ZIOPHARM submits IND with FDA for Ad-RTS-IL-12 Phase I study in cancer

ZIOPHARM Oncology, Inc. (Nasdaq: ZIOP), a drug development company employing small molecule and synthetic biology approaches to cancer therapy, today announced that it has submitted an Investigational New Drug (IND) application to the U.S. Food & Drug Administration (FDA) to begin clinical study of Ad-RTS-IL-12 (INXN 2001/1001), a novel DNA-based therapeutic candidate. When initiated, the Phase I study will evaluate safety in addition to immunological and biological effects of the therapeutic candidate in patients with melanoma. Ad-RTS-IL12 is the second clinical oncology product candidate from the ZIOPHARM/Intrexon Corporation's exclusive, synthetic biology channel partnership.

Through intratumoral injection, Ad-RTS-IL-12 employs an adenoviral vector (Ad) to deliver directly into the patient's own cells a gene which expresses Interleukin-12 (IL-12), a potent anticancer cytokine. Production of IL-12 within the cell is in turn tightly regulated by the Intrexon RheoSwitch Therapeutic System™ (RTS^TM), a "gene switch" controlled by an activator ligand taken orally. IL-12 is a naturally occurring regulatory cytokine that has a function central to the initiation and regulation of cellular immune responses.

"Cancer is a disease of DNA and synthetic biology uses genetic tools to offer us entirely new approaches to addressing its challenges," said Mark Thornton, M.D., Ph.D., Executive Vice President and Chief Development Officer of ZIOPHARM. "IL-12, for example, naturally elicits an immune response to cancer, but is too toxic to be given as a recombinant protein. By producing IL-12 in the body with a DNA-based drug, and using our unique technology to switch this production on or off with a pill, we expect to achieve therapeutic levels of IL-12 without being limited by the toxicities typically associated with recombinant therapy. Both Ad-RTS-IL-12 and DC-RTS-IL-12 (INXN 3001/1001), our clinical-stage candidate that employs the patient's transduced dendritic cells to deliver Ad-RTS-IL-12, represent truly novel and pioneering treatment."

Data from two preclinical studies of Ad-RTS-IL-12 in various in vivo cancer models will be presented at the 2011 Annual Meeting of the American Society of Gene and Cell Therapy (ASGCT), being held May 18-21 in Seattle, Washington. Data from a Phase Ib trial with DC-RTS-IL-12 will be presented at the 2011 Annual Meeting of the American Society of Clinical Oncology (ASCO) being held June 3-7 in Chicago, Illinois.