December 4, 2018 New study demonstrates significant difference between iron isomaltoside and ferric carboxymaltose on hypophosphatemic effects in a controlled, randomized clinical investigation

Results of a study comparing the incidence of hypophosphatemia after high dose IV iron substitution have been presented at the 60th annual meeting of the American Society of Hematology. The HOMe aFers trial recruited women with gynaecological bleeding and subsequent iron deficiency. All subjects were given high dose intravenous iron, randomised between iron isomaltoside and ferric carboxymaltose to correct their iron deficiency. It has been reported[1] that ferric carboxymaltose has a propensity to induce hypophosphatemia. This independent study was conducted by Prof Gunnar Heine (formerly University of Saarland, Homburg, Germany, now Agaplesion Markus Krankenhaus, Frankfurt, Germany) to investigate whether this hypophosphatemic effect is substance-specific or whether it was a general occurrence after high dose iron administration. 

Women with iron deficiency anaemia due to heavy menstrual bleeding entered the trial with serum phosphate levels within the normal range; each subject was randomised to receive 1000 mg of either iron isomaltoside or ferric carboxymaltose. The primary endpoint was the incidence of hypophosphatemia defined as plasma phosphate < 2.0 mg /dl at, at least, one out of three of post-infusion time points (day 1, day 8, week 5). An interim analysis of 25 women who completed the study showed that 9 out of 12 women receiving ferric carboxymaltose developed hypophosphatemia (75.0%) with only one incidence in the iron isomaltoside group (1 out of 13, 7.7%) (p = 0.001). Furthermore, the minimum plasma phosphate levels at any post-infusion time-point were significantly lower in the ferric carboxymaltose group (1.8 ± 0.3 mg/dl) vs iron isomaltoside (2.7 ± 0.6 mg/dl) (p < 0.001). As expected both study groups showed an increase in haemoglobin and ferritin after the iron infusion and there were no severe adverse events in either group. 

Gunnar Heine MD, lead investigator on the HOMe aFers trial, said: “This study clearly indicates that IV iron-induced hypophosphatemia is not a general effect of high dose iron infusion, but is substance-specific to ferric carboxymaltose.” 

Lars Lykke Thomsen, Chief Medical Officer at Pharmacosmos, said: “These results confirm what our own studies have shown; that in contrast to ferric carboxymaltose, iron isomaltoside does not have a profound effect on phosphate levels, and suggest that iron isomaltoside can be given to treat iron deficiency without the risk of inducing significant hypophosphatemia.”

[1] Zoller et al. Curr Opin Nephrol Hypertens 2017;26(4):266–275


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About Monofer®

Monofer® (iron isomaltoside 1000 for injection) is an iron-carbohydrate complex for intravenous administration. Monofer® is marketed in more than 30 countries worldwide for the treatment of iron deficiency and iron deficiency anaemia. Monofer® is manufactured by Pharmacosmos A/S, Denmark.

About Iron Deficiency

Iron deficiency anaemia (IDA) is a debilitating condition that affects almost 2 billion people worldwide. IDA is often associated with many chronic disorders such as renal diseases (including Chronic Kidney Disease), cancers (including chemotherapy-induced anaemia), gynaecologic disorders (including abnormal uterine bleeding) and inflammatory bowel disease (IBD).

About Pharmacosmos

Headquartered in Denmark, Pharmacosmos is a family-owned, international healthcare company with more than 50 years of innovation and leadership in iron- and carbohydrate-based treatments and solutions for human and animal use.

A research-based company, its ongoing R&D programme focuses on improving the lives of patients with iron deficiency with or without anaemia. More than 1 billion people live with iron deficiency anaemia and it is the leading cause of death for an estimated 180,000 people every year. This makes it one of the largest global health challenges of our time.

Pharmacosmos has subsidiaries in US, UK, Ireland, Germany, Sweden and Norway and its products are marketed in more than 80 countries around the world. Its manufacturing facilities are approved, among others, by the Danish Medicines Agency and the US FDA.