ASH Clinical News ACN_4.12_SUPP_web | Page 10

DRAWING FIRST BLOOD and it means we are wasting a lot of money by using a drug available only in a 750-mg vial. If we had the luxury of having the European vial sizes of 500 mg and 1,000 mg available in the U.S., then this entire argument goes away. In the U.S., a 750-mg vial of FCM costs $538; in the U.K., a 1,000-mg vial costs approximately $156. So, other high-resource countries are paying a fraction of what U.S. clinicians are paying for the same drug. I don’t understand why, in the U.S., we are stuck with a 750-mg vial of FCM. We are wasting a lot of money by using a drug available only in a 750-mg vial, which costs $538, versus giving a 1,000-mg dose of LMWID in one sitting, which will cost $240. ”If we had the luxury of having the European vial sizes ... available in the U.S., then this entire argument goes away.” —MICHAEL AUERBACH, MD Dr. Boccia: FCM is a great, safe option, and it is nice to be able to administer an iron therapy in 15 minutes. At times, I use one vial of FCM, rather than using a second vial to deliver 750 mg. Also, in lighter-weight patients, I will administer 500 mg of a 750-mg vial; then, if the patient appears to have an iron deficit lower than 1,500 mg, I will give them one 750-mg dose and monitor their response over time. Dr. Auerbach: That’s a prudent clinical paradigm, and one that we have to consider because of the pricing. I might argue for the use of FCM in iron-deficient pregnant women, but, because of the costs, I think we have to explore other options for administering IV iron. We recently compared the safety and efficacy of ferumoxy- tol 1,020 mg and FCM 1,500 mg in nearly 2,000 patients with iron-deficiency anemia and found that each product performed similarly. 5 The safety was equivalent, with similar rates of moderate-to-severe hypersensitivity reactions up to five weeks after treatment (0.6% for ferumoxytol and 0.7% for FCM). The efficacy also was equivalent, with baseline hemoglobin levels improving by 1.4 g/dL and 1.6 g/dL, respectively, at week five. These results were similar even though the FCM dose was nearly 50-percent higher than the ferumoxytol dose. The trial also suggested that we are not able to use more than 1,000 mg in a short period of time. That is consistent with in vitro 8 Focus on Classical Hematology data. Unfortunately, we don't know what happens to IV iron after administration because we haven’t had any in vitro data to answer these questions. Dr. Boccia: At this time, research shows that we can correct a patient’s anemia to a similar degree with different IV iron formulations, but it doesn’t tell us whether the patient’s underlying iron deficiency can be corrected better with one form of IV iron over another or one dose over another, and – importantly – if one dose might result in a more durable correction in that population of patients with repeated need. Dr. Auerbach: In the FIRM study, when we monitored Hb and transferrin levels five weeks from baseline and there was no difference between patients treated with FCM or ferumoxytol. Dr. Boccia: And that is only at five weeks. To answer the clinically important questions that would guide our therapy choice in this population, we also need trials with longer follow-up. The cutoff for follow-up in these studies ranges from 35 to 50 days. If we measure the levels at a fairly short interval, are those numbers going to be reflective of true iron stores? Or, has the iron restoration not completely occurred yet? I would like to have data through six months of follow-up to see when patients required retreatment with iron. Without those data, all we can do is speculate about the differences between doses. Dr. Auerbach: That’s an extremely important question, but, unfortunately, I’m not sure that we are going to get those data. I can’t recall anything in the existing literature to support or refute that claim. I think our only disagreem