Restructuring to Place Exclusive Strategic Focus on Synthetic Biology Programs Company to Host Conference Call Today, March 26, 2013 at 8:30 AM ET NEW YORK, March 26, 2013 (GLOBE NEWSWIRE) -- ZIOPHARM Oncology, Inc. (Nasdaq:ZIOP), a biopharmaceutical company focused on the development and commercialization of new cancer therapies, announced today that its Phase 3 trial of palifosfamide (ZIO-201) for the treatment of metastatic soft tissue sarcoma in the first-line setting (PICASSO 3) did not meet its primary endpoint of progression-free survival (PFS). The study's independent data monitoring committee (IDMC) has recommended that patients be followed for overall survival (OS), the study's secondary endpoint, however the Company does not expect to continue follow up for OS. Palifosfamide was well tolerated, with a safety profile in combination with doxorubicin observed in the study comparable with other palifosfamide clinical trials in soft tissue sarcoma. Full data from PICASSO 3 will be submitted for publication in a scientific journal. With this outcome, ZIOPHARM has made the decision to immediately place exclusive strategic focus on its synthetic biology programs, which are being developed in partnership with Intrexon Corporation. The lead therapeutic candidate in this program is Ad-RTS IL-12, a DNA therapeutic to enable controlled delivery of therapeutic interleukin-12 (IL-12), a protein important for an immune response to cancer. This is achieved by placing IL-12 under the control of Intrexon's proprietary biological "switch" (the RheoSwitch Therapeutic System ®, RTS ®) to turn on/off the therapeutic protein expression. Ad-RTS IL-12 is currently being tested in two Phase 2 studies, the first for the treatment of advanced melanoma, and the second in combination with palifosfamide for the treatment of non-resectable recurrent or metastatic breast cancer. A highly focused team within the Company will be deployed in support of these programs. As a result, a restructuring plan is immediately being put into place to align staffing to current objectives and to marshal its resources toward achieving success with its synthetic biology programs.