Ziopharm Oncology, Inc. has signed a definitive agreement to acquire indibulin, a novel synthetic anti-cancer agent that targets mitosis, from affiliates of Baxter Healthcare Corp. Indibulin is available as both an oral and a nanosuspension intravenous (IV) form with the oral form in a Phase I trial and the nanosuspension in late preclinical. Indibulin, now designated as ZIO-301, may offer efficacy, dosing and toxicity advantages as compared to marketed taxanes, including paclitaxel (Taxol), paclitaxel protein-bound particles for injectable suspension (Abraxane), and docetaxel (Taxotere).

The Phase I trial is ongoing at the Netherlands Cancer Institute and University Medical Center, Utrecht. As part of the purchase, the company has acquired the existing drug supply manufactured by Baxter and has assumed all responsibility for the Phase I trial. The company expects to file an IND to initiate a Phase II study with the oral form in the first half of 2007 followed by Phase I trials with the IV formulation.

Taxanes are administered by IV and are among the most effective clinical chemotherapeutic agents with sales of more than $3 billion in 2005. However, all of the marketed agents are associated with severe toxicities. The company believes that indibulin has the potential to provide important advantages over currently marketed taxanes, including reduced toxicity, activity against multi-drug and taxane resistant tumors and the availability of both an oral and an IV nanosuspension.

Terms of the acquisition include an upfront cash payment, clinical and regulatory-based milestone payments, and royalties on net product sales.