Pentostatin and Alemtuzumab as a Preparative Regimen for Allogeneic Peripheral Blood Stem Cell Transplantation

Phase II Related or Unrelated Allogeneic Hematopoietic Cell Transplantation for High-Risk Malignancies, Using a Preparative Regimen of Pentostatin (Nipent®) and Alemtuzumab (Campath®)

This study tests the hypothesis that a purely immunosuppressive preparative regimen allows engraftment of related or unrelated allogeneic hematopoietic stem cells in subjects with high-risk malignancies, without causing the post-transplant myelosuppression (e.g., neutropenia, thrombocytopenia) that occurs with currently used reduced-intensity (nonmyeloablative) preparative regimens. This study incorporates both safety and efficacy endpoints and evaluates a novel preparative regimen of alemtuzumab plus continuous-infusion pentostatin, two immunosuppressive agents with different mechanisms of action, in recipients of related or unrelated allogeneic hematopoietic stem cell transplantation.

Primary Objectives of the study:

• To determine the efficacy of a preparative regimen of pentostatin and alemtuzumab plus related or unrelated allogeneic peripheral blood stem cell transplantation (PBSCT) in inducing durable donor lymphohematopoietic cell chimerism (defined as at least 50% donor cells in the peripheral blood) by 100 days after PBSCT (day +100) in subjects with high-risk malignancies who are at high risk for morbidity and mortality with conventional intensive pre-transplant conditioning regimens.
• To determine the safety of a preparative regimen of pentostatin and alemtuzumab plus related or unrelated allogeneic PBSCT, as measured by the non-relapse mortality at day +100 in the study subject population.

Inclusion Criteria:

One of these diagnoses:

• Acute myeloid leukemia in complete or partial remission
• Acute lymphocytic leukemia in complete or partial remission
• Chronic myeloid leukemia in first or subsequent chronic phase or accelerated phase
• Chronic lymphocytic leukemia that has recurred or failed after at least one course of front-line therapy
• Hodgkin's disease or non-Hodgkin's lymphoma that has failed front-line therapy, is in second or subsequent remission, or is in chemosensitive relapse
• Multiple myeloma that is in complete or partial remission or in chemosensitive relapse
• Myelodysplastic Syndrome classified as intermediate-2 or high risk according to International Prognostic Scoring System
• Metastatic renal cell carcinoma that has failed at least one previous front-line chemotherapy and/or biological therapy regimen and that is radiographically detectable and evaluable
• Treatment with at least one previous course of chemotherapy or biological therapy for the malignancy for which allogeneic PBPCT is being considered (i.e., a subject cannot be enrolled on this study for initial treatment of a malignancy).

AND at least one of the following:

• Age 50 years or older.
• Previous transplant with autologous or allogeneic hematopoietic cells (peripheral blood, bone marrow, or placental blood).
• High-risk status of hematologic malignancy, i.e., not in first complete remission or first chronic phase.
• Presence of other medical condition that could place subject at unacceptably high risk of regimen-related mortality such as documented chronic bronchitis or emphysema; decreased cardiac ejection fraction (but with ejection fraction at least 30%), or history of coronary artery disease; renal insufficiency (but with creatinine clearance at least 30 mL/min); hepatic cirrhosis (but with normal hepatic synthetic function); or documented or presumed invasive fungal infection requiring treatment with intravenous antifungal agent(s).

Exclusion Criteria:

• Eligibility for another clinical therapeutic protocol or standard-of-care treatment that offers higher probability of cure or long-term control of subject's malignancy.
• Progressive Hodgkin's disease, non-Hodgkin's lymphoma, Hodgkin disease or multiple myeloma that is refractory to salvage chemotherapy.
• Acute leukemia (AML or ALL) in relapse, CML in blast phase/blast crisis, or MDS with greater than 30% marrow involvement (MDS-AML). Subjects with these disease characteristics may be considered for this study if complete or partial remissions (CRs or PRs) occur after salvage chemotherapy.
• Severe organ dysfunction, such as: cardiac ejection fraction below 30% or symptomatic ischemic cardiac disease; creatinine clearance below 30 mL/min; carbon monoxide diffusing capacity (DLCO) below 35% and/or need for supplemental oxygen; severe hepatic cirrhosis with ascites and/or varices; hepatic dysfunction associated with abnormal synthetic function (e.g., coagulopathy) and/or bilirubin greater than two times upper limit of normal and/or transaminases (AST or ALT) above four times upper limit of normal.
• Untreated or progressive central nervous system involvement by malignancy
• Subject is pregnant or breast-feeding.
• Karnofsky score below 50
• Seropositivity for human immunodeficiency virus (HIV).
• Life expectancy less than 12 weeks with conventional treatments.
• For subjects who are fertile, refusal to practice contraception upon entering this study and for at least 12 months after PBPCT or after cessation of immunosuppressive treatments (e.g., cyclosporine), whichever occurs later.
• Failure to obtain at least 5.0 x 106 allogeneic donor CD34+ cells per kg of recipient weight in PBPC product.