Phase 2 Trial of Prophylactic Rituximab Therapy for Prevention of CGVHD

To test if prophylactic anti-B-cell therapy (weekly rituximab) given within 60 to 90 days
after allogeneic transplantation will decrease allogeneic donor B-cell immunity and possibly
the incidence of chronic graft-vs-host disease (cGvHD).

Recipient Inclusion Criteria:

- Between 18 and 76 years of age

- Chronic lymphocytic leukemia (CLL):

- Unmutated IgG VH gene status

- Mutated IgG VH genes (> 2% nucleotide change compared to somatic sequence)

- Complete remission benefit most from allogeneic hematopoietic stem cell
transplant (HSCT).

(Physicians will be encouraged to provide aggressive chemotherapy prior to nonmyeloablative
transplantation.)

- Mantle cell lymphoma (MCL): Transplant physicians believe subject would benefit from
allogeneic HSCT.

- Adequate renal (Cr < 2.4 mg/dL) and hepatic (Bilirubin < 3.0 mg/dL, Aspartate
aminotransferase (AST) < 100 IU) function.

- Men and women of reproductive potential must agree to use an acceptable method of
birth control during treatment and for six months after completion of treatment.

- All subjects must provide written informed consent

Donor Inclusion Criteria:

- Genotypically or phenotypically human leukocyte antigen (HLA)-identical.

- Age < 76 unless cleared by institutional PI

- Capable of giving written, informed consent.

- Must consent to peripheral blood stem cell (PBSC) mobilization with G-CSF and
apheresis

Recipient Exclusion Criteria:

- Recipient has a 9 of 10 or 10 of 10 HLA identical donor (high resolution molecular
genotyping at HLA A, B, C and DrB1, and DQ)

- Pregnancy

- Lactating

- Serious uncontrolled infection

- HIV seropositivity

- Hepatitis B or C seropositivity

- Cardiac function: ejection fraction < 40% or uncontrolled cardiac failure

- Pulmonary: Diffusing capacity - carbon monoxide (DLCO) < 50% predicted

- Liver function abnormalities: elevation of bilirubin to ≥ 3 mg/dL and/or AST > 100

- Renal: creatinine > 2.4

- Karnofsky performance score ≤ 60%

- Patients with poorly controlled hypertension (systolic blood pressure > 150 or
diastolic blood pressure > 90 repeatedly).

- Known life-threatening hypersensitivity to rituximab or other anti-B cell antibodies.

- Inability to comply with the allogeneic transplant treatment.

- Uncontrolled central nervous system (CNS) involvement with disease

Donor Exclusion Criteria:

- Identical twin to subject

- Contra-indication to subcutaneous G-CSF at a dose of 16 mg/kg/d for 5 consecutive days

- Serious medical or psychological illness

- Prior malignancy within the preceding five years, with the exception of non-melanoma
skin cancers.

- HIV seropositivity