Keryx Biopharmaceuticals, Inc. (Nasdaq: KERX) announced today the initiation of its short-term Phase 3 study of Zerenex™ (ferric citrate), the Company's iron-based phosphate binder for the treatment of elevated serum phosphorous levels, or hyperphosphatemia, in patients with end-stage renal disease on dialysis. The initiation of this study marks the commencement of the Company's Phase 3 registration program for Zerenex, which is being conducted in accordance with a Special Protocol Assessment (SPA) agreement with the FDA. Pursuant to the Company's SPA agreement, the Zerenex Phase 3 registration program will consist of the short-term efficacy study initiated today, and 58-week long-term safety and efficacy study, to be initiated in the third quarter of 2010. Patients completing the short term study are eligible to be enrolled into the long-term study.
The short-term efficacy study initiated today is a multicenter, randomized, open-label clinical trial with a planned enrollment of approximately 150 patients on hemodialysis. All patients will undergo a 2-week washout period, following which the patients will be randomized 1:1:1 to receive a fixed dose of Zerenex (1 gram, 6 grams or 8 grams per day) for a treatment period of 28 days. The primary endpoint of the study is to demonstrate a dose response in the change of serum phosphorous from baseline (end of washout period) to end of the treatment period (day 28). Approximately 15 sites in the U.S. will participate in the study. Patient enrollment is expected to take up to 6 months, with study completion expected by the end of 2010.
Dr. Julia Lewis, Professor of Medicine, Department of Nephrology, Vanderbilt University School of Medicine, and member of the Executive Committee of the Collaborative Study Group, will be the Study Chair of the Zerenex Phase 3 registration program. Dr. Samuel S. Blumenthal, Professor of Medicine at Medical College of Wisconsin, will serve as the study's Co-Principal Investigator.