A Head-to-Head Comparison of the Safety and Efficacy of Ferumoxytol to Iron Sucrose for the Treatment of Iron Deficiency Anemia

Iron replacement therapy is essential for increasing iron stores and raising hemoglobin levels in patients with iron deficiency anemia (IDA). Oral iron supplements have limited absorption and are commonly associated with gastrointestinal (GI) side effects that reduce compliance, resulting in limited increases in hemoglobin. In patients without chronic kidney disease (CKD), oral iron therapy is frequently used to treat IDA. However, when oral iron therapy is unsatisfactory or cannot be tolerated, intravenous (IV) iron therapy may be appropriate. In the US, iron dextrans are the only approved IV iron products indicated for the treatment of IDA in non-CKD patients, and have limitations around convenience because they require a test dose and as many as 10 administrations via a slow infusion; iron dextrans have also been associated with a relatively high rate of serious adverse reactions compared to other IV iron products. Other IV irons, such as iron sucrose and sodium ferric gluconate, are only approved in the US for the treatment of IDA in patients with CKD. Like the iron dextrans, both of these products are limited by administration, requiring 5 to 10 clinic visits for the administration of a full therapeutic dose (1 gram of iron). Feraheme® (ferumoxytol) Injection is an IV iron product approved in the US for the treatment of IDA in adult subjects with CKD. Its carbohydrate coating is designed to minimize immunological sensitivity, and it has less free iron than other IV iron preparations. Ferumoxytol is administered as two IV injections of 510 mg (17 mL) 3 to 8 days apart for a total cumulative dose of 1.02 g.

To date, there have been a limited number of studies that have examined the safety and efficacy of IV irons in a head-to-head manner for the treatment of IDA, and no study has done so in a large number of subjects or in a broad patient population. AMAG, therefore, has initiated a randomized, controlled trial (ClinicalTrials.gov NCT01114204) to compare ferumoxytol with iron sucrose. Iron sucrose is approved in many countries outside the US for the treatment of IDA in patients intolerant to oral iron therapy, and is considered a safer alternative to IV iron dextran. This open-label trial (n=600) will evaluate the efficacy and safety of a 1.02 g of IV ferumoxytol, administered as 2 doses of 510 mg each, compared with 1.0 g of IV iron sucrose, administered as 5 doses of 200 mg each. Enrolled subjects will have IDA associated with a variety of underlying conditions including abnormal uterine bleeding, GI disorders, cancer, postpartum anemia, and others (eg, nutritional deficiency). Endpoints include changes in hemoglobin and transferrin saturation at Week 5, as well as evaluation of the requirement for erythropoiesis stimulating agent therapy and blood transfusion. Patient reported outcomes instruments will be employed to assess the impact of IV iron therapy on anemia symptoms and health-related quality of life (fatigue, energy, etc). Additionally, detailed information on healthcare utilization will be collected.

In the US, non-CKD patients with IDA who have a history of unsatisfactory oral iron therapy have limited options for iron replacement therapy. Study NCT01114204 will provide novel information comparing the safety and efficacy of two IV iron therapies for the treatment of IDA in a broad patient population.

Poma:AMAG Pharmaceuticals, Inc.: Employment. Diana:AMAG Pharmaceuticals, Inc.: Employment. McLaughlin:AMAG Pharmaceuticals, Inc.: Employment. Kausz:AMAG Pharmaceuticals, Inc.: Employment.