WIXOM, Mich.—Rockwell Medical announced successful topline results from the PRIME clinical study of Soluble Ferric Pyrophosphate (SFP), its investigational iron-delivery drug currently in Phase 3 clinical studies for the treatment of iron deficiency in hemodialysis patients. The PRIME study demonstrated that regular administration of SFP-iron via dialysate reduced the usage of erythropoietin stimulating agents (ESAs) during hemodialysis by 37.1 percent while maintaining iron balance and maximizing iron delivery.
The PRIME study was a nine-month, prospective, randomized, placebo-controlled, double-blinded, multi-center study in United States that randomized 108 patients equally to dialysate containing SFP-iron versus conventional dialysate. A total of 103 patients received blinded study drug (52 SFP, 51 Placebo; modified ITT population). In each group, 11 subjects discontinued prematurely. Discontinuations due to adverse events were two in SFP and three in placebo. The reasons for the remaining discontinuations were similar between treatment groups. The baseline hemoglobin was similar in both groups (10.9 g/dL SFP and 11.1 g/dL placebo). In all study patients, ESA doses were titrated to maintain hemoglobin in a target range of 9.5 to 11.5 g/dL according to an algorithm managed by an independent centralized anemia management group. At the end of treatment, the hemoglobin value in the SFP group was 10.5 g/dL and 10.4 g/dL in the placebo group. Intravenous (IV) iron was administered as needed to treat iron deficiency.
The primary objective of the study was to determine whether regular administration of SFP via dialysate reduced the requirement for ESA dose by maintaining iron balance and optimizing iron delivery. The primary endpoint was the percent change in ESA dose from baseline to end of treatment (final two weeks of treatment period). Baseline ESA dose was similar between SFP (9448 U/wk) and placebo (9049 U/wk). In the modified ITT population, at the end of the study, ESA dose in the SFP arm was 10557 U/wk and placebo was 13345 U/wk. After adjusting for differences in baseline hemoglobin, the SFP arm required 37.1 percent less ESA dose compared to placebo. The difference between the two groups was statistically significant (p=0.034). The ESA sparing effect from SFP was observed without an increase in serum ferritin or transferrin saturation. A total of 32 patients received rescue IV iron, 20 in placebo and 12 in SFP. Further analysis of the complete data set is ongoing and the Company plans to submit PRIME data results for presentation at a major medical meeting later in 2013.
"We are very excited about the results of this well-run study. The 11µg/dL SFP dose delivered sufficient iron without increasing iron stores while greatly reducing ESA dose. The safety profile of SFP was similar to placebo and was well tolerated. In this study, a 37 percent higher ESA dose was needed in the placebo arm to maintain hemoglobin compared to the SFP arm, but in the Phase 3 CRUISE efficacy studies the ESA dose is kept constant, unable to be titrated, over the 12-month study period. The PRIME results support our belief that SFP will demonstrate efficacy in the Phase 3 CRUISE clinical studies by maintaining hemoglobin in the SFP arm while hemoglobin decreases in the placebo arm," said Dr. Raymond Pratt, chief medical officer of Rockwell Medical.
"We are extremely pleased with the results of the PRIME study. We believe that SFP's unique ability to treat iron deficiency while dramatically reducing the need for ESA, without increasing iron stores, strengthens SFP's potential to become the market leading iron therapy treatment for CKD-HD patients. SFP's ability to substantially reduce ESA use in the treatment of anemia should translate into significant cost savings in dialysis care while potentially lowering the serious risks associated with the dosing of ESAs. We sincerely thank the study investigators and coordinators, and our clinical team for a well-conducted PRIME study, and we look forward to the upcoming efficacy results from the Phase 3 CRUISE studies, which are expected to read-out in the 2nd-half of this year," Mr. Robert L. Chioini, chairman, CEO and president of Rockwell said.
SFP is a unique iron compound that is delivered to the hemodialysis patient via dialysate replacing the 5-7mg of iron lost during a dialysis treatment. SFP is introduced into the sodium bicarbonate concentrate that subsequently is mixed into dialysate. Once in the dialysate, SFP crosses the dialyzer membrane and enters the bloodstream where it immediately binds to apo-transferrin and is taken to the bone marrow. SFP mimics the way dietary iron is handled in the human body. In completed clinical trials to date, SFP has demonstrated that it can safely deliver iron and maintain hemoglobin levels, while decreasing ESA use without any increase in iron stores