Inclusion Criteria

Inclusion Criteria

1. Patients with non-Hodgkin's Lymphomas that are refractory to standard therapies for
their condition.(As of protocol amendment 6.0 dated 8/26/2009)

2. Men and women of ≥ 18 years of age.

3. ECOG performance score ≤ 2 (see Appendix 4).

4. Eligible subjects with lymphomas must have measurable disease as defined by the
revised International Working Group response criteria (Appendix 7)

5. Life expectancy ≥ 12 weeks.

6. Adequate bone marrow, liver and renal function as assessed by the following
laboratory requirements, to be conducted <2 weeks prior to Baseline:

- Creatinine ≤ 2X upper limit of normal (ULN) OR a calculated creatinine clearance
≥ 50 cc/min

- Total bilirubin ≤ 2X ULN

- Alanine transaminase (ALT) and aspartate transaminase (AST) ≤ 3X ULN

- Granulocytes in peripheral blood ≥1 x 109/L, hemoglobin ≥8.5 g/dL, and platelets
≥50,000 /µL

7. Written informed consent in compliance with ZIOPHARM policies and the Human
Investigation Review Committee (IEC/IRB) having jurisdiction over the site.

Exclusion Criteria

1. New York Heart Association (NYHA) functional class ≥3 myocardial infarction (see
Appendix 5) within 6 months.

2. Uncontrolled cardiac arrhythmia other than asymptomatic atrial fibrillation; a QTc
≥450 msec; or a ≥Grade 2 atrioventricular (AV) block or left bundle branch block
(LBBB); or documented history of prolonged QTc.

3. Pregnant and/or lactating female. (Women of childbearing age must use effective
contraception from Screening through the duration of Study participation.)

4. Uncontrolled systemic infection (documented with microbiological studies).

5. Metastatic brain or meningeal tumors.

6. Patients with seizure disorder requiring medication (such as anti-epileptics).

7. History of confusion or dementia or neurological condition that could mask a
potential adverse response to Study Drug which may include transient ischemic attack,
Parkinson's disease, thrombotic or hemorrhagic stroke, Alzheimers, and other
neurological disorders.

8. Anticancer chemotherapy or immunotherapy during the study or within 4 weeks of Study
entry (mitomycin C or nitrosureas should not be given within 6 weeks of Study entry).

9. Radiotherapy during study or within 3 weeks of Study entry.

10. Surgery within 4 weeks of start of Study Drug.

11. Investigational drug therapy outside of this trial during or within 4 weeks of Study
entry.

12. History of invasive second primary malignancy diagnosed within the previous 3 years
except for Stage I endometrial/cervical carcinoma or prostate carcinoma treated
surgically, and non-melanoma skin cancer.

13. Substance abuse, medical, psychological or social conditions that may interfere with
the patient's participation in the study or evaluation of Study results.

14. Any condition that is unstable or could jeopardize the safety of the patient and
his/her compliance in the Study.

15. Arsenic allergy.