BOSTON, May 15, 2013 (GLOBE NEWSWIRE) -- ZIOPHARM Oncology, Inc. (Nasdaq:ZIOP) today announced that Gerald P. Linette, MD, PhD, of the Washington University School of Medicine, will present updated clinical results from a Phase 1 study of Ad-RTS-hIL-12, a novel DNA-based therapeutic candidate in advanced melanoma at the 2013 American Society for Clinical Oncology (ASCO) Annual Meeting being held May 31 – June 4, 2013 at McCormick Place in Chicago, IL. Results will be presented during the Developmental Therapeutics – Immunotherapy Poster Discussion Session on Saturday, June 1 st from 1:15 pm – 5:15 pm CT in a poster titled: "A phase I open-label study of Αd-RTS-hIL-12, an adenoviral vector engineered to express hIL-12 under the control of an oral activator ligand, in subjects with unresectable stage III/IV melanoma." (Poster Board #14, Room #S405). Immediately following, the poster will be included in the discussion session beginning at 5:15pm CT in Room #S406. The study abstract (#3022) released today can be accessed at www.ASCO.org . About ZIOPHARM Oncology, Inc.: ZIOPHARM Oncology is a biopharmaceutical company focused on the development and commercialization of new cancer therapies. The Company's clinical programs include: 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. Ad-RTS-IL-12 uses synthetic biology to enable controlled delivery of therapeutic interleukin-12 (IL-12), a protein important for enhancing the development of an immune response to cancer. In partnership with Intrexon Corporation, ZIOPHARM's DNA synthetic biology platform employs an inducible gene-delivery system that enables controlled delivery of genes that produce therapeutic proteins to treat cancer. This controlled delivery is achieved by producing IL-12 under the control of Intrexon's proprietary biological "switch" (the RheoSwitch Therapeutic System® or RTS® platform) to turn on/off the therapeutic protein expression at the tumor site.