Positive preliminary results from Feraheme phase III study on iron deficiency anemia

AMAG Pharmaceuticals, Inc. (NASDAQ: AMAG) today reported preliminary results from the second phase III study from its global registrational program for Feraheme® (ferumoxytol) in patients with iron deficiency anemia (IDA) regardless of the underlying cause. The study being reported today, IDA-301, compared Feraheme treatment to placebo and enrolled 808 patients at 136 sites in the US, Canada, India, Latvia, Hungary, and Poland. The patients enrolled in the study had a history of unsatisfactory response to, or could otherwise not tolerate, oral iron therapy. Patients in this study had IDA associated with various conditions including abnormal uterine bleeding, cancer, gastrointestinal disorders or other causes. Feraheme demonstrated superiority on all primary efficacy endpoints evaluated in this study. The efficacy and safety of Feraheme in this study were comparable to that reported earlier this year in the IDA-302 study, the phase III IDA study comparing Feraheme to iron sucrose.    

The IDA-301 study was a double-blind, placebo-controlled trial that randomized patients 3:1 to receive a one gram IV course of Feraheme or placebo, and it was powered to demonstrate superiority on efficacy. In this study, 608 patients were treated with Feraheme and 200 received placebo, with the demographics and all baseline parameters well balanced between the two treatment groups. The primary efficacy endpoint of the study for US regulators is the proportion of subjects who achieved a ≥ 2.0 g/dL increase in hemoglobin at any time from baseline to week five; the primary efficacy endpoint of the study for EU regulators is the mean change in hemoglobin from baseline to week five. Patients enrolled in this study were eligible to enter an ongoing extension study, IDA-303, to evaluate repeat dosing with Feraheme; the extension study is fully enrolled with 634 patients.

In the IDA-301 study, Feraheme demonstrated robust efficacy, achieving superiority on both primary efficacy endpoints. Patients treated with Feraheme achieved a statistically significant mean increase in hemoglobin at week five of 2.7 g/dL, compared to a mean increase of only 0.1 g/dL in patients who received placebo; importantly, these data are consistent with the 2.7 g/dL increase in hemoglobin reported in the IDA-302 study. In addition, a ≥ 2.0 g/dL increase in hemoglobin at any time from baseline to week five was achieved in a statistically significantly greater proportion, 81.1%, of patients treated with Feraheme in this study, compared with only 5.5% of patients who received placebo; these data are also consistent with the data from IDA-302, in which 84.0% of Feraheme-treated patients achieved a ≥ 2.0 g/dL increase in hemoglobin. Further, a statistically significant improvement in fatigue, as assessed by patient reported outcome measures, was demonstrated at week five in Feraheme-treated patients.

No new safety signals were observed with Feraheme and the types of reported adverse events (AEs) were consistent with those seen in both the previously reported IDA phase III study and the CKD phase III studies, and those contained in the approved U.S. package insert for Feraheme. Overall, AEs were reported in both study arms with AEs reported in 49.2% of Feraheme-treated patients, compared to 43.0% of patients who received placebo.

Patients in both groups experienced protocol-defined adverse events of special interest, which included mild to severe hypotension or hypersensitivity reactions ranging from fever alone to an anaphylactoid reaction; 3.6% of Feraheme-treated patients experienced adverse events of special interest compared to 1.0% of patients who received placebo. Cardiovascular AEs were reported in 0.8% of Feraheme-treated patients, all of which were considered unrelated to study drug by the investigators, and none were reported in the placebo group. Serious adverse events (SAEs) were reported at a comparable frequency in both Feraheme-treated patients (2.6%) and patients who received placebo (3.0%); four of the SAEs in Feraheme-treated patients (0.7%) were reported as related to study drug by investigators. The percent of Feraheme-treated patients that experienced an SAE in this study (2.6%) was lower than that previously reported in the IDA-302 study (4.2%), and comparable to the rate of SAEs in iron sucrose-treated patients (2.5%) in that study.

"We are very pleased that, consistent with the results from IDA-302, Feraheme achieved all primary efficacy endpoints in this study and no new safety signals were identified," said Lee F. Allen, MD, Ph.D., chief medical officer of AMAG. "With both phase III studies in our global registrational program for Feraheme now complete, we will seek approval for Feraheme for the treatment of a broader population of patients with iron deficiency anemia and a history of an unsatisfactory response to oral iron therapy. As demonstrated in this study through patient reported outcomes, we believe that Feraheme could provide an important clinical benefit with an improvement in the quality of life for this patient population, and could be a valuable therapeutic alternative to currently approved IV irons for the treatment of their iron deficiency anemia."

AMAG is planning to submit a supplemental new drug application for the broad IDA indication to the U.S. Food and Drug Administration by year-end 2012.