, CT, bone marrow biopsy and aspiration and blood sample collection throughout the trial. Patients also undergo ECHO or MUGA on the trial.

Primary Outcome Measures

Name	Time	Method
Probability of primary and secondary graft failure	Up to 5 years	Primary graft failure is defined as failure to achieve an absolute neutrophil count of \> 500/ul by 42 days after bone marrow or peripheral blood stem cell transplantation. Secondary graft failure is defined as cytopenias after initial engraftment, with (a) donor chimerism of \< 5% or (b) falling donor chimerism with intervention such as second transplant or donor lymphocyte infusion or (c) patient death due to cytopenias, and fall in donor chimerism, even if chimerism is \> 5%. Exclusion criteria for diagnosis of graft failure are (a) disease relapse, (b) graft-versus-host disease, and (c) other causes of cytopenias such as, viral infection and drug toxicity.

Secondary Outcome Measures

Name	Time	Method
Incidence of relapse	At 1 year
Incidence of severe (grade 3 or 4) cytokine release syndrome	Up to 5 years
Non-relapse mortality (NRM)	Day 100
Overall survival	3 years
Incidence of grade II-IV acute graft versus host disease (GVHD)	Up to 5 years
NRM	1 year
Incidence of grade III-IV acute GVHD	Up to 5 years
Incidence of moderate-severe chronic GVHD	Up to 5 years