Several markers of disease progression were followed throughout the open-label extension clinical trial, including the ALSFRS-R, vital capacity, total body weight and body mass index (a measure of obesity). In the absence of placebo control, CytRx chose to compare the open-label clinical trial results with the placebo group of a recently-published clinical trial (Cudkowicz, M.E., et. al., Annals of Neurology 2006 volume 60:22-31) that enrolled patients with very similar characteristics. While difficult to draw definitive conclusions without a concurrent placebo control group, there was an apparent trend toward a slower decline in every disease progression marker in the arimoclomol open-label clinical trial compared with the historical placebo control. In the trial, CytRx observed a decrease in the rate of decline of 21% for ALSFRS-R, 8.0% for vital capacity, 23% for total body weight and 20% for body mass index when compared with that historical control.
Based on safety data from a previously announced rising multiple dose clinical trial, CytRx plans to commence its Phase IIb clinical trial later this y ear with a four-fold arimoclomol dose increase, subject to FDA clearance.
"We are encouraged by the favorable results of this open-label trial, which make us even more eager to proceed at an even higher dose level in further clinical testing," stated CytRx's President and CEO Steven A. Kriegsman. "The comparison of these clinical results with historical data suggests a trend toward clinical improvement. Our Phase IIb efficacy study will be placebo-controlled and is planned to include a larger number of volunteers, treated for a longer period of time with a four-fold higher dose than that used in the open-label clinical trial."
The open-label extension clinical trial was initiated in February 2006 as ALS volunteers completing CytRx's placebo-controlled, double-blind, dose-ranging Phase IIa clinical trial were provided the opportunity to receive arimoclomol treatment for up to an additional six months. A total of 69 patients were treated in the open-label arimoclomol trial for six months, while the historical control followed 99 subjects for 12 months.
In the open-label trial, arimoclomol treatment was demonstrated to be safe as indicated by the lack of clinically-significant changes in vital signs and laboratory values, compared to baseline values. Arimoclomol was also well-tolerated with a total drop-out rate of 11.6%, or an average of 1.3% per month, during the six-month trial. This compares favorably with the historical control drop-out rate of 33.3%, or an average of 2.75% per month, for the 12-month trial.
CytRx's planned Phase IIb clinical trial is currently expected to include approximately 390 ALS patients enrolled at 30 to 35 U.S. and Canadian clinical sites treated for nine months. The trial is expected to be completed approximately 18 months after enrollment begins.
About CytRx Corporation
CytRx Corporation is a biopharmaceutical research and development company engaged in the development of high-value human therap eutics. 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 plans to enter a Phase IIb clinical trial with arimoclomol in ALS in the second half of 2007, subject to FDA clearance. Based on preliminary discussions with the FDA, CytRx is now considering a second efficacy clinical trial for ALS, possibly in parallel with the upcoming Phase IIb trial, to provide additional efficacy data to support a possible approval decision by the FDA.
The FDA has granted Fast Track designation and Orphan Drug status to arimoclomol for the treatment of ALS, which has also been granted orphan medicinal product status for the treatment of ALS by the European Commission. The Company has announced plans to commence a Phase II clinical trial for arimoclomol in stroke recovery in the first half of 2008, subject to FDA clearance. The Company has also announced plans to commence a Phase II clinical trial with its next drug candidate, iroxanadine, for diabetic foot ulcers in the first half of 2008, subject to FDA clearance. In addition, the Company plans to open a research and development facility in San Diego in the third quarter of 2007. 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, 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 chem istry 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.
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 regarding regulatory approvals for future clinical testing of arimoclomol, including CytRx's planned Phase IIb clinical trial, and the scope of the clinical testing that may be required by regulatory authorities for arimoclomol, risks related to any comparison of clinical data to historical controls in the absence of concurrent placebo controls, uncertainties regarding the timing and amount of revenues, if any, that will be realized by CytRx from the commercialization of arimoclomol, the significant time and expense that will be incurred in developing any of the potential commercial applications for arimoclomol and the potential need for additional capital to fund the development of arimoclomol, as well as other risks or uncertainties described in CytRx's most recently filed SEC documents, such as its most recent annual report on Form 10-K 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 informat ion 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.
Dan Schustack, 212-732-4300