ZIOPHARM Reports Fourth-Quarter 2016 Financial Results and Provides Update on Recent Activities - Company to Webcast Corporate Update Thursday, February 23, at the 2017 RBC Global Healthcare Conference - BOSTON, MA

ZIOPHARM Reports Fourth-Quarter 2016 Financial Results and Provides Update on Recent Activities

- Company to Webcast Corporate Update Thursday, February 23,

at the 2017 RBC Global Healthcare Conference -

BOSTON, MA February 16, 2017 ZIOPHARM Oncology, Inc. (Nasdaq: ZIOP), a biopharmaceutical company focused on new immunotherapies,

today announced financial results for the fourth quarter ended December 31, 2016, and provided an update on the Company s recent activities.

ZIOPHARM made significant progress over the course of 2016, putting us on track to enter a pivotal study and prosecute multiple high-value studies

across our oncology programs in 2017, focusing on gene therapy, CAR and TCR T-cell therapies, as well as off-the-shelf NK cells, said Laurence Cooper, M.D., Ph.D., Chief Executive Officer of ZIOPHARM. This strategy moves us not just into

a registration pathway with Ad-RTS-hIL-12 + veledimex, but clinically validates the broad potential of our technologies, including our switch systems and the Sleeping Beauty non-viral platform. These advances will be applied across our

program areas, enabling us to increase control, reduce complexity, and manage costs, addressing some of the most significant needs in gene and cell therapy. Ultimately, the ability to deliver controlled, point-of-care therapy makes individualized

treatment targeting each patient s tumor neoantigens possible, a goal with profound clinical implications.

Francois Lebel, M.D., Executive

Vice President, Research and Development, Chief Medical Officer at ZIOPHARM, added: In a recently updated presentation of results from our Phase 1, multi-center study of Ad-RTS-hIL-12 + veledimex in patients with recurrent high-grade gliomas,

we observed a median overall survival of 12.7 months in the 20mg veledimex dose group. This remains a very encouraging outcome compared to historic controls. We look forward to providing an update on our registration pathway in this indication in

the first quarter, and to initiating a pivotal study by the end of 2017.

Ad-RTS-IL-12 + veledimex

Ad-RTS-hIL-12 + veledimex

is a gene therapy candidate for the controlled expression of interleukin 12 (IL-12), a critical protein for stimulating an anti-cancer immune response, using the RheoSwitch Therapeutic System

(RTS ) gene switch. ZIOPHARM is currently conducting a multi-center Phase 1 study of Ad-RTS-hIL-12 + orally-administered veledimex in patients with recurrent or progressive glioblastoma

multiforme (GBM), an aggressive form of brain cancer.

Adoptive Cell Therapies

ZIOPHARM is developing

various immuno-oncology programs, including chimeric antigen receptor (CAR) T cell (CAR-T), T-cell receptor (TCR) T cell (TCR-T), and natural killer (NK) adoptive cell-based therapies. These programs are being advanced in collaboration with Intrexon

Corporation (NYSE: XON), MD Anderson Cancer Center, and Merck Serono, the biopharmaceutical business of Merck KGaA (CAR-T only).

Using the SB system, researchers generated genetically modified T cells that preserved stem-cell memory (TSCM) cells by co-expressing the CAR with mbIL15. Engineered T cells were effective in treating established CD19+ leukemia in mice by facilitating

the long-term persistence of TSCM cells sustained by signaling through recombinant IL15. These findings provide for a translational pipeline of immunotherapies with improved potential by

combining mbIL15 and T cells with diverse specificities.

The Company previously announced the publication of data highlighting the

benefits of using the non-viral SB system to genetically modify T cells to express a CAR for use against CD19-expressing leukemias and lymphomas. The article, titled Phase I trials using Sleeping Beauty to generate CD19-specific CAR T

cells, was published in the Journal of Clinical Investigation (doi:10.1172/JCI86721), and is available online here.

Anticipated 2017 Milestones

2017 RBC Global Healthcare Conference

The Company also announced that Dr. Cooper will present at the 2017 RBC Global Healthcare Conference on Thursday, February 23rd, 2017 at 1:35 p.m. ET. The conference will be held at the Lotte New York Palace in New York City.

access a live audio webcast of the presentation, please visit the Investor Relations section at www.ziopharm.com.

Fourth-Quarter 2016 Financial

ended the quarter with cash and cash equivalents of approximately $81.1 million, which the Company believes will be sufficient to fund its currently planned activities into the fourth quarter of 2017. The cash burn is expected to increase

substantially during 2017 due to the anticipated initiation of a pivotal trial in GBM.

About ZIOPHARM Oncology, Inc.:

ZIOPHARM Oncology is a Boston, Massachusetts-based biotechnology company employing novel gene expression, control and cell technologies to deliver safe,

effective and scalable cell- and viral-based therapies for the treatment of cancer and graft-versus-host-disease. The Company s immuno-oncology programs, in collaboration with Intrexon Corporation (NYSE:XON) and the MD Anderson Cancer Center,

include chimeric antigen receptor T cell (CAR-T) and other adoptive cell-based approaches that use non-viral gene transfer methods for broad scalability. The Company is advancing programs in multiple stages of development together with Intrexon

Corporation s RheoSwitch Therapeutic System technology, a switch to turn on and off, and precisely modulate, gene expression in order to improve therapeutic index. The Company s

pipeline includes a number of cell-based therapeutics in both clinical and preclinical testing which are focused on hematologic and solid tumor malignancies.

Forward-Looking Safe-Harbor Statement:

release contains certain forward-looking information about ZIOPHARM Oncology, Inc. that is intended to be covered by the safe harbor for forward-looking statements provided by the Private Securities Litigation Reform Act of 1995, as

amended. Forward-looking statements are statements that are not historical facts, and in some cases can be identified by terms such as may, will, could, expects, plans,

anticipates, and believes. These statements include, but are not limited to, statements regarding the Company s plans and expectations regarding its securities offerings, fundraising activities and financial strategy,

the progress, timing and results of preclinical and clinical trials involving the Company s drug candidates, and the progress of the Company s research and development programs. All of such statements are subject to certain risks and

uncertainties, many of which are difficult to predict and generally beyond the control of the Company, that could cause actual results to differ materially from those expressed in, or implied by, the forward-looking statements. These risks and

uncertainties include, but are not limited to: our ability to finance our operations and business initiatives and obtain funding for such activities, whether chimeric antigen receptor T cell (CAR T) approaches, Ad-RTS-hIL-12, TCR and NK cell-based

therapies, or any of our other therapeutic candidates will advance further in the pre-clinical or clinical trials process and whether and when, if at all, they will receive final approval from the U.S. Food and Drug Administration or equivalent

foreign regulatory agencies and for which indications; whether chimeric antigen receptor T cell (CAR T) approaches, Ad-RTS-hIL-12, TCR and NK cell-based therapies, and our other therapeutic products will be successfully marketed if approved; the

strength and enforceability of our intellectual property rights; competition from other pharmaceutical and biotechnology companies; and the other risk factors contained in our periodic and interim SEC reports filed from time to time with the

Securities and Exchange Commission, including but not limited to, our Annual Report on Form 10-K for the fiscal year

ended December 31, 2016. Readers are cautioned not to place undue reliance on these forward-looking statements that speak only as of the date hereof, and we do not undertake any obligation

to revise and disseminate forward-looking statements to reflect events or circumstances after the date hereof, or to reflect the occurrence of or non-occurrence of any events.

RheoSwitch Therapeutic System and RTS are registered trademarks of Intrexon Corporation.

Lori Ann Occhiogrosso

ZIOPHARM Oncology, Inc.

ZIOPHARM Oncology, Inc.

Statements of Operations

(in thousands except share and per share data)

ZIOPHARM Oncology, Inc.