CytRx Provides Operational Update.

Plans to significantly expand research and clinical development programs with molecular chaperone technology

Phase II clinical trial for stroke recovery expected to commence in first half of 2008

LOS ANGELES -- CytRx Corporation (NASDAQ:CYTR) today announced plans to expand its research and development of therapeutic products based on its novel, orally-administered molecular chaperone amplification technology, including broadening its clinical focus beyond the treatment of diseases related to the central nervous system. CytRx also announced its intent to open a San Diego-based research and development facility in the third quarter of 2007 to provide it with a dedicated laboratory to accelerate its molecular chaperone drug development programs.

CytRx is planning to initiate in the first half of 2008 a Phase II clinical trial with its lead molecular chaperone-based drug candidate arimoclomol in patients for stroke recovery. In April 2007, CytRx announced favorable results from a stroke functional recovery study that showed arimoclomol accelerated neurological recovery when administered up to 48 hours following stroke inducement in a rat model.

CytRx also remains on schedule with plans to begin a Phase IIb clinical trial in the second half of this year with arimoclomol for the treatment of amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease), subject to U.S. Food and Drug Administration (FDA) clearance. Given the severity of ALS and the lack of therapeutic treatment options, CytRx believes that positive efficacy and safety results from this clinical trial could form the primary basis of an efficacy claim for a New Drug Application for arimoclomol for this indication.

"Our decision to expand research and clinical development of our molecular chaperone platform technology is based on promising clinical and pre-clinical results and this technology's believed novel mechanism of action that holds potential promise in treating an extremely broad field of diseases, many representing large market opportunities," said Jack Barber, Ph.D., CytRx's Chief Scientific Officer, responsible for overseeing CytRx's molecular chaperone programs. "Studies conducted with arimoclomol and iroxanadine provide what we believe to be scientifically reliable support for the development of drug candidates that are capable of enhancing the body's natural protein repair process."

To function normally in a cell, proteins must fold into particular three-dimensional shapes. During stressful conditions, such as certain disease states, proteins can fold into inappropriate shapes that can be toxic to the cell. To protect itself from damage, the cell activates the cellular stress response. Among the most important components of the stress response is the production of molecular chaperone proteins that have the ability to refold a protein into a non-toxic shape or recruit other proteins that have the ability to "tag" the toxic protein for destruction.

"I am very excited about CytRx's specific focus on our highly-promising molecular chaperone platform and I believe this direction will provide us with a pathway to build a significant company in the biotechnology sector," said CytRx's President and CEO Steven A. Kriegsman. "We are well-positioned to pursue our platform development activities based on a financing completed last month that added more than $19 million to our balance sheet and also the receipt of significant proceeds from the exercise of options and warrants this year.

"With our reported $15 million contribution to our majority-owned subsidiary RXi Pharmaceuticals Corporation, we have reached our corporate objective of providing a means to unlock the intrinsic value of our RNAi assets for our stockholders, while concurrently affording us greater bandwidth to focus on our molecular chaperone amplification technology," he added. "Since co-founding RXi, we have experienced significant interest in the RNAi platform technology from leaders in the pharmaceutical, biotechnology and scientific communities. As previously announced, we plan as soon as possible to reduce CytRx's ownership position in RXi to less than a majority, and to provide our stockholders with direct ownership of a part of that company.

"We are also announcing that we have mutually agreed with Dr. Mark Tepper, who has been serving as our Senior Vice President - Drug Discovery, that he will cease to serve in that position. Dr. Tepper has agreed to continue working with CytRx in a consulting position over the coming months, after which he will pursue other endeavors," said Mr. Kriegsman. "We thank Dr. Tepper for his past contributions to the development of CytRx, and are pleased that he will work with us to transition our programs to our new San Diego facility."

CytRx plans to transfer its research facilities in Worcester, Massachusetts to RXi. RXi intends to pursue development of therapies for metabolic disorders previously targeted by CytRx as part of its strategy to develop and commercialize therapeutic products based upon RNAi technologies for the treatment of human diseases, with an initial focus on neurodegenerative diseases, cancer, type 2 diabetes and obesity. In addition, CytRx has no immediate plans to develop the HIV + DNA protein vaccine created by researchers at the University of Massachusetts Medical School and Advanced BioScience Laboratories, which is exclusively licensed to CytRx. CytRx will explore possible out-licensing, alliance or sale of the HIV + DNA protein vaccine asset.

Background on Arimoclomol for ALS

CytRx plans to begin a Phase IIb trial in the second half of this year, subject to FDA clearance. This trial, currently expected to include approximately 390 ALS patients enrolled at 30 to 35 clinical sites in the U.S. and Canada, will be designed to monitor changes in disease progression and should be completed about 18 months after patient enrollment begins. CytRx believes that positive efficacy and safety results from the Phase IIb clinical trial could form the primary basis of an efficacy claim for a New Drug Application for arimoclomol for this indication.

CytRx is currently completing a maximum dose study with arimoclomol that will assist in selecting the highest tolerated dose level for incorporation into the protocol for the Phase IIb trial in ALS. The dose escalating study is being performed under the assumption that the highest tolerated dose level of arimoclomol will provide the greatest therapeutic benefit.

CytRx has completed an open-label extension study based on its Phase IIa trial and expects to announce results of this study in the current quarter. This study was performed to allow ALS patients the opportunity to continue treatment for a six-month extended period with arimoclomol at the highest dose level provided for in the Phase IIa study. The open-label extension study is expected to provide additional safety data on arimoclomol in ALS patients.

In September 2006, CytRx announced receipt of $24.5 million in a non-dilutive agreement with the privately funded ALS Charitable Remainder Trust to fund continued arimoclomol development for the treatment for ALS in return for a 1% royalty from potential worldwide sales of arimoclomol for the treatment of ALS. The Greater Los Angeles Chapter of The ALS Association is the charitable beneficiary of the ALS Charitable Remainder Trust.

Arimoclomol for the treatment of ALS has been granted Fast Track designation and Orphan Drug status by the FDA and orphan medicinal product status by the European Commission.

Background on Arimoclomol for Stroke

In April 2007, CytRx announced positive results of animal stroke studies indicating that arimoclomol significantly accelerated the recovery of sensory and motor function in an experimental rat model of stroke, even when treatment was withheld as long as 48 hours after stroke was induced. These data confirm and expand upon preclinical data announced late in 2006. The flexibility to administer arimoclomol for delayed intervention is an advantage compared with currently-marketed drugs for the treatment of stroke and, if efficacious, arimoclomol may allow substantial penetration into the $58 billion stroke market. CytRx is currently planning a potential Phase II clinical trial with arimoclomol in stroke patients.

About CytRx Corporation

Los Angeles, California-based CytRx Corporation is a biopharmaceutical research and development company engaged in the development of high-value human therapeutics. The Company owns three clinical-stage compounds based on its small molecule "molecular chaperone" co-induction technology. In September 2006 CytRx announced that arimoclomol was shown to be safe and well tolerated at all three doses tested in its Phase IIa clinical trial in patients with ALS. The Company expects to announce results of its completed open-label extension trial in the second quarter of 2007. The Company plans to enter a Phase IIb clinical trial with arimoclomol in ALS in the second half of 2007, subject to U.S. Food and Drug Administration (FDA) clearance. The FDA has granted Fast Track designation and Orphan Drug status to arimoclomol for the treatment of ALS and has also been granted orphan medicinal product status for the treatment of ALS by the European Commission. The Company is also developing a potential Phase II clinical plan for arimoclomol in stroke recovery. For more information on the Company, visit www.cytrx.com.

About RXi Pharmaceuticals Corporation

Worcester, Massachusetts-based RXi Pharmaceuticals Corporation, a majority-owned subsidiary of CytRx Corporation, is a biopharmaceutical research and development company that focuses on developing RNAi-based therapeutics for the treatment of human disease. RXi's initial focus is on neurodegenerative diseases, oncology, type 2 diabetes and obesity. RXi has licenses to a diverse series of early patents and patent applications that were filed from 1998 to 2006 in the areas of RNAi target sequences, RNAi chemistry and RNAi delivery. The company was founded by CytRx and RNAi pioneers Craig Mello, Ph.D., 2006 Nobel Laureate for discovering RNAi and inventing RNAi therapeutics, Tariq M. Rana, Ph.D., inventor of fundamental technology for stabilizing RNAi and of RNAi nanotransporters, Greg Hannon, Ph.D., discoverer of RNAi mechanism (RISC) and short hairpin RNAi (shRNAi), and Michael Czech, Ph.D., a leader in the application of RNAi to diabetes and obesity. RXi's CEO, Tod Woolf, Ph.D., previously co-invented and commercialized STEALTH[TM] RNAi, one of the most widely used second-generation RNAi research products.

Forward-Looking Statements

This press release may contain forward-looking statements within the meaning of Section 21E of the Securities Exchange Act of 1934, as amended. Such statements 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 outcome or results of any future pre-clinical or clinical testing of CytRx's molecular chaperone technology and drug candidates, including arimoclomol and iroxanadine, the early stage of development of RXi's technology, and the scope, timing and outcome of pre-clinical and clinical testing and regulatory review of RXi's potential products, and other risks or uncertainties 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.