ZIOPHARM Presents at European Society of Hematology Meeting; Updates ZIO-101 Clinical Development Strategy.

MADEIRA, Portugal -- ZIOPHARM Oncology, Inc. (OTC BB: ZIOP) presented phase I data on its product candidate, ZIO-101, a novel organic arsenic, at the Second European Society of Hematology Conference on Myeloproliferative Disorders in Madeira, Portugal. Results from this ongoing phase I study continue to support accelerated development of ZIO-101 in diverse cancers.

The presentation, "ZIO-101: A novel organic arsenic active in acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS); Possible role in myeloproliferative disorders (MPD)", addressed safety and activity in patients with advanced AML and MDS. An anti-leukemia effect was seen in three extensively pre-treated patients; a fourth with prior MDS stopped needing frequent red blood cell (RBC) transfusions and had a marked functional improvement. The trial continues enrolling subjects with diverse leukemias, lymphomas and other blood and bone marrow disorders.

ZIOPHARM believes data from ongoing phase I studies of ZIO-101 show activity in other hematologic cancers and solid tumors. ZIO-101 can be safely given at significantly higher doses than inorganic arsenics, like arsenic trioxide (Trisenox(R)). Based on these encouraging data, ZIOPHARM anticipates expanding its phase II development program for ZIO-101 to include not only multiple myeloma but other hematologic cancers and solid tumors. The Company also expects to develop an oral form of ZIO-101.

ZIO-101 is a small molecule licensed from The University of Texas M. D. Anderson Cancer Center and Texas A&M University. ZIO-101 phase I studies continue in both solid tumor and blood cancers. Phase I/II and phase II studies, including the exploration of alternative dosage regimens, have been or will be initiated in patients with advanced myeloma. The Company expects to begin phase II studies in other blood and bone marrow cancers and solid tumors and to advance an oral form in to clinical evaluation in the future. ZIOPHARM anticipates availability of additional data from the ongoing phase I and phase I/II studies at upcoming medical meetings.

About ZIOPHARM Oncology, Inc.

ZIOPHARM Oncology, Inc. is a biopharmaceutical company engaged in the development and commercialization of a diverse, risk-sensitive portfolio of in-licensed cancer drugs to address unmet medical needs. The Company applies new insights from molecular and cancer biology to understand the efficacy and safety limitations of approved and developmental cancer therapies and identifies proprietary and related molecules for better patient treatment. For more information, visit www.ziopharm.com.

Forward-Looking Safe Harbor Statement:

This press release contains forward-looking statements for ZIOPHARM Oncology, Inc. that involve risks and uncertainties that could cause the Company's actual results to differ materially from the anticipated results and expectations expressed in these forward-looking statements. These statements are based on current expectations, forecasts and assumptions that are subject to risks and uncertainties, which could cause actual outcomes and results to differ materially from these statements. Among other things, there can be no assurance that any of the Company's development efforts relating to its product candidates will be successful, or such product candidates will be successfully commercialized. Other risks that affect forward-looking information contained in this press release include the possibility of being unable to obtain regulatory approval of the Company's product candidates, the risk that the results of clinical trials may not support the Company's claims, and risks related to the Company's ability to protect its intellectual property and its reliance on third parties to develop its product candidates. The Company assumes no obligation to update these forward-looking statements, except as required by law.