CytRx Corporation Initiates ALS Open-Label Extension Trial As First Patient Completes Arimoclomol Phase II Clinical Trial

LOS ANGELES, Feb. 13 /PRNewswire-FirstCall/ -- CytRx Corporation , a biopharmaceutical company engaged in the development and commercialization of human therapeutics, today reported that it has enrolled the first patient in an open-label extension clinical trial with its lead small molecule product candidate arimoclomol for the treatment of amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease).

In January 2005, CytRx announced filing of a clinical protocol with the U.S. Food and Drug Administration (FDA) to allow ALS patients who have completed the Company's Phase IIa clinical trial to receive treatment with orally-administered arimoclomol at the highest of the three Phase IIa dose levels for up to an additional six months. The open-label extension trial is designed to provide additional safety and tolerability data in combination with the current Phase IIa trial.

"We are delighted that the first ALS patient completing our Phase IIa trial has decided to join our open-label extension trial, which was designed to make arimoclomol freely available to ALS patients who have few alternatives for the treatment of this progressive neurodegenerative disease. Now, even those patients who were randomly assigned to the Phase IIa trial placebo group have the opportunity to receive the potential therapeutic value of arimoclomol. We expect enrollment in the open-label extension trial to increase as more patients complete the Phase IIa trial," said Steven A. Kriegsman, President and CEO of CytRx.

The Company today further announced that it is on track to complete enrollment this quarter in its 80-patient, multicenter, double-blind, placebo- controlled Phase IIa clinical trial with arimoclomol for the treatment of ALS. To date, of the 80 patients who have been screened for participation, 59 have started the treatment regimen. Patients receive either placebo (a capsule without drug) or one of three dose levels of arimoclomol capsules three times daily for a period of 12 weeks. The primary endpoints for this trial are safety and tolerability. Secondary endpoints include a preliminary evaluation of efficacy using two widely accepted surrogate markers, the revised ALS Functional Rating Scale (ALSFRS-R), which is used to determine patient's capacity and independence in 13 functional activities, and Vital Capacity (VC), an assessment of lung capacity. The trial is powered to monitor only extreme responses in these two categories. In 2005 arimoclomol was granted Orphan Drug status and Fast Track designation for the treatment of ALS from the FDA.

"We continue to receive strong interest from ALS patients to enroll in this trial. All 10 participating clinical sites throughout the United States are now actively recruiting and dosing patients, spurring a rapid increase in the enrollment rate," explained Mr. Kriegsman.

CytRx expects to report final data from its Phase IIa trial in the third quarter of this year, followed by initiation of a potentially pivotal Phase IIb clinical trial, subject to FDA review and acceptance. The Phase IIb trial will be powered to detect more subtle efficacy responses than the current trial. Although this second trial is still in the planning stages, it is expected to include approximately 300 ALS patients recruited from 25 clinical sites. The Company believes that successfully demonstrating safety and efficacy in this latter Phase II clinical trial could be sufficient to support product registration with the FDA.

About ALS

ALS is a progressive degeneration of the brain and spinal column nerve cells that control the muscles that allow movement. Over a period of months or years, ALS causes increasing muscle weakness, inability to control movement and problems with speaking, swallowing and breathing. According to the ALS Survival Guide, 50% of ALS patients die within 18 months of diagnosis and 80% die within five years. In the U.S., an estimated 30,000 people are living with ALS and nearly 6,000 new cases are diagnosed annually, according to the ALS Association. There are more than 120,000 people living with ALS worldwide.

About CytRx Corporation

CytRx Corporation is a biopharmaceutical research and development company engaged in the development of products. The Company owns three clinical-stage compounds based on its small molecule "molecular chaperone" co-induction technology, as well as a targeted library of 500 small molecule drug candidates that may be used to screen for new drug candidates. CytRx has initiated a Phase II clinical trial with its lead small molecule product candidate arimoclomol for the treatment for amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease). CytRx has previously announced that a novel HIV DNA + protein vaccine exclusively licensed to CytRx and developed by researchers at UMMS and Advanced BioScience Laboratories, and funded by the National Institutes of Health, demonstrated very promising interim Phase I clinical trial results that indicate its ability to produce potent antibody responses with neutralizing activity against multiple HIV viral strains. For more information, visit CytRx's Web site at www.cytrx.com.

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. Examples of such statements include, but are not limited to, statements relating to the expected timing, scope and results of our clinical development and research programs, including the initiation of clinical trials, and statements regarding the potential benefits of our drug candidates and potential drug candidates. 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 and timing of CytRx's Phase II clinical trial for arimoclomol, including the open-label extension of that trial, uncertainties regarding regulatory approvals for future clinical testing of arimoclomol and the scope of the clinical testing that may eventually be required by regulatory authorities for arimoclomol, CytRx's need for additional capital to fund its ongoing working capital needs, including its planned Phase IIb clinical trial for arimoclomol, uncertainties related to the early stage of CytRx's diabetes, obesity, cytomegalovirus and ALS research, the need for future clinical testing of any RNAi-based products and small molecules that may be developed by CytRx, 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, 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.

For Additional Information: CytRx Corporation: Ed Umali (eumali@cytrx.com) Director of Corporate Communications (310) 826-5648, ext. 309 CEOcast, Inc. Investor Contacts: Kevin Theiss (ktheiss@ceocast.com) Cormac Glynn (cglynn@ceocast.com) (212) 732-4300

CONTACT: Ed Umali, Director of Corporate Communications of CytRxCorporation, +1-310-826-5648, ext. 309, eumali@cytrx.com; or Investors,Kevin Theiss, ktheiss@ceocast.com, or Cormac Glynn, cglynn@ceocast.com,both of CEOcast, Inc., +1-212-732-4300, for CytRx Corporation

Web site: http://www.cytrx.com//