ZIO-102 data

Ziopharm Oncology, Inc. announced today the publication of abstracts on its lead product candidate, ZIO-101. The preclinical abstracts are published and available online in Blood, the official journal of the American Society of Hematology. The abstracts include:

• Abstract 5163: "In vitro activity of a novel organic arsenical (S-dimethylarsino-glutathione, ZIO-101) against multiple myeloma," by Lawrence Boise, Ph.D. and coworkers, University of Miami. In this study, the cytotoxic properties and mechanism of action of ZIO-101 were compared to arsenic trioxide (ATO) in four multiple myeloma cell lines. Data suggest that both ZIO-101 and ATO kill myeloma cells but that different modes of action may be involved. Cancer cells resistant to ATO may respond to ZIO-101.
• Abstract 4446: "Comparison of uptake and intracellular induced structural changes of arsenic trioxide, an inorganic compound, and organic arsenic derivative S-dimethylarsino-glutathione (SGLU; ZIO-101) in NB4 acute promyelocytic leukemia (APL) cells," by Taghi Manshouri of University of Texas M.D. Anderson Cancer Center and coworkers. This study showed intracellular accumulation of atomic arsenic is about eight-fold higher for ZIO-101 than for ATO at comparable extracellular arsenic concentrations. The compounds also appear to have different modes of action for inducing programmed cell death: ZIO-101 is more toxic to mitochondria than ATO. The researchers conclude based on these data that the activity of ZIO-101 against cancers might be different than ATO.

ZIO-101 is a novel organic arsenic product candidate currently in Phase I clinical trials. It is the lead product candidate from a "family" of novel organic arsenic compounds licensed to ZIOPHARM Oncology, Inc. from the University of Texas M. D. Anderson Cancer Center and Texas A&M University. A Phase I/II trial and a Phase II trial for ZIO-101 in advanced myeloma are in the advanced planning stage and will likely be followed with exploratory Phase II trials in other cancers. The Company expects a pivotal registration trial to initiate the first half of 2007. A second organic arsenic from the same licensing arrangement, ZIO-102, is the subject of further preclinical studies.

Source: www.ziopharm.com