Efficacy, Safety, and Hematologic Recovery Following Intravenous Ferric Carboxymaltose in Patients with Iron Malabsorption-Related Iron Deficiency Anemia: A Prospective Clinical Study.

Background/

Objectives

Autoimmune gastritis (AIG), celiac disease (CD), and gastric surgery (GS) often cause iron deficiency anemia (IDA) due to iron malabsorption. In this clinical context, IDA treatment is often challenging. The first-line IDA treatment is oral iron supplementation followed by intravenous (IV) iron administration when ineffective or not tolerated. Ferric carboxymaltose (FCM) showed efficacy in various clinical settings. Prospective data evaluating the efficacy of IV FCM in IDA patients secondary to iron malabsorption are scant. The aim of the current study was to assess the tolerability, efficacy, and QoL impact of IV FCM for the treatment of IDA patients with iron malabsorption.

Methods

Study design: single-center, prospective observational study: n = 37 adults with AIG, CD, or GS with IDA receiving IV FCM were consecutively included. Endpoints were (i) safety tolerability, (ii) efficacy on IDA recovery (Hb normalization), and (iii) QoL impact. At baseline (T0) and 12 weeks after treatment (T12), a QoL-SF12 questionnaire was assessed. Complete blood count (CBC) and iron status (ferritin, iron, transferrin, transferrin saturation (TS)) were assessed at T0, 4 weeks (T4), and T12 after treatment.

Results

Of the 37 IDA patients, 19 (51.4%) had AIG, 9 (24.3%) CD, and 9 (24.3%) GS; Based on Ganzoni's formula, 24 (64.9%) patients received a single IV FCM infusion (mean ± SEM dosage of 975 ± 12 mg); 13 (35.1%) required two IV infusion sessions with a mean ± SEM cumulative dose of 1400 ± 77 mg. One patient (2.7%) experienced mild adverse events without need for treatment interruption or hospitalization. At T0, anemia was moderate in 7 (18.9%) patients and severe in 1 (2.7%). IDA recovery was achieved in 26 (70.3%) patients at T4 and in 29 (78.4%) at T12. At T4, mean ± SEM Hb increased from 10.8 ± 0.2 g/dL to 12.7 ± 0.1 g/dL, ferritin from 28.5 ± 11.2 ng/mL to 188.2 ± 25.7 ng/mL, and TS from 6.7 ± 0.5% to 23.7 ± 1.9% (p < 0.0001). At T12, mean ± SEM Hb further increased to 13.1 ± 0.2 g/dL (p < 0.05 vs. T4), ferritin slightly decreased to 125 ± 26.7 ng/mL, and TS to 22.7 ± 2.8%. At T12, nonsignificant increases in QoL scores relative to baseline were observed.

Conclusions

IV FCM is a safe and effective treatment leading to IDA recovery in nearly 80% of patients at T12. Thus, when oral iron treatment is not feasible or has failed, IV FCM treatment might be considered a first-line therapeutic option for IDA consequent to iron malabsorption.