The study of safety of a new organic arsenic compound in the treatment of hematological malignancies.

Inclusion Criteria

1. Hodgkin's or non-Hodgkin's Lymphoma.

2. ≥ 1 prior therapy and currently requiring therapy.

3. Evaluable disease (defined by disease-specific criteria listed in Appendix 1)

4. ≥ 18 years of age.

5. ECOG performance score ≤ 2 (see Appendix 2).

6. Life-expectancy ≥ 2 months.

7. Written informed consent in compliance with ZIOPHARM policies and the Human Investigation Review Committee with jurisdiction over the site.

8. No anti-cancer therapy exception of hydroxyurea ≤ 3 weeks before Baseline (Day 1, Cycle 1).

9. The following clinical laboratory values < 2 weeks before Baseline:

   • Creatinine ≤ 2X upper limit of normal (ULN).
   • Total bilirubin ≤ 2X ULN.
   • Alanine transaminase (ALT) and aspartate transaminase (AST) ≤ 3X ULN.

Exclusion Criteria

1. New York Heart Association (NYHA) functional class ≥3 myocardial infarction (see Appendix ) within 6 months before Baseline or 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).
2. Pregnant and/or lactating female. (Women of childbearing age must use effective contraception from Screening through the duration of study participation).
3. Uncontrolled infection.
4. Prior seizures ≥ grade-3 in CTC v.3 criteria.
5. Arsenic allergy.
6. Significant neuropathology, defined as grade > 2 per CTCAE Version 3.0.
7. Confusion or dementia.
8. Prior history of neurological deficits (e.g., stroke, dementia, ischemia) that has the potential to confound a post-dose neurological assessment.