Ziopharm rises on preclinical cancer therapy study

NEW YORK (AP) -- Shares of Ziopharm Oncology Inc. rose Tuesday after the company reported encouraging results from a preclinical trial of a cancer therapy.

The drug, designated Ad-RTS-mIL-12, is designed to enable the controlled delivery of a protein important for immune response to cancer. Ziopharm said larger doses of the drug were linked to bigger decreases in the growth rate of the tumors, and that side effects appeared to be minimal. The drug was tested on mice and the study was designed to evaluate the effects of the drug on breast cancer.

Ziopharm and Intrexon Corp. are conducting two mid-stage human trials of the drug. One is designed to study the drug's effectiveness against melanoma, and the other involves a combination of Ad-RTS-mIL-12 and palifosfamide, another experimental Ziopharm drug, as a treatment for breast cancer.

Ziopharm shares gained 22 cents, or 13.6 percent, to $1.84 in midday trading.

Ziopharm doesn't have any approved products, and palifosfamide is its most advanced experimental drug. On March 26 the company said palifosfamide failed in a late-stage study that evaluated the drug as a treatment for soft tissue sarcoma, a cancer that forms in connective tissue. Ziopharm said it would immediately switch its strategic focus to synthetic biology programs and start a restructuring program to muster resources for that.

Shares of Ziopharm have lost 68.4 percent of their value since then.