Interim study results demonstrate anti-tumor activity of CytRx's INNO-206 in myeloma tumor cells

May 3 2010

CytRx Corporation (NASDAQ:CYTR), a biopharmaceutical company specializing in oncology, today announced interim study results that showed its doxorubicin prodrug INNO-206 demonstrated statistically significant anti-tumor activity in human myeloma tumor cells growing in immune-deficient mice compared to a control group, while exhibiting significantly less toxicity than doxorubicin even though INNO-206 was administered at much higher doses. The study is being conducted by the Institute for Myeloma & Bone Cancer Research under the direction of the Institute's Medical and Scientific Director, noted multiple myeloma authority James R. Berenson, MD. Multiple myeloma is an incurable malignant tumor of the plasma cells in the bone marrow and is the second most common blood-based cancer.

“The results further expand the potential therapeutic value of INNO-206, which has demonstrated anti-tumor activity in multiple cancers. We plan to explore INNO-206 as a viable treatment in numerous oncology indications, including multiple myeloma.”

"Early results from our in vivo multiple myeloma model show marked anti-tumor activity of INNO-206. We have been able to administer greater doses of INNO-206 into animals with improved tolerability compared with doxorubicin," stated Dr. Berenson. "Velcade^® in combination with Doxil^® (pegylated liposomal doxorubicin) has been FDA-approved for multiple myeloma patients who have received one prior therapy, based on the superior outcomes among patients receiving this combination compared to Velcade alone. Based on our study results, the safety profile and efficacy of this new doxorubicin derivative INNO-206, when tested as a single agent in multiple myeloma growing in animals, show that INNO-206 may offer significant benefits over doxorubicin and related drugs when administered in combination with Velcade."

"Dr. Berenson is an internationally known oncologist and expert in multiple myeloma, and he has been directly responsible for multiple breakthrough treatments that improve the length and quality of life of multiple myeloma patients. We are delighted with the interim study results indicating that INNO-206 could have a significant role in the treatment of this incurable disease," said Steven A. Kriegsman, CytRx President and CEO. "The results further expand the potential therapeutic value of INNO-206, which has demonstrated anti-tumor activity in multiple cancers. We plan to explore INNO-206 as a viable treatment in numerous oncology indications, including multiple myeloma."

In the study, 50 mice with implanted multiple myeloma tumors were randomized into five groups of 10 mice: two INNO-206 groups, two doxorubicin groups and a control group. Starting on day seven following tumor implantation, mice received weekly intravenous injections of INNO-206 (10.8 mg/kg or 21.6 mg/kg), doxorubicin (4 mg/kg or 8 mg/kg) or control. Tumor volume is measured weekly. Interim results show that over the course of three injections, mice treated with INNO-206 showed a statistically significant decrease in tumor size compared to mice in the control group. Perhaps most excitingly, substantially fewer deaths occurred in the INNO-206 dose groups as compared with the doxorubicin groups. Only one fatality occurred in the 10.8 mg/kg INNO-206 group, as compared with nine out of ten fatalities in the low-dose doxorubicin group, and ten out of ten fatalities in the high-dose doxorubicin group. The doxorubicin deaths also occurred much earlier than the fatalities in mice administered INNO-206.

CytRx Chief Medical Officer Daniel Levitt, MD, Ph.D., stated, "The Institute for Myeloma & Bone Cancer Research is employing a specifically designed animal model in which human multiple myeloma tumor implants are able to grow and survive in these mice. This model has been shown to retain the chemo-resistant phenotype of the original patient's tumor, which assists in evaluating anti-multiple myeloma activity of novel therapies, making the comparative results between INNO-206 and doxorubicin quite encouraging. Based on these results, we intend to expand the scope of our evaluation of INNO-206 in several of Dr. Berenson's multiple myeloma models."

CytRx holds the exclusive worldwide rights to INNO-206. The Company has previously announced plans to initiate Phase 2 proof-of-concept clinical trials in patients with pancreatic cancer, gastric cancer and soft tissue sarcomas, upon the completion of optimizing the formulation of INNO-206. Based on the multiple myeloma interim results, the Company is exploring the possibility of rapidly including multiple myeloma in its INNO-206 clinical development plans.