November 5, 2014
By Riley McDermid, BioSpace.com Breaking News Staff
Rockwell Medical ‘s Triferic iron replacement therapy is facing renewed scrutiny today, after the U.S. Food and Drug Administration posted briefing documents from its panel last week assessing the drug on its official website earlier this week.
The notes show that the FDA remains concerned about the clinical usefulness of the data Rockwell presented, specifically how meaningful studies are to show Triferic will work as an iron replacement and treatment for maintenance of hemoglobin in kidney dialysis patients
Both the FDA and Rockwell agree that the two Phase III studies of Triferic have met their primary endpoints, which were maintaining hemoglobin levels at a pace comparable to a placebo. But the FDA said that because half of the dialysis patients in the studies dropped out before the end of the year-long treatment period, the data is statistically iffy.
“Consequently, there is a considerable amount of ‘missing data’ due to study drug discontinuation by the end of the study treatment period. It is noted that a large portion of the missing data due to withdrawn patients is due to protocol-mandated changes in anemia management, which were incorporated into the protocol to protect patient safety,” wrote the FDA.
“The large proportion of patients with early withdrawal from study treatment necessitates examination of the study data to assess impact of the early discontinuation of patients on the validity and robustness of the efficacy results,” said the notes posted Tuesday.
“Given the extent of subjects who withdrew from the study early (including protocol mandated drop-out) and differential reasons for such early withdrawal, does the primary efficacy endpoint analysis adequately capture the benefit of the treatment? If yes, is the benefit of the treatment well estimated/established?” it said. But despite the queries from the FDA, Rockwell’s stock was climbed Tuesday by almost 14 percent, only to dip a bit in morning trading Wednesday. A blogger at The Street theorized this was because the FDA’s notes were so clear-cut that it may be paving the way for a provisional approval of Triferic later in the week.
The FDA also took issue with a third study Rockwell presented, which was designed to show Triferic’s could reduce the use of costly ESAs by dialysis patients. “FDA analyzed the data from this study, dubbed “PRIME,” and basically threw out the results,” said The Street.
“Because of the inconsistent efficacy results and exploratory nature of the study, the submitted data is insufficient to support the proposed second indication to reduce the prescribed dose of ESA required to maintain desired hemoglobin levels,” said the FDA in its notes.
