Trial Outcomes & Findings for Clofarabine and Low-Dose Total-Body Irradiation in Treating Patients With Acute Myeloid Leukemia Undergoing Donor Peripheral Blood Stem Cell Transplant (NCT NCT01252667)

Last Updated: 2020-04-16

Results Overview

The primary objective of part 1 is to determined the highest dose of clofarabine that can be tolerated safely in conjunction with nonmyeloablative transplant. If three patients successfully transplant without DLT, dose escalation occurs. If one of those three patients experiences DLT an additional three patients will be treated using the same dose. If a second DLT is observed in the first 3-6 patients, or if three patients are successfully transplanted without DLT at the highest dose the study will proceed to Part 2 using the maximum tolerated dose. A Clofarabine related dose-limiting toxicity is defined as a grade 4 toxicity involving the lungs, heart, liver (not resolving in 48 hours), kidneys (not resolving in 48 hours), gastrointestinal tract, and/or central nervous system.

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

44 participants

Primary outcome timeframe

14 days post-transplant

Results posted on

2020-04-16

Participant Flow

Participant milestones

Participant milestones
Measure	Part 1 - Dose 1 (30 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 2 (40 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 3 (50 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 3 (50 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI
Overall Study STARTED	3	3	3	35
Overall Study COMPLETED	3	3	3	34
Overall Study NOT COMPLETED	0	0	0	1

Reasons for withdrawal

Reasons for withdrawal
Measure	Part 1 - Dose 1 (30 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 2 (40 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 3 (50 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 1 (30 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 2 (40 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 3 (50 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI
Overall Study Transplant aborted post-conditioning	0	0	0	0	0	1

Baseline Characteristics

Clofarabine and Low-Dose Total-Body Irradiation in Treating Patients With Acute Myeloid Leukemia Undergoing Donor Peripheral Blood Stem Cell Transplant

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Part 1 - Dose 1 (30 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 2 (40 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 3 (50 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 1 (30 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 2 (40 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 3 (50 mg/m^2 Clofarabine) n=35 Participants CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Total n=44 Participants Total of all reporting groups
Age, Categorical <=18 years	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	—	—	0 Participants n=8 Participants	0 Participants n=8 Participants
Age, Categorical Between 18 and 65 years	0 Participants n=5 Participants	2 Participants n=7 Participants	1 Participants n=5 Participants	—	—	8 Participants n=8 Participants	11 Participants n=8 Participants
Age, Categorical >=65 years	3 Participants n=5 Participants	1 Participants n=7 Participants	2 Participants n=5 Participants	—	—	27 Participants n=8 Participants	33 Participants n=8 Participants
Age, Continuous	73.4 years n=5 Participants	64.1 years n=7 Participants	67.7 years n=5 Participants	—	—	69.5 years n=8 Participants	69.1 years n=8 Participants
Sex: Female, Male Female	1 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants	—	—	13 Participants n=8 Participants	16 Participants n=8 Participants
Sex: Female, Male Male	2 Participants n=5 Participants	2 Participants n=7 Participants	2 Participants n=5 Participants	—	—	22 Participants n=8 Participants	28 Participants n=8 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	—	—	2 Participants n=8 Participants	2 Participants n=8 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	3 Participants n=5 Participants	3 Participants n=7 Participants	3 Participants n=5 Participants	—	—	31 Participants n=8 Participants	40 Participants n=8 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	—	—	2 Participants n=8 Participants	2 Participants n=8 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	—	—	0 Participants n=8 Participants	0 Participants n=8 Participants
Race (NIH/OMB) Asian	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	—	—	1 Participants n=8 Participants	1 Participants n=8 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	—	—	0 Participants n=8 Participants	0 Participants n=8 Participants
Race (NIH/OMB) Black or African American	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	—	—	0 Participants n=8 Participants	0 Participants n=8 Participants
Race (NIH/OMB) White	3 Participants n=5 Participants	3 Participants n=7 Participants	3 Participants n=5 Participants	—	—	32 Participants n=8 Participants	41 Participants n=8 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	—	—	0 Participants n=8 Participants	0 Participants n=8 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	—	—	2 Participants n=8 Participants	2 Participants n=8 Participants
Region of Enrollment United States	3 participants n=5 Participants	3 participants n=7 Participants	3 participants n=5 Participants	—	—	35 participants n=8 Participants	44 participants n=8 Participants

PRIMARY outcome

Timeframe: 14 days post-transplant

Population: Analysis only applies to subjects accrued in Part 1 of the study.

Outcome measures

Outcome measures
Measure	Part 1 - Dose 1 (30 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 2 (40 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 3 (50 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 1 (30 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 2 (40 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 3 (50 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI
Part 1: Number of Participants With Dose Limiting Toxicities (DLT)	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants

PRIMARY outcome

Timeframe: 6 months post-transplant

Population: Analysis only applies to subjects accrued in Part 2 of the study. Two subjects in Low Risk status and not evaluable toward this outcome. One subject aborted transplant during conditioning and subsequently expired. This subject was counted towards accrual but not evaluated with respect to outcome measures.

Number of high risk patients with relapsed disease after receiving the maximum dose of clofarabine. Relapse is defined as the presence of \>5% aberrant blasts by morphology on a marrow aspirate or the presence of circulating blasts in the peripheral blood.

Outcome measures

Outcome measures
Measure	Part 1 - Dose 1 (30 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 2 (40 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 3 (50 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 1 (30 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 2 (40 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 3 (50 mg/m^2 Clofarabine) n=32 Participants CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI
Part 2: Number of Participants With Relapsed Disease	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	3 Participants

SECONDARY outcome

Timeframe: 1 Year post-transplant

Population: No subjects were treated with Dose 1 or 2 in Part 2 as no DLTs were observed in Part 1.

Number of patients surviving without progressive disease post-transplant. Progression is defined as the presence of \>5% aberrant blasts by morphology on a marrow aspirate or the presence of circulating blasts in the peripheral blood.

Outcome measures

Outcome measures
Measure	Part 1 - Dose 1 (30 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 2 (40 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 3 (50 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 1 (30 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 2 (40 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 3 (50 mg/m^2 Clofarabine) n=35 Participants CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI
Number of Participants Surviving Progression-free.	0 Participants	2 Participants	1 Participants	0 Participants	0 Participants	21 Participants

SECONDARY outcome

Timeframe: 1 Year post-transplant

Population: No subjects were treated with Dose 1 or 2 in Part 2 as no DLTs were observed in Part 1.

Number of patients surviving overall post-transplant.

Outcome measures

Outcome measures
Measure	Part 1 - Dose 1 (30 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 2 (40 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 3 (50 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 1 (30 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 2 (40 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 3 (50 mg/m^2 Clofarabine) n=35 Participants CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI
Number of Participants Surviving Overall	0 Participants	2 Participants	1 Participants	0 Participants	0 Participants	22 Participants

SECONDARY outcome

Timeframe: 100 days post-transplant

Population: No subjects were treated with Dose 1 or 2 in Part 2 as no DLTs were observed in Part 1.

Number of patients who expired without disease progression/relapse.

Outcome measures

Outcome measures
Measure	Part 1 - Dose 1 (30 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 2 (40 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 3 (50 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 1 (30 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 2 (40 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 3 (50 mg/m^2 Clofarabine) n=35 Participants CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI
Number of Non-Relapse Mortalities (NRM)	0 Participants	1 Participants	0 Participants	0 Participants	0 Participants	1 Participants

SECONDARY outcome

Timeframe: 1 Year post-transplant.

Population: No subjects were treated with Dose 1 or 2 in Part 2 as no DLTs were observed in Part 1. One subject on Part 2 Dose 3 aborted transplant during conditioning and subsequently expired. This subject was counted towards accrual but not evaluated with respect to outcome measures.

Number of patients who graft rejected post-transplant. Graft rejection is defined as \<5% donor peripheral blood T cells (CD3+).

Outcome measures

Outcome measures
Measure	Part 1 - Dose 1 (30 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 2 (40 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 3 (50 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 1 (30 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 2 (40 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 3 (50 mg/m^2 Clofarabine) n=34 Participants CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI
Number of Participants Who Graft Rejected.	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants	0 Participants

SECONDARY outcome

Timeframe: 1 Year post-transplant

Population: The studies have not been carried out on the specimens to evaluate this outcome measure.

Potential prognostic markers will be assessed by polymerase chain reaction (PCR) to determine their prognostic value.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: 1 Year post-transplant

Number of patients with MRD post-transplant, detected in the bone marrow as cytogenetic abnormalities or \<5% monoclonal blasts by flow cytometry.

Outcome measures

Outcome measures
Measure	Part 1 - Dose 1 (30 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 2 (40 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 1 - Dose 3 (50 mg/m^2 Clofarabine) n=3 Participants CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 1 (30 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 30 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 2 (40 mg/m^2 Clofarabine) CONDITIONING REGIMEN: Patients receive 40 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI	Part 2 - Dose 3 (50 mg/m^2 Clofarabine) n=35 Participants CONDITIONING REGIMEN: Patients receive 50 mg/m\^2 clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI on day 0. IMMUNOSUPPRESSION: Patients with related donors receive cyclosporine PO every 12 hours on days -3 to 56 with taper to day 180 and mycophenolate mofetil PO every 12 hours on days 0 to 28. Patients with unrelated donors receive cyclosporine PO every 12 hours on days -3 to 100 with taper to day 180 and mycophenolate mofetil PO every 8 hours on days 0 to 40 with taper to day 96. TRANSPLANTATION: Patients undergo allogeneic PBSCT on day 0. Allogeneic Hematopoietic Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Clofarabine: Given IV Cyclosporine: Given PO Laboratory Biomarker Analysis: Correlative studies Mycophenolate Mofetil: Given PO Peripheral Blood Stem Cell Transplantation: Undergo allogeneic hematopoietic PBSCT Pharmacological Study: Optional correlative studies Total-Body Irradiation: Undergo TBI
Number of Participants With Minimal Residual/Recurring Disease (MRD) Post-transplant	0 Participants	2 Participants	0 Participants	0 Participants	0 Participants	6 Participants

SECONDARY outcome

Timeframe: Blood was drawn on day -6 before the first clofarabine dosing, at the end of the infusion, and at 3, 4, 5, 6 and 24 hours after the start of infusion. Only pre-dose samples were drawn on days -5, -4, and -3.

Population: Pharmacokinetic analyses were performed on only a subset of patients.

Pharmacokinetic measurement of the volume of plasma from which clofarabine is completely removed per unit time. Clearance normalized to actual body weight. Pharmacokinetic analyses were performed on only a subset of patients and no aggregate calculations were made using the data.