Bendamustine With or Without Cyclophosphamide in Preventing GVHD in Patients Undergoing Stem Cell Transplant

PRIMARY OBJECTIVE:

I. Evaluate the safety of substituting the standard post-transplant cyclophosphamide (PT-CY) given on day +3 and +4 with post-transplant bendamustine (PT-BEN) in patients undergoing HLA-mismatched hematopoietic cell transplantation.

SECONDARY OBJECTIVES:

I. To evaluate treatment-related mortality. II. To assess acute and chronic graft-versus-host disease (GVHD). III. To assess overall survival, progression-free survival and relapse rates. IV. To evaluate the risk of acute cystitis. V. To evaluate immune reconstitution after transplantation.

OUTLINE: This is a dose-escalation study of bendamustine. Patients are assigned to 1 of 2 treatment schedules.

SCHEDULE I (NON-LYMPHOMA): Patients receive fludarabine intravenously (IV) over 1 hour on days -5 to -2, melphalan IV over 30 minutes on days -5 and -4, and undergo total body irradiation (TBI) on day -1 and stem cell transplantation IV over 2-6 hours on day 0. Depending on when the trial was joined, patients receive cyclophosphamide IV over 3 hours or bendamustine IV over 30-60 minutes or cyclophosphamide IV over 3 hours and bendamustine IV over 30-60 minutes on day 3. Patients also receive bendamustine IV over 30-60 minutes on day 4. Beginning day 5, patients receive tacrolimus IV followed by orally (PO) once daily (QD) or twice daily (BID) for 6 months and mycophenolate mofetil PO thrice daily (TID) until day 100. Beginning day 7, patients receive filgrastim-sndz subcutaneously (SC) QD until blood cell levels return to normal.

SCHEDULE II (LYMPHOID MALIGNANCIES): Patients receive fludarabine IV over 1 hour, bendamustine IV over 30-60 minutes on days -5 to -3 and undergo TBI on day -1 and stem cell transplantation over 2-6 hours on day 0. Depending on when the trial was joined, patients receive cyclophosphamide IV over 3 hours or bendamustine IV over 30-60 minutes or cyclophosphamide IV over 3 hours and bendamustine IV over 30-60 minutes on day 3. Patients also receive bendamustine IV over 30-60 minutes on day 4. Beginning day 5, patients receive tacrolimus IV followed by PO QD or BID for 6 months and mycophenolate mofetil PO TID until day 100. Beginning day 7, patients receive filgrastim-sndz SC QD until blood cell levels return to normal. CD20+ patients receive rituximab IV over 4-6 hours on days -13, -6, 1, and 8.

After completion of study treatment, patients are followed weekly for 3 months, every 3 months in year 1, and every 6 months in year 2.

Inclusion criteria

• Patient with hematologic malignancies.
• Donor: Matched sibling, matched unrelated, mismatched or haploidentical
• Zubrod performance 0 to 2 or Karnofsky of at least 60.
• Adequate organ function at time of study entry:

• Creatinine less than or equal to 1.6 mg/dL and creatinine clearance >/= 30 ml/min. Creatinine clearance will be calculated using the Cockcroft-Gault equation
• Total bilirubin less than < 1.5 x UNL
• SGPT < 2.5 x ULN
• Ejection fraction >/= 40%
• FEV1, FVC and DLCO >/= 40%
• Female patients of childbearing potential must agree to use an effective method of birth control while on study and for 6 months after the last dose of bendamustine. Male patients with female partners of childbearing potential must agree to use an effective method of birth control while on study and for 3 months after the last dose of bendamustine.

Exclusion criteria

• Pregnant or nursing women.
• Known to be HIV positive
• Active and uncontrolled disease/infection
• Unable or unwilling to sign consent
• Current active hepatic or biliary disease (with exception of Gilbert's syndrome)
• Active hepatitis B or C.
• Toxicities (grade > 1) unresolved from prior treatment (including chemotherapy, targeted therapy, immunotherapy, experimental agents radiation, or surgery.
• Patients with standard risk acute leukemia in first complete remission and patients with chronic myeloid leukemia in first chronic will be excluded during escalated phase.