"Intravenous Iron Sucrose Better Than Oral Iron Sulphate for Treatment of Anemia in Patients With Inflammatory Bowel Disease: Presented at UEGW"
By Chris Berrie
BERLIN, GERMANY -- October 31, 2006 -- Intravenous iron sucrose (Venofer(R)) is more effective and well tolerated in comparison with oral iron sulphate (Duroferon(R)), and it is the treatment of choice for anaemia due to iron deficiency in patients with inflammatory bowel disease (IBD), according to a multicentre, randomised, open study.
Stefan Lindgren, MD, PhD, Principal Investigator and Professor of Gastroenterology, Gastroenterology/ Hepatology Division, Department of Medicine, University Hospital MAS, Lund University, Malmö, Sweden, presented the study here on October 24[th at the United European Gastroenterology Week (UEGW).
"Anaemia due to iron deficiency is common in patients with IBD, and oral iron supplementation is often not tolerated by these patients," he indicated.
The objective of this study was to compare the effects of IV iron sucrose (IV iron) and prescribed oral iron sulphate (oral iron) supplementation in patients with Crohn's disease (CD) and ulcerative colitis (UC).
The study's primary objective was an increase in pathologically low hemoglobin (Hb). Patients were evaluated for plasma iron levels, quality of life, hematological and clinical chemistry parameters, vital signs and adverse events.
Eligibility criteria were non-active or relapsing CD and UC with blood Hb levels up to 115 g/L and serum ferritin below 300 mcg/L, with verified iron-deficient anemia and no other hematologic or systemic conditions, serum creatinine levels were less than 250 mcg/L, and no contraindications for IV or oral iron.
A total of 91 patients a mean of 42 years of age (male, 30%; CD/UC, 48/43) were enrolled; 45 were randomized to IV iron and 46 to oral iron. IV iron was dosed at 200 mg once or twice weekly according to the dosing formula for total iron deficit; oral iron was dosed at 200 mg twice daily.
Baseline clinical data were not significantly different between the IV and oral dosing groups for Hb (mean, 104.9 vs 103.8 g/L, respectively) and ferritin (mean, 14.0 vs 12.4 microg/L).
Mean accumulated dose for IV iron showed a linear increase to around 1,600 mg (estimated utilization, 100%) after 14 weeks of treatment, which then leveled off for the remaining treatment period. For oral iron, the mean accumulated dose remained linear to 30-fold that for IV iron, at 46,500 mg (estimated utilization, approximately 1.5%) at 20 weeks.
Over this 20-week duration, there were 7% (3 patients) withdrawals in the IV iron group, which were unrelated to iron treatment. In contrast, for oral iron, only 48% (22) tolerated full dose, with a further 28% (13) having dose reductions due to intolerance. Furthermore, there were 24% (11) withdrawals here due to intolerance (vs 0% for IV iron; P = .0009).
The end-of-treatment (20-week) responses saw a trend in Hb increases to >20 g/L in favor of IV iron over oral iron (66% vs 47%, respectively; P = .07), although this initially followed slightly lower Hb levels for IV iron to week 15 (with intention-to-treat population [ITT] as last observation carried forward [LOCF]). However, Dr. Lindgren said, "once again you have to bear in mind that these patients were given a very high maximum oral dose and a comparatively low dose of intravenous iron." Despite this, ferritin levels (as a measure of iron stores) of the ITT population (as LOCF) showed an approximately 2-fold increase in favor of IV iron within the first 10 weeks of treatment, he said.
Anaemia rates at end of treatment were significantly lower in the IV iron group compared with the oral iron group (16% vs 41%, respectively; P = .007), and the proportion of patients showing iron deficiency levels was significantly improved by IV iron treatment over oral iron (12% vs 41%; P = .002).
The mean reference Hb levels of 153 g/L for males and 133 g/L for females
were reached by 42% in the IV iron group (males, 27%; females, 37%) and 22%
in the oral iron group (males, 0%; females, 40%).
The most prevalent of adverse events reported on more than 2 occasions in the IV iron and oral iron groups where headache (6 vs 1) and upper respiratory tract infection (7 vs 2). Oral iron had more adverse events, with the most frequent being abdominal pain (13 vs 1) and diarrhea (10 vs 0).
Thus, for the oral iron sulphate treatment, despite using the maximal dose over a long period of treatment, many patients remained with anemia and few had normal Hb levels at end of treatment. It was also poorly tolerated, and the iron that is not absorbed may well expose the intestine to adverse or oxidative effects, according to the researchers.
In contrast, although the prescribed dosing appeared to be suboptimal for IV iron treatment, it was highly effective, well tolerated, and restored iron stores rapidly, Dr. Lindgren said.
The study was supported by Renapharma, Sweden.
[Presentation title: Intravenous Iron Sucrose (Venofer(R)) for Treatment of Anaemia in Patients With Inflammatory Bowel Disease (IBD) - a Randomised, Open, Multicentre Study. Abstract OP-G-183]
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