December 1, 2004

CytRx Announces Scientific Data Showing the Potential of Its Oral Drug, Iroxanadine, for the Treatment of Cardiovascular Disease

LOS ANGELES, Dec. 1 /PRNewswire-FirstCall/ -- CytRx Corporation announced that its orally available drug candidate, iroxanadine, was effective in treating cardiovascular disease in an experimental mouse model for atherosclerosis. The experiments demonstrated that iroxanadine significantly reduced plaque formation and arterial thickening in mice, both of which are symptoms that lead to serious cardiovascular disease. According to the National Heart, Lung & Blood Institute, atherosclerosis is a leading cause of illness and death in the U.S. and affects approximately 4.6 million people annually.

The experiments were performed in a strain of mouse ("ApoE") which is genetically engineered to have deficient cholesterol metabolism, which results in acceleration of the generation of cardiovascular disease. Iroxanadine significantly reduced the progression of cardiovascular disease in these animals. "This strain of mouse rapidly develops the classic hallmarks of atherosclerosis, including the formation of plaque and a thickening of blood vessel walls," said Louis Ignarro, Ph.D., Nobel Laureate and world acclaimed expert in the field of cardiovascular disease. "Treatment with iroxanadine significantly decreased plaque formation and reduced arterial thickening. This is consistent with its proposed mechanism of action, namely restoring the normal function of the endothelial cells lining the blood vessels," said Dr. Ignarro.

Iroxanadine is believed to work through the activation of certain "molecular chaperone" proteins that repair normal damage to each cell. "The utility of chaperone proteins in preventing the damage that leads to cardiovascular disease has been appreciated in the scientific literature for some time," said Jack Barber, Ph.D., Sr. Vice President, Drug Development. "However, until now we were not aware of an easy way to stimulate the right chaperones in the right tissues. These unpublished preclinical results, in conjunction with the human safety data previously generated from a Phase II clinical trial, suggest that iroxanadine may be the right way," said Dr. Barber.

"We continue to be impressed by the therapeutic potential of the three oral drug candidates we recently acquired from Biorex," said Steven Kriegsman, President and CEO. "The main motivation for our acquisition was the drug arimoclomol, for which we plan to initiate a phase II clinical trial for ALS ('Lou Gehrig's disease') in the second quarter of 2005 and also continue development for type 2 diabetes. CytRx's internal drug development efforts will continue to focus on the utility of iroxanadine for other diseases, such as diabetic wound healing and retinopathy, but we are actively seeking to partner with a large pharmaceutical company for the more challenging, but more lucrative, cardiovascular indication," said Mr. Kriegsman.

CytRx's recent acquisition of the clinical and pharmaceutical assets and related intellectual property of Biorex Research & Development Company significantly expanded and accelerated the company's drug development pipeline with the addition of three oral, clinical stage drug candidates, a library of 500 small molecule drug candidates, and an extended patent portfolio. The acquisition positions CytRx as a clinical-stage company and also complements the company's business by expanding the scope of therapeutic development programs.

About CytRx Corporation

CytRx Corporation is a biopharmaceutical research and development company, based in Los Angeles with a subsidiary in Worcester, Massachusetts. The company is engaged in the development of products, primarily in the area of small molecules and ribonucleic acid interference (RNAi), in a variety of therapeutic categories. The company recently acquired 3 clinical stage compounds and a library of 500 small molecule drug candidates from Biorex Research & Development Company. The company has a broad-based strategic alliance with the University of Massachusetts Medical School to develop novel compounds in the areas of ALS, obesity, type 2 diabetes and CMV using RNAi technology. CytRx also licensed from UMMS the rights to a DNA-based HIV vaccine technology currently in a Phase I clinical trial. The company also has a research program with Massachusetts General Hospital, Harvard University's teaching hospital, to use RNAi technology to develop a drug for the treatment of ALS. For more information, visit CytRx's website at

This press release may contain forward-looking statements within the meaning of Section 21E of the Securities Exchange Act of 1934, as amended, that involve risks and uncertainties that could cause actual events or results to differ materially from the events or results described in the forward- looking statements, including risks or uncertainties related to the early stage of CytRx's diabetes, obesity, CMV and ALS research, the need for future clinical testing of any RNAi-based products and small molecules that may be developed by CytRx, uncertainties regarding the scope of the clinical testing that may be required by regulatory authorities for the products acquired from Biorex and other products and the outcomes of those tests, the significant time and expense that will be incurred in developing any of the potential commercial applications for CytRx's RNAi technology or small molecules, CytRx's need for additional capital to fund its ongoing working capital needs, including ongoing research and development expenses related to the drugs purchased from Biorex, risks relating to the enforceability of any patents covering CytRx's products and to the possible infringement of third party patents by those products, and the impact of third party reimbursement policies on the use of and pricing for CytRx's products. Additional uncertainties and risks are described in CytRx's most recently filed SEC documents, such as its most recent annual report on Form 10-K, all quarterly reports on Form 10-Q and any current reports on Form 8-K filed since the date of the last Form 10-K. All forward-looking statements are based upon information available to CytRx on the date the statements are first published. CytRx undertakes no obligation to publicly update or revise any forward- looking statements, whether as a result of new information, future events or otherwise.

CytRx Corporation

CONTACT: Edward Umali of CytRx Corporation, +1-310-826-5648,[email protected]; or Investor Relations Group, Jane Lin or John Nesbett,+1-212-825-3210, for CytRx Corporation

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