Inclusion Criteria:

- Histologically confirmed relapsed or refractory NHL that includes: follicular
lymphoma of any grade; marginal zone lymphoma; small lymphocytic lymphoma/chronic
lymphocytic leukemia; mantle cell lymphoma; lymphoplasmacytic lymphoma; low-grade
B-cell lymphoma not otherwise specified; diffuse large B-cell lymphoma, anaplastic
large cell lymphoma, peripheral T-cell lymphoma, angioimmunoblastic T-cell lymphoma.

- One or more prior line of chemotherapy, immunotherapy, or radioimmunotherapy.

- Measurable disease on cross sectional imaging of at least 2cm.

- ECOG Performance Status 0-2

- 18 years of age or older

- Life expectancy of greater than 3 months

- Normal organ and marrow function as outlined in the protocol

- Must agree to use adequate contraception prior to study entry and for the duration of
study participation

Exclusion Criteria:

- Patients who have had chemotherapy, rituximab, or radiotherapy within 4 weeks, or
radioimmunotherapy within 8 weeks prior to entering the study

- Receiving any other investigational agent

- Known brain metastases

- History of allergic reactions attributed to compounds of similar chemical or biologic
composition to Clofarabine

- Systemic fungal, bacterial, viral, or other infection not controlled

- Pregnant or lactating

- Prior history of another malignancy (except for non-melanoma skin cancer or in situ
cervical or breast cancer) unless disease free for over one year

- Uncontrolled intercurrent illness including, but not limited to ongoing or active
infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac
arrhythmia, or psychiatric illness/social situations that would limit compliance with
study requirements

- Prior allogeneic stem cell transplantation